Stax Omega4 compared to
Omega1/Omega2/Omega3
February 2024
Amidst the thousands of conventional stereo
recordings that I sampled over the past 15 months
via the new Omega4, I discovered to my surprise
that many hundreds were closet binaural recordings.
By Omega4, I am referring to the SR-X9000. Stax
have given various names, but I have always thought
of their rectangular models as Lambdas, and their
circular flagship models as Omegas:-
Omega1.....SR-Omega.....1993.....90mmφ
Omega2.....SR-007...........1998.....78mmφ
Omega3.....SR-009...........2011.....78mmφ
Omega4.....SR-X9000........2022.....90mmφ
Much has changed in the headphone scene in the
past 20 years. Many exciting new headphones have
appeared – many planar magnetic models, a ribbon
model even, as well as some electrostatic offerings
that vie for a share of the niche market dominated
by Stax.
I have not posted at Head-fi for over 20 years. I share
this essay regarding the four Omegas, with particular
focus on the Omega4. My writeup in 2003 regarding
Omega1 vs Omega2 can be found here.
This essay is long, and it is unlikely that you can finish
in one sitting. It is divided into four sections:-
• SECTION 1: GETTING TO GRIPS WITH THE OMEGA4
• SECTION 2: OMEGA4'S SONIC CHARACTER
• SECTION 3: COMPARISON OF OMEGAS 1,2,3,4
• SECTION 4: FOOTNOTES
______________________________________________________
SECTION 1
GETTING TO GRIPS WITH THE OMEGA4
______________________________________________________
Within just the first few weeks the Omega4 captivated
me with the following:
- the most see-through of the four Omegas
- exquisitely relaxed yet exquisitely clear
- resembles Omega 1 in spatial presentation
- harmonically far richer than the other three
And yet, there was something else I could not quite
put my finger on. The Omega4 had this knack of
sometimes presenting out-of-the-head imagery.
The albums I played were mainly non-binaural, so I
wasn’t expecting to hear out-of-the-head imagery.
Out-of-head imagery may seem cause for celebration.
Yet, there was a problem: the connection between
out-of-head images and in-head images seemed
unclear. In-head images were positioned precisely
around my head, but out-of-head images seemed
hazy and disconnected from in-head imagery.
EUREKA MOMENT
It was only on Month 8 that I chanced upon an approach
that made all the pieces fall into place.
I realised I was sitting in my listening space wrongly. I
usually sat on the sofa next to my audio tower whenever
I listened to headphones. Seemed harmless enough.
At other times I would sit on a low stool and faced my
audio tower, inspecting the display screens of my audio
components. Again, seemed harmless.
PICTURE 1: LISTENING POSTURES ADOPTED DURING FIRST 8 MONTHS
On Month 8, inspiration struck – I planted myself along
the room’s centre axis and faced the opposite wall,
almost as if I was listening to a pair of loudspeakers.
That position was not the most intuitive for a headphone
listener – why adopt a listening posture that seemed
as if a pair of loudspeakers existed in the room, when
none actually did?
PICTURE 2: EUREKA MOMENT – SEEING IMAGES IN 3D SPACE
The new listening posture yielded a paradigm shift for
me. I could now “see” the sonic images in 3D space in
front of me. On Month 8, I “got” the Omega4.
VIRAS-FREE LISTENING POSTURE
I have a tongue-in-cheek acronym for this: VIRAS or
Visually-Induced Rejection of Auditory Staging. When
my eyes focused on nearfield objects, my ears’ ability to
perceive the distances of out-of-head sonic images
became impaired.
My eyes thwarted my ears. I was hit by VIRAS.
Example: if I held a tablet 18 inches in front of me (to
navigate through streamed music), and simultaneously
my headphone portrayed an image 5 feet in front of me,
the visual data that said “18 inches” superseded the
auditory data that said “5 feet”. Due to VIRAS, my brain
did not notice that lovely, lovely, holographic image
hovering 5 feet in front of me. I did notice some sort of
"mist" floating in front of my face, but I did not know
that this distance-indeterminate mist was in fact a proper
sonic image located very precisely 5 feet in front of me.
Here’s another curious thing: in-head sonic images
were immune to visual impairment. Whether I focused
my eyes near or far, the position of the percussive shaker
1 inch outside my forehead remained robust and stable.
Out-of-head images, however, were highly susceptible
to being contradicted visually.
Consequently, to properly perceive the staging nuances
that the Omega4 was capable of, it became necessary for
me to remove all items such as PC screen, newspaper,
book, display screens of audio components, tablet, CD
album covers, handphone, etc from my cone of vision,
whilst listening to the Omega4.
I simply planted myself along the room’s centre axis
and, as the music started, looked straight ahead at the
opposite wall. As the music progressed, my eyes would
flit to the left, to the right, to the centre, etc. My eyes
went to the points in 3D space where the holographic
images were located, as these images flickered in and
out, in tandem with the pulsations and flow of the music.
Once I had adopted a VIRAS-free listening hygiene, all
images – in-head and out-of-head – belonged to one
common spatial container, one coherent recorded venue.
All performers, near or far, in-head or out-of-head,
breathed the same air.
Strangely, closing my eyes or plunging my listening room
into absolute darkness did not work. It was as if darkness
itself presented an impenetrable barrier that blocked
my distance estimation of sonic images.
_______________________________________________
SECTION 2
THE OMEGA4'S SONIC CHARACTER
_______________________________________________
After that eureka moment I began taking confident
notes regarding the Omega4’s sonic character.
Here are my observations:
Observation #1
Omega4’s staging can be divided into zones
Back in 2003 when I compared Omega1 to Omega2,
I reached for the term “headstage” to describe what
I heard via the Omega2. The term denoted the head-
hugging soundfield that the Omega2 portrayed.
The Omega2 has a straight headstage. I use Omega2
as a springboard, since it was the Omega2 that first
made me feel the necessity to coin the term “headstage”.
To be clear, all headphones, not just the Omega2, portray
a headstage.
What I noticed distinctly was: the Omega4’s headstage
was curved, not straight. In the curved headstage, a
center vocal image would be located slightly in front
of the forehead, thereby creating a soundfield with a
distinctly curved arc.
PICTURE 3: THE STRAIGHT AND CURVED HEADSTAGES
But some recordings took things one step further. That
curved soundfield could be detached from my head.
From my notes, I found myself frequently thinking the
word “halo” to describe what I heard through the
Omega4.
A halo is that band of ethereal light surrounding an
angel’s head. While centred on the angel’s head, the
halo is not in contact with the head – it floats free of
the head.
Hence a new term: halostage. The term was especially
relevant because the halostage appeared to be the
Omega4’s default home. Centre vocal images tended
to be located in the halostage. Similarly, lead instruments
such as solo cello, solo trumpet or solo flute also tended
to be located in the halostage.
PICTURE 4: CARTOGRAPHY OF HEADPHONE STAGING
However, the Omega4’s soundfield did not stop at the
halostage. I had to further extend this cartography to
include yet another zone called the “freestage”.
The freestage is further out than the halostage.
The word “free” in “freestage” seemed appropriate,
given that the images within the freestage are entirely
free from the gravitational tug of the headstage.
Freestage images are magical to behold, because they
are externalised, self-illuminated and can even appear
self-motivated.
Approximate sizes of these zones: the curved headstage
encompasses the forehead and a few inches beyond.
The halostage starts from, say, 6 inches in front of the
forehead and ends, say, 18 inches in front of the forehead.
The freestage starts 1½ feet from the forehead and
extends to 8 feet or beyond. Because the freestage was
so deep, I further differentiated the freestage into proximal
freestage, mid freestage and distal freestage.
I emphasise that these diagrams were not drawn based
on what my ears heard – it was not a case of “Image B
sounds further than Image A.” Rather, it was a case of
“I see Image A hover in front of Image B”. The diagrams
here are based on what my eyes judged as distance,
not what my ears heard as depth.
Examples of headstage, halostage and freestage will be
helpful. I own many versions of the Star Wars soundtrack,
collected over decades.
Below are 3 versions of the Throne Room Finale from the
Star Wars soundtrack: a headstage example, a halostage
example and a freestage example.
PICTURE 5: EXAMPLES FROM STAR WARS SOUNDTRACK COLLECTION
The 1st example is the original 1977 version, a historically
significant recording, what with this soundtrack holding
the no.1 pride of place in the American Film Institute’s list
of best soundtracks of all time. To clearly capture the brash,
heroic textures of the orchestra, microphones were placed
close to each instrumental section. Such a microphone
arrangement caused the images to all huddle in a curved
headstage.
The 2nd example, played by Slovak National Symphony
conducted by Robert Ziegler (Sony, 2019), adopted an
audibly different microphone arrangement. The images
were more out-of-the-head, ie, located in the halostage.
I “see” the images floating a foot or two in front of me.
The 3rd example is the most exhilarating version, played
by Los Angeles Philharmonic conducted by Gustavo Dudamel
(Deutsche Grammophon, 2019). All images took place in
the freestage. The nearest instruments were located 3 feet
away, while the furthest instruments were located 10 feet
away. The whole soundstage was narrow but deep. There
was a clear sense of layering: the timpani, bassoons and
horns were way back in the distal freestage, whilst the
trumpets and violins were mid freestage. This was the best
audiophile version of the soundtrack I have encountered.
Observation #2
The Omega4’s staging has its own geometry
I continued to listen to hundreds of recordings, eagerly
tagging my Roon music library into headstage, halostage
and freestage categories. Over time, I began to notice
that the Omega4’s staging had a geometric character.
PICTURE 6: CARTOGRAPHY SPECIFIC TO OMEGA4
There were 5 main slices. The middle slice (Centre Freestage)
had the deepest depth. The other 2 adjacent slices (Left and
Right) had depth that went from Proximal to Distal. The final
2 slices (Far Left and Far Right) were the most curious - their
front portions were cut off.
Below are examples of the spread of images across these
5 pie slices. I emphasise again that this was not what my
ears heard but what my eyes "saw":
PICTURE 7: EXAMPLES
The 1st example is from The Lord of the Rings original
soundtracks, played by London Philharmonic Orchestra;
composed and conducted by Howard Shore. This was a
haunting, fantastical, yet peasant-like, grounded, sweet
music, befitting a mythology that spans thousands of
years of narrative depth. Choral passages weaved and
in and out of orchestral leitmotifs, sung in the fictional
languages of the lore. The deepest instruments and
voices extended into the deep distal freestage. It was as
if depth was not meant to be measured in distance, but
in thousands of years.
The 2nd example is a trumpet piece that had my jaw drop
after the first few trumpet notes. Here was a heightened
sense of airiness – the whole recorded venue completely
lit up on account of just a single instrument. This recording
was the sort that made my heart race, and the sort that
the Omega4 depicted with aplomb. I reiterate: this was
not what my ears heard, but what my eyes "saw".
Now on to an explanation why the Far Right and Far Left
had their front portions cut off by the "genie zone". I will
use Beethoven symphonies as example.
I own roughly 11 sets of the complete Beethoven cycle
(ie 1 to 9), plus loose pieces (ie separate symphonies).
They come in all staging types – headstage, halostage
and freestage. There’s a peculiar phenomenon that occurs
only with the freestage versions of these recordings.
PICTURE 8: THE GENIE TRAP
European orchestras tend to position their string sections
from highest pitch to lowest pitch, in a left-to-right
sequence. The extreme left is 1st violin section, then
2nd violins, then violas, finally cellos, with double basses
seated behind cellos.
This periodically creates a “genie trap” problem over the
Omega4s. The cellos and/or double basses seated at
extreme right can sometimes be positioned too near a
microphone, and consequently get sucked into the
right earcup of the Omega4.
I call this the “genie trap” because this phenomenon
reminds me of a genie getting sucked back into the magic
lamp, against the genie's wishes. The rest of the orchestra
would be out in the freestage, but the poor celloists and
double bassists were marooned in my headstage, right-side.
Recordings of American orchestras tend to not present
this problem, though. American orchestras tend to have
cellos and double basses sit in the centre.
Sonically the best Beethoven cycle I’ve found is a
Reference Recording production, played by Pittsburgh
Symphony Orchestra, conducted by Manfred Honeck.
Images in this recording typically occupied the proximal
freestage and mid freestage, with an occasional image
in the deep freestage. Cellos and double basses were
positioned in the centre.
Locating the lowest notes in the centre of the soundstage
enlists both left and right transducers to contribute to
bass portrayal, instead of relying only on the right-side
transducer to huff and puff the low notes. In the Honeck
version of the Beethoven cycle, the deep growl of bowed
double basses moved and swung left-to-right-and-back
like a giant pendulum across the width of the mid freestage.
I found these to be the best audiophile versions of
Beethoven symphonies.
Observation #3
The Omega4’s staging also encompasses height
The Omega4's spatial portrayal extended in the height
direction as well. Below was how this rendition of My Girl
played out spatially:
PICTURE 9: A Distortion Of Love (Patricia Barber)
Polygram Records, 1991
Vocal images typically hover in front of my face, at the
same horizontal level. But here, Patricia Barber’s voice
hovered high up – eyeballs looking up was insufficient –
my neck had to crank up to enable me to “see” her voice.
Each time I looked up, I half expected to see the underside
of Patricia Barber’s chin. As irony would have it, my chin,
too, became involved in the proceedings – the plucking
of the double bass occurred right below my chin. The
plucked double bass was full-bodied yet airy; my jawline
felt like it was given a massage.
It wasn’t often that I came across such dramatized height
portrayals, with a vocal image so high up yet so close to
me, so much so that my neck had to crank. Most of the
time, it would be a wall of massed violins or massed brass
instruments that scaled the crowning point of a soundstage.
But usually, those walls of massed violins or massed brass
would be located some comfortable distance away from
me, mercifully saving me from any neck-cranking.
Observation #4
Staging Variability is a marker for transparency
Over months of listening, I concluded that the Omega4
had a chameleon-like staging. Below is a small sampling
of the many, many, varied presentations I encountered.
Every time I started playing a new unfamiliar album, I wasn’t
sure what I would be getting. The first few seconds would
be filled with fresh anticipation.
PICTURE 10: HEADPHONE STAGING VARIABILITY
Headphone Staging Variability (HSV) refers to the range
of possible staging types that a headphone can portray. A
headphone with a high HSV is chameleon-like in its staging.
Diagram above shows the HSV of the Omega4. The orange
vertical band shows all possible zones you might find a
sonic image via the Omega4. The Omega4’s full range of
variability goes from straight headstage all the way to
distal freestage, with its default home being the halostage.
HSV is a marker for transparency – a highly accurate
headphone will have a high HSV. I suspect that with HSV,
it is possible to compare headphones without having
them side-by-side. If Headphone A portrays all sorts of
staging shapes and sizes (recording-dependent), and
Headphone B is more limited in its variability across
recordings, then Headphone A is the more transparent
one.
_______________________________________________
SECTION 3
COMPARISON OF OMEGAS 1,2,3,4
_______________________________________________
I now feel ready to compare the Omega4 to the three
earlier siblings. Without an adequate framework to cope
with the Omega4, it would be difficult to compare the
Omega4 with its siblings. But now I have an adequate
framework.
I own all four models. However, I do not own nor have I
heard the secondary off-shoots, eg the Mk2 version of
Omega2 and the Mk2 version of Omega3.
All four of my Omegas are in good working order, inc
my 31-year old Omega1. (Whenever unused, they were
kept in a humidity-controlled, temperature-stable, dust-
free, UV-free storage solution all these years.)
Although I was familiar with the sound of the three
Omegas, I needed all four of them to play by the same
playbook. Hence I re-listened to all three earlier Omegas
with my upgraded system as well as with a VIRAS-free
protocol.
THE FOUR OMEGAS –
HISTORICAL CONTINUITIES AND DISCONTINUITIES
I referred to the four models as “Omegas” as if there was
an unbroken historical continuity from one to the next.
The reality is: the historical passage of the four models
is characterised by continuities as well as discontinuities.
PICTURE 11: MODEL NAMING, DIAPHRAGM DIAMETER, WEIGHT
Model naming seems to be marked by discontinuity.
The first model had only a Greek alphabet (“Omega”)
for its name. The next two models formed a continuity
(007 then 009), but this continuity was interrupted by
the 4th model (X9000). To be sure, there is nothing
unusual about manufacturers ending a name line and
starting a new one.
More interesting is the diaphragm diameter: one might
expect a continuity - Omega1 with the smallest diameter,
then Omega2 slightly larger diameter, and so on. But
that's not what happened. Omega1 and Omega4 have
large diaphragms (90mm diameter), while Omega2 and
Omega3 have smaller diaphragms (78mm diameter).
Stax’s promotion pamphlet for the Omega4 does mention
that the Omega4 was a conscious return to the large
90mm diameter roots.
The diameter was reduced from 90mm to 78mm when
Stax found that the process of hand-assembling the
large-diameter Omega1 eventually proved untenable as
a production protocol. Omega1 was discontinued after
only 5 years, replaced by the small diameter Omega2
in 1998. Omega3 continued the 78mm approach.
When Stax solved the challenges related to production
of large diaphragms, the Omega4 arrived. Omega 1 and
Omega4 are both eager to portray images in the halostage
and freestage. I speculate that the large diaphragm of
Omega1 and Omega4 is cause for their staging prowess.
STAGING OF THE FOUR OMEGAS
PICTURE 12: staging of the four Omegas
So how did the four Omegas compare, when playing
distance-miked recordings? I must admit to being VERY
surprised that the Omega2 and Omega3 were capable
of out-of-the-head imagery! My memory of them was
that they were headstagey headphones (especially
Omega2).
But once I played them through my upgraded system
and in a VIRAS-free manner, they showed me that they
too were capable of out-of-the-head imagery, albeit in
a reduced manner compared to Omega1 and Omega4.
Omega1 more clearly portrayed the Sense of Venue out in
the freestage than Omega2 and Omega3. But the Omega4
was capable of not just locating ambience out in the
freestage, but it also portrayed Textural Cores and Bodies
out in the freestage more palpably.
When it comes to close-miked recordings, Omega 2 and
Omega 3 tended to portray straight headstages and
curved headstages, while the Omega 1 and Omega 4
tended to portray curved headstages and halostages.
HSV OF THE FOUR OMEGAS
PICTURE 13: Staging Variability of the four Omegas
Omega1 and Omega4 have the widest variability of
staging, from recording to recording. With these two
models, the Sense of Venue could change drastically
from recording to recording. If the recording contained
strong ambience cues, Omega1 and Omega4 allowed
me to “see” the far end of recorded venue located some
say 8 feet from me (distal freestage).
The Omega3 presented less variability than Omega1 and
Omega4. The Omega2 displayed the least variability of
the four models.
RELAXED CLARITY & BACKGROUND BLACKNESS
PICTURE 14: relaxed clarity and background blackness
Relaxed clarity is high up there for me as a strength for
a headphone to have. Of the four, Omega1 was the least
relaxed, because its background between upper-mid notes
was not as black as the other three Omegas. I found the
Omega2 to be a improvement over the Omega1 in this
aspect of background blackness and hence relaxed clarity.
I did find the Omega3 to be slightly less relaxed than the
Omega2, if only because the Omega3 was more upfront,
less laidback in its presentation style. Among the four,
the Omega4 is in a class by itself - it has more clarity yet
is also paradoxically more relaxed, than the other three.
I found that there isn’t just one type of background
between notes. Rather, there are 3 types:
Omega4 is audibly superior to Omega1 when it comes
to the background blackness between upper mid notes.
I suspect this is the dividend payoff from the Omega4’s
slanted protection mesh, which Stax says reduces
reflections from the mesh back into the listener’s ears.
With the Omega1, the background between upper mid
notes is not as black as the Omega4’s. I speculate that
reflections from the protection mesh is involved in
reducing the sense of background blackness in the
upper-mids and highs. Perhaps a resourceful modder
might one day come up with a DIY'ed Omega1 with
angled protection mesh (!)
TONAL BALANCE & HARMONIC RICHNESS
I would describe Omega1 and Omega4 as being tonally
neutral, while Omega2 is dark and Omega3 slightly bright.
Omega2 is darker than Omega3 is bright. But a description
of the overall tonal balance is insufficient to explain
another aspect where the Omega4 stands heads and
shoulders above all three: harmonic richness.
Harmonic richness is where a pianist hits, say, the
middle-C key, and a rich pallete of undertones and
overtones accompany the primary note.
PICTURE 15: tonal balance and harmonic richness
The Omega1 is a rich midrangey headphone: the middle-C
comes off pure. Omega2 thickens the undertones quite
substantially. Omega3 has a very slight treble lift to the
overtones.
But it is the Omega4 that trounces all three siblings –
there is a so much richness to the undertones and
overtones. If I listened to each headphone separately,
I might not have noticed this. But quick-swopping
between them made the Omega4’s incredible harmonic
richness obvious. Omega1 is neutral, but Omega4 is
neutral with much richer lower and upper harmonics.
FOUR SONIC PARADIGMS
PICTURE 16: four sonic paradigms
I tend to see any headphone as belonging to one of four
possible paradigms. I see the Omega1 and Omega4
belonging to the Spatial paradigm.
I see the Omega2 belonging to the Lyrical paradigm. The
Lyrical paradigm is a paradigm that values smoothness,
mellifluousness; such a headphone carries the lilt and
tunefulness of music.
I see the Omega3 as somewhat belonging to the Detail
paradigm. In this paradigm, details are brought upfront
to the listener’s attention. Strangely, although I categorise
the Omega3 under the Detail paradigm, it is actually
not as detailed as the Omega4. The Omega4, although
more detailed, does not push the details to your face.
The Omega3, on the other hand, does give an impression
of serving details upfront to the listener’s attention.
I don’t see any of the four Omegas belonging to the
Rhythmic paradigm, which values physicality and slam.
WHERE IS STAX GOING FROM HERE?
PICTURE 17: release timeline of Omegas
Stax seems to introduce a new flagship model at the
start of each new decade. (The outlier is the Omega2,
a case of emergency premature birth.)
Should we expect a new flagship in the early-2030s? Will it
be an Omega of 90mm diameter? Maybe larger diameter?
(If 90 is better than 78, wouldn’t 102 be better than 90?)
Or maybe the next flagship is not even an Omega, but
an outsized Lambda? Or something totally new?
My hope is that at the very least, Stax takes the large
diameter throughline from Omega1 to Omega4 and
continues from there, rather than from the 78mm diameter
throughline from Omega2 to Omega3. But it is really not
up to me or to any of us - each manufacturer has to
compete in the marketplace and make their own strategic
decisions.
SUMMARY FOR OMEGA4
The Omega4 is a groundbreaking headphone in a deep
personal sense. I already have 45 years of immersion in
this headphone hobby. By all accounts I should not be
this excited about a new headphone on my 45th year in
the hobby.
The Omega4 began as an affront to what I thought I knew
(“all headphones are necessarily headstagey”) and ended
as a headphone that changed my understanding of how
sound works. It made me adopt/formulate new conceptual
frameworks to deepen my enjoyment of the hobby.
SUMMARY (FOR ALL HEADPHONES GENERALLY)
I highly suspect that all headphones portray images in
the halostage and freestage if we only gave them the
chance to do so. I base my suspicion on 3 things:-
i. my Omega2, which I thought of as being headstagey,
suddenly could portray out-of-head images, once I gave
it a chance
ii. I notice Youtubers sharing similar observations too.
Sajid Amit mentions the Abyss 1266 Phi TC and the Raal
SR1a as both being able to project out-of-the-head.
ConvinceMeAudio often points his finger mid-air to
describe specific sonic images floating in space.
iii. I once demo'ed console gaming headphones -
sure enough the roaring monster and shrieking damsel
were "out there". And this was just a $100+ headphone,
hardly high-end.
So yes, I think all headphones can project out-of-the-head.
You only need two ingredients:-
i. distance-miked recordings
ii. orient your head/body formally in your listening space
and look straight at the opposite wall.
Footnote 6 contains a series of tracks that you can play
over your headphones at home, to hear (and see) for
yourself.
____________________________________________________
SECTION 4
FOOTNOTES
____________________________________________________
This section is more technical; it goes into the whys and
hows of things. I did not want such technical explanations
to interrupt the flow of the main essay, which was why
I extracted the technical bits and placed them into this
Detailed Footnotes section. It was a thrilling adventure
for me to understand how a headphone projects out-of-
the-head images, such that I can "see" images in front
of me.
____________________________________________________
Footnote 1
HOW ARE HEADPHONES ABLE TO PROJECT
OUT-OF-THE-HEAD IMAGES ?
Sonic depth is analogous to visual depth, so I will use visual
metaphors to explain:
PICTURE 18: mono versus stereo vision
In stereo depth, left and right eye see two different versions
of the world. Your eye/brain interface brings the two disparate
images together, and you see real three dimensional depth.
In mono depth, left eye and right eye see the same thing.
Same with our ears. The left ear and the right ear hear
two slightly different versions of the world:
PICTURE 19: stereo hearing arises from ILD, ITD and HRTF
The frequency balance difference arises because sound
has to negotiate around facial features (nose, cheeks,
forehead) to get to the ear on other side of your face.
As the sound travels to your other ear, your face changes
the tonal balance of that sound. Your brain then looks at
the tonal balance of the right ear and the left ear, and
computes the difference. This difference then allows your
brain to estimate the position of the sound source. Your
ear/brain interface takes all three data sets (ILD, ITD and
HRTF) and establishes the 3D distance of the source.
A pair of microphones mimics your pair of ears:
PICTURE 20: distance-miked recordings
In the diagram above, a pair of microphones records
the sonic world. Left microphone captures a set of levels
and arrival times; right microphone captures a slightly
different set of levels and arrival times. ILD and ITD are
both captured.
A headphone is an inverse-microphone. The left
headphone plays what the left microphone captured,
while the right headphone plays what the right microphone
captured. The headphone recreates the recorded venue.
The distance between microphones and performers
becomes perceived as distance between the headphone-
listener and the sonic images hovering in the freestage.
For orchestral music where distances are large between
microphone and performers, the wavefront approximates
that of a source located at infinity. The two paths are
almost parallel, so sound does not have to negotiate
around facial features to get to one ear or the other.
For such faraway sources, HRTF becomes less relevant.
PICTURE 21: faraway sound sources relative to head
This was why I experienced “binaural sound” so often
via the Omega4s while playing normal non-binaural
distance-miked recordings. In the opening paragraph of
this essay, I called them "closet binaural recordings".
In truth, they were recordings that contained ILD and
ITD information, which was sufficient to create images
that I could "see" hovering in the halostage and freestage.
Binaural recordings contain ILD, ITD and HRTF information,
but the HRTF component is not crucial when it comes
to distance-miked recordings of faraway sources.
PICTURE 22: close-miked recording of an orchestra
Now on to close-miked recordings. Picture above shows
an orchestra recorded with multiple microphones, each
positioned close to instruments. In effect, each instrument
section is recorded with a single mono microphone.
Being mono, ILD and ITD are not captured. The whole
orchestra is recorded by an army of mono microphones.
Each mono signal is then brought together at the mixing
console, where an engineer assigns the position of each
instrument along a left-to-right continuum. He/she is
unable to assign position along the front-to-back axis,
because ILD and ITD information is missing.
The resulting presentation will be headstagey over
headphones. Each sonic image, being devoid of ILD and
ITD information, will unavoidably be cocooned inside
the headstage.
____________________________________________________
Footnote 2
OMEGA4 IS NOT SPEAKER-LIKE;
IT IS AN INVERSE-MICROPHONE
This observation is the most nuanced insight of this essay.
The Omega4 was not trying to be “speaker-like”; it was
simply being an inverse-microphone.
Being speaker-like would mean that the soundfield was
detached from me and "came at me" from the front. But
this was not what happened with the Omega4.
Rather, the Omega4 was immersing me in the soundfield
of the recorded event. Diagram below clarifies:
PICTURE 23: immersion of the headphone-listener in the soundfield
Diagram A shows a trumpet plus venue reflections. The
microphones pick up the direct sound of the trumpet, and
also the reflections from the recorded venue.
Diagram B shows the inverse condition during playback.
The headphone-listener hears the recreation of the recorded
event. He hears the reflections coming at him from all angles
(the reflected soundfield). The soundfield is not detached
from the headphone. He is immersed in the soundfield.
Diagram C graphically simplifies what's going on. The
trumpet sound is shown in 3 shades of orange:
- Textural Core (the sharp textures of the instrument)
- Body (the main body of the sound of the instrument)
- Sense of Venue (airiness, ambience)
Only Textural Core and Body can ever be hoped to be
free of the head. The 3rd component (Sense of Venue)
will always be tethered to the headphone listener’s head.
With headphones, there will always be a sense of immersion
in the recorded event.
An insistence that the headphone does not have any
soundfield around the head is effectively an insistence
that the soundfield does not reach the microphones.
(But if the soundfield did not reach the microphones,
how was the musical event ever be recorded?)
Hence all the diagrams in this essay that show out-of-
head images in the halostage and freestage must be
read with the understanding that the 3rd component
(Sense of Venue) remains a head-immersing soundfield.
The headphone listener will always experience his/her
head being immersed in a soundfield, no matter that
Textural Cores and Bodies are out there in the freestage.
The experience of listening to acoustic recordings via
high end headphones is thus fundamentally different
from that via loudspeakers.
The Omega4 is steadfastly not speaker-like. It is simply
an inverse-microphone, albeit a highly transparent one.
____________________________________________________
Footnote 3
BINAURAL versus NON-BINAURAL RECORDINGS
I did not find binaural recordings to have any special
stranglehold on out-of-the-head imagery. Many non-
binaural recordings gave me out-of-head imagery via
the Omega4.
I was able to put this to the test. I own both the binaural
and non-binaural versions of Chasing The Dragon’s
production of Bizet’s Carmen Habanera.
The Habanera piece was sung by Rosie Middleton,
accompanied by the National Symphony Orchestra,
conducted by Debbie Wiseman.
It wasn’t as if they recorded the performance in stereo
one day, and in binaural another day. Here was a rare
example of a performance captured simultaneously by
binaural and non-binaural microphones. The binaural
microphone and the stereo microphone were both
placed at the same distance from the performers.
PICTURE 24: non-binaural versus binaural recording
Both recordings yielded out-of-the-head imagery via
the Omega4. In fact, they sounded close, and I needed
to do A-B swops to discern the differences.
Key observations:-
Firstly, the binaural version had Bodies with more volume
and size.
Secondly, the cellos at the right side genie zone did get
sucked into the right earcup; I was hoping binaural
recordings could avoid the genie trap. It does appear
to me that irrespective of whether the microphone is
binaural or stereo, the microphones closest to the
musicians seated at extreme left or right have to be
carefully positioned to avoid the genie trap.
Thirdly, the non-binaural version had deeper freestage
depth. The binaural version had wider freestage width.
My broader observation has been: in non-binaural
recordings, perspective recedes in a more accelerated
way (photography buffs might know that wide-angle
lenses also present accelerated perspective). Binaural
recordings do not seem to present such dramatized
perspectives.
Lastly, both versions had the plucked violins located
just outside the left earcup. Bowed violins sounded
further away, whilst plucked violins were located much
nearer. The same instrument could be “seen” to be
further or nearer depending on how it was played!
This was consistent with some other albums I played:
in a Lord of the Rings cover version, in the scene where
he was newly crowned, Aragorn sings an Elvish poem.
Because the recitation was sung slowly, it was easy for
me to differentiate the Elvish vowels and consonants.
I noticed that when a vowel was sung, the vocal image
was located 4 feet from me, and when a consonant was
sung, the vocal image moved 1 foot closer to me, then
back again when the next vowel was sung. It appeared
to me that texturally-sharp sounds (such as consonants)
moved closer to the headphone listener.
____________________________________________________
Footnote 4
CROSSFEED ON DISTANCE-MIKED RECORDINGS
The Omega4 gave me confidence to make observations
about various aspects of staging over headphones. One
of the things I was very curious to try was crossfeed,
having not tried it before.
Roon has a DSP-based crossfeed facility, which I excitedly
experimented with.
I found crossfeed to drastically reduce perception of 3D
depth. Once Roon’s crossfeed DSP was switched on, I
found the sense of airiness and 3D imaging collapsed.
The reason is: stereo-aural depth (of distance-miked
recordings) requires the right and left channels to carry
completely different signals. There are level differences (ILD)
and timing differences (ITD) between left and right channels.
Stereo-aural depth works if the left headphone plays what
the left microphone picked up, and the right headphone
plays what the right microphone picked up.
Bleeding a small percentage of one channel into the other
blends the level difference between left and right (ILD),
but completely garbles the timing difference (ITD).
Timing-wise, the sound of an instrument reaches say the
left microphone either at Moment X or Moment Y, rather
than a blended moment of X and Y. A blended moment
(time smear) runs contrary to how the brain prefers things
to work.
____________________________________________________
Footnote 5
MULTI-MIKED RECORDINGS (POP, ROCK, EDM, etc)
It is easy to mistake close-miked recordings (pop, rock,
rap, EDM, etc) to be stereo recordings. In truth, these
weren’t recorded in a genuine stereo manner.
Stereo does not mean left-to-right distribution; stereo
means depth information is encoded as level difference
and arrival time difference between left and right channels.
Close-miked recordings in fact involve an army of mono
microphones. Typically, one mono-microphone is deployed
per voice or instrument. The recording engineer then
distributes the disparate mono signals across a left-to-right
continuum. He/she also modifies each mono signal using
an array of tools, eg reverb specifics, tonal adjustments.
The recording engineer, through a series of creative
decisions, constructs the fictional soundstage. I do not use
the word "fictional" in a derogative way. I use "fictional"
in the sense that creative agency is involved in crafting
something that did not exist beforehand.
Because each mono-mike is placed near each performer,
the resulting images of the performers will unavoidably
be located in the headstage. When you are listening to
a “stereo” pop recording you are in effect listening to a
series of mono images distributed across the left-to-right
real estate of the headstage. The soundfield is head-
hugging because the recording is essentially mono. (The
moment the recording is genuinely stereo, the images
move out of the headstage and into the halostage and
freestage.)
Music that inhabits the halostage and freestage is not
superior to music that inhabits the headstage. Distance-
miked music is not superior to close-miked music. Many
expressive forms of music require performers to get
close to the microphones to capture the inflections,
expressions or emotional intensity that are intrinsic to
their music-making. Think of the many, many, history-
making recordings – many were close-miked recordings.
This essay focuses on distance-miked music as a sonic
starting point that causes headphones to create out-of-
head images. The essay is not saying that close-miked
music is inferior, which is plainly untrue.
____________________________________________________
Footnote 6
TEST TRACKS TO TRY AT HOME
These are for you to try over your headphones at home.
Search your streaming platform for these keywords.
Play the Headstage version first, then the Freestage version.
The contrast, the sudden opening up, the sudden leaping
forward of the images from headstage to freestage, will
be dramatic.
MAY IT BE (cover versions of Enya's haunting song)
Headstage version: Harley Westenra
Freestage version: Boston Symphonic Orchestra
CARMINA BURANA (opera, Carl Orff)
Headstage version: Niklaus Aeschbacher
Freestage version: Saint Louis Symphony Orchestra
ALA TURCA (piano, Mozart)
Headstage version: Friedrich Gulda
Freestage version: Kristain Bezuidenhout
MADAME BUTTERFLY (opera, Puccini)
Headstage version: Victoria de los Angeles
Freestage version: Teatro Reale dell'Opera di Roma
FLIGHT OF THE BUMBLEBEE (orchestra, Rimsky-Korsakov)
Headstage version: Erick Friedman, Brooks Smith
Freestage version: Sinfonia Lahti Cello
____________________________________________________
Footnote 7
MY SETUP
Source components are the Grimm MU-1 streamer and
Mola Mola Tambaqui digital analog converter. The MU-1
connects to the Tambaqui via Furutech’s flagship aes/ebu
cable. The Tambaqui connects to the Stax SRM-T2 via
Audioquest’s flagship interconnects. All components
(including the T2) get power from Audioquest’s smallest
power conditioner (Niagara 1200).
Only the MU-1 is connected via ethernet to the router;
the Tambaqui is not. This ensures that the MU-1's output
indeed goes out via its FPGA resampling facility. (In the
"Identify" settings of Roon, Grimm was not one of the
available options. I identified the Grimm as a Mola Mola
product - only by doing so could I get the Grimm to
circumvent Roon and hence send its output via aes/ebu.
If you own a MU-1, make sure your DAC is not connected
via ethernet to a router.)
The sonic improvements brought about by the MU-1/
Tambaqui have been very satisfying – more relaxed,
more spacious, more precise positioning of Textural
Cores and Bodies. In fact, inserting the MU-1 has been
revelatory; it convinced me that achieving zero-jitter
does mean that time coherence is better preserved
(hence ITD information is more accurately portrayed –
leading to more accurate imaging in the halostage and
freestage).
Each component sits on a set of 4 magnetic levitation
feet. Each foot has a 10kg load capacity. I used to have
an audio rack with fussy little springs and ballbearings.
I got rid of that rack and opted instead for magnetic
levitation instead. I did not hear any sound deterioration,
plus I preferred the naked look of one component sitting
(floating) on another component below.
For 30 years my system had always revolved around the
Stax SRM-T2 amp. I have upgraded my DAC four times
over this period. I have changed my headphones from
Omega1 to Omega2 to Omega3 to Omega4. But the
T2 has remained a constant.
This has resulted in me remaining within the Stax
headphone ecosystem for 30 years. I have only ever
bought a new headphone once every decade. Apologies
for being unable to furnish any insights into other
headphones.
Cheers and happy listening, everyone.
__________________________________________________________
Omega1/Omega2/Omega3
February 2024
Amidst the thousands of conventional stereo
recordings that I sampled over the past 15 months
via the new Omega4, I discovered to my surprise
that many hundreds were closet binaural recordings.
By Omega4, I am referring to the SR-X9000. Stax
have given various names, but I have always thought
of their rectangular models as Lambdas, and their
circular flagship models as Omegas:-
Omega1.....SR-Omega.....1993.....90mmφ
Omega2.....SR-007...........1998.....78mmφ
Omega3.....SR-009...........2011.....78mmφ
Omega4.....SR-X9000........2022.....90mmφ
Much has changed in the headphone scene in the
past 20 years. Many exciting new headphones have
appeared – many planar magnetic models, a ribbon
model even, as well as some electrostatic offerings
that vie for a share of the niche market dominated
by Stax.
I have not posted at Head-fi for over 20 years. I share
this essay regarding the four Omegas, with particular
focus on the Omega4. My writeup in 2003 regarding
Omega1 vs Omega2 can be found here.
This essay is long, and it is unlikely that you can finish
in one sitting. It is divided into four sections:-
• SECTION 1: GETTING TO GRIPS WITH THE OMEGA4
• SECTION 2: OMEGA4'S SONIC CHARACTER
• SECTION 3: COMPARISON OF OMEGAS 1,2,3,4
• SECTION 4: FOOTNOTES
______________________________________________________
SECTION 1
GETTING TO GRIPS WITH THE OMEGA4
______________________________________________________
Within just the first few weeks the Omega4 captivated
me with the following:
- the most see-through of the four Omegas
- exquisitely relaxed yet exquisitely clear
- resembles Omega 1 in spatial presentation
- harmonically far richer than the other three
And yet, there was something else I could not quite
put my finger on. The Omega4 had this knack of
sometimes presenting out-of-the-head imagery.
The albums I played were mainly non-binaural, so I
wasn’t expecting to hear out-of-the-head imagery.
Out-of-head imagery may seem cause for celebration.
Yet, there was a problem: the connection between
out-of-head images and in-head images seemed
unclear. In-head images were positioned precisely
around my head, but out-of-head images seemed
hazy and disconnected from in-head imagery.
EUREKA MOMENT
It was only on Month 8 that I chanced upon an approach
that made all the pieces fall into place.
I realised I was sitting in my listening space wrongly. I
usually sat on the sofa next to my audio tower whenever
I listened to headphones. Seemed harmless enough.
At other times I would sit on a low stool and faced my
audio tower, inspecting the display screens of my audio
components. Again, seemed harmless.
PICTURE 1: LISTENING POSTURES ADOPTED DURING FIRST 8 MONTHS
On Month 8, inspiration struck – I planted myself along
the room’s centre axis and faced the opposite wall,
almost as if I was listening to a pair of loudspeakers.
That position was not the most intuitive for a headphone
listener – why adopt a listening posture that seemed
as if a pair of loudspeakers existed in the room, when
none actually did?
PICTURE 2: EUREKA MOMENT – SEEING IMAGES IN 3D SPACE
The new listening posture yielded a paradigm shift for
me. I could now “see” the sonic images in 3D space in
front of me. On Month 8, I “got” the Omega4.
VIRAS-FREE LISTENING POSTURE
I have a tongue-in-cheek acronym for this: VIRAS or
Visually-Induced Rejection of Auditory Staging. When
my eyes focused on nearfield objects, my ears’ ability to
perceive the distances of out-of-head sonic images
became impaired.
My eyes thwarted my ears. I was hit by VIRAS.
Example: if I held a tablet 18 inches in front of me (to
navigate through streamed music), and simultaneously
my headphone portrayed an image 5 feet in front of me,
the visual data that said “18 inches” superseded the
auditory data that said “5 feet”. Due to VIRAS, my brain
did not notice that lovely, lovely, holographic image
hovering 5 feet in front of me. I did notice some sort of
"mist" floating in front of my face, but I did not know
that this distance-indeterminate mist was in fact a proper
sonic image located very precisely 5 feet in front of me.
Here’s another curious thing: in-head sonic images
were immune to visual impairment. Whether I focused
my eyes near or far, the position of the percussive shaker
1 inch outside my forehead remained robust and stable.
Out-of-head images, however, were highly susceptible
to being contradicted visually.
Consequently, to properly perceive the staging nuances
that the Omega4 was capable of, it became necessary for
me to remove all items such as PC screen, newspaper,
book, display screens of audio components, tablet, CD
album covers, handphone, etc from my cone of vision,
whilst listening to the Omega4.
I simply planted myself along the room’s centre axis
and, as the music started, looked straight ahead at the
opposite wall. As the music progressed, my eyes would
flit to the left, to the right, to the centre, etc. My eyes
went to the points in 3D space where the holographic
images were located, as these images flickered in and
out, in tandem with the pulsations and flow of the music.
Once I had adopted a VIRAS-free listening hygiene, all
images – in-head and out-of-head – belonged to one
common spatial container, one coherent recorded venue.
All performers, near or far, in-head or out-of-head,
breathed the same air.
Strangely, closing my eyes or plunging my listening room
into absolute darkness did not work. It was as if darkness
itself presented an impenetrable barrier that blocked
my distance estimation of sonic images.
_______________________________________________
SECTION 2
THE OMEGA4'S SONIC CHARACTER
_______________________________________________
After that eureka moment I began taking confident
notes regarding the Omega4’s sonic character.
Here are my observations:
Observation #1
Omega4’s staging can be divided into zones
Back in 2003 when I compared Omega1 to Omega2,
I reached for the term “headstage” to describe what
I heard via the Omega2. The term denoted the head-
hugging soundfield that the Omega2 portrayed.
The Omega2 has a straight headstage. I use Omega2
as a springboard, since it was the Omega2 that first
made me feel the necessity to coin the term “headstage”.
To be clear, all headphones, not just the Omega2, portray
a headstage.
What I noticed distinctly was: the Omega4’s headstage
was curved, not straight. In the curved headstage, a
center vocal image would be located slightly in front
of the forehead, thereby creating a soundfield with a
distinctly curved arc.
PICTURE 3: THE STRAIGHT AND CURVED HEADSTAGES
But some recordings took things one step further. That
curved soundfield could be detached from my head.
From my notes, I found myself frequently thinking the
word “halo” to describe what I heard through the
Omega4.
A halo is that band of ethereal light surrounding an
angel’s head. While centred on the angel’s head, the
halo is not in contact with the head – it floats free of
the head.
Hence a new term: halostage. The term was especially
relevant because the halostage appeared to be the
Omega4’s default home. Centre vocal images tended
to be located in the halostage. Similarly, lead instruments
such as solo cello, solo trumpet or solo flute also tended
to be located in the halostage.
PICTURE 4: CARTOGRAPHY OF HEADPHONE STAGING
However, the Omega4’s soundfield did not stop at the
halostage. I had to further extend this cartography to
include yet another zone called the “freestage”.
The freestage is further out than the halostage.
The word “free” in “freestage” seemed appropriate,
given that the images within the freestage are entirely
free from the gravitational tug of the headstage.
Freestage images are magical to behold, because they
are externalised, self-illuminated and can even appear
self-motivated.
Approximate sizes of these zones: the curved headstage
encompasses the forehead and a few inches beyond.
The halostage starts from, say, 6 inches in front of the
forehead and ends, say, 18 inches in front of the forehead.
The freestage starts 1½ feet from the forehead and
extends to 8 feet or beyond. Because the freestage was
so deep, I further differentiated the freestage into proximal
freestage, mid freestage and distal freestage.
I emphasise that these diagrams were not drawn based
on what my ears heard – it was not a case of “Image B
sounds further than Image A.” Rather, it was a case of
“I see Image A hover in front of Image B”. The diagrams
here are based on what my eyes judged as distance,
not what my ears heard as depth.
Examples of headstage, halostage and freestage will be
helpful. I own many versions of the Star Wars soundtrack,
collected over decades.
Below are 3 versions of the Throne Room Finale from the
Star Wars soundtrack: a headstage example, a halostage
example and a freestage example.
PICTURE 5: EXAMPLES FROM STAR WARS SOUNDTRACK COLLECTION
The 1st example is the original 1977 version, a historically
significant recording, what with this soundtrack holding
the no.1 pride of place in the American Film Institute’s list
of best soundtracks of all time. To clearly capture the brash,
heroic textures of the orchestra, microphones were placed
close to each instrumental section. Such a microphone
arrangement caused the images to all huddle in a curved
headstage.
The 2nd example, played by Slovak National Symphony
conducted by Robert Ziegler (Sony, 2019), adopted an
audibly different microphone arrangement. The images
were more out-of-the-head, ie, located in the halostage.
I “see” the images floating a foot or two in front of me.
The 3rd example is the most exhilarating version, played
by Los Angeles Philharmonic conducted by Gustavo Dudamel
(Deutsche Grammophon, 2019). All images took place in
the freestage. The nearest instruments were located 3 feet
away, while the furthest instruments were located 10 feet
away. The whole soundstage was narrow but deep. There
was a clear sense of layering: the timpani, bassoons and
horns were way back in the distal freestage, whilst the
trumpets and violins were mid freestage. This was the best
audiophile version of the soundtrack I have encountered.
Observation #2
The Omega4’s staging has its own geometry
I continued to listen to hundreds of recordings, eagerly
tagging my Roon music library into headstage, halostage
and freestage categories. Over time, I began to notice
that the Omega4’s staging had a geometric character.
PICTURE 6: CARTOGRAPHY SPECIFIC TO OMEGA4
There were 5 main slices. The middle slice (Centre Freestage)
had the deepest depth. The other 2 adjacent slices (Left and
Right) had depth that went from Proximal to Distal. The final
2 slices (Far Left and Far Right) were the most curious - their
front portions were cut off.
Below are examples of the spread of images across these
5 pie slices. I emphasise again that this was not what my
ears heard but what my eyes "saw":
PICTURE 7: EXAMPLES
The 1st example is from The Lord of the Rings original
soundtracks, played by London Philharmonic Orchestra;
composed and conducted by Howard Shore. This was a
haunting, fantastical, yet peasant-like, grounded, sweet
music, befitting a mythology that spans thousands of
years of narrative depth. Choral passages weaved and
in and out of orchestral leitmotifs, sung in the fictional
languages of the lore. The deepest instruments and
voices extended into the deep distal freestage. It was as
if depth was not meant to be measured in distance, but
in thousands of years.
The 2nd example is a trumpet piece that had my jaw drop
after the first few trumpet notes. Here was a heightened
sense of airiness – the whole recorded venue completely
lit up on account of just a single instrument. This recording
was the sort that made my heart race, and the sort that
the Omega4 depicted with aplomb. I reiterate: this was
not what my ears heard, but what my eyes "saw".
Now on to an explanation why the Far Right and Far Left
had their front portions cut off by the "genie zone". I will
use Beethoven symphonies as example.
I own roughly 11 sets of the complete Beethoven cycle
(ie 1 to 9), plus loose pieces (ie separate symphonies).
They come in all staging types – headstage, halostage
and freestage. There’s a peculiar phenomenon that occurs
only with the freestage versions of these recordings.
PICTURE 8: THE GENIE TRAP
European orchestras tend to position their string sections
from highest pitch to lowest pitch, in a left-to-right
sequence. The extreme left is 1st violin section, then
2nd violins, then violas, finally cellos, with double basses
seated behind cellos.
This periodically creates a “genie trap” problem over the
Omega4s. The cellos and/or double basses seated at
extreme right can sometimes be positioned too near a
microphone, and consequently get sucked into the
right earcup of the Omega4.
I call this the “genie trap” because this phenomenon
reminds me of a genie getting sucked back into the magic
lamp, against the genie's wishes. The rest of the orchestra
would be out in the freestage, but the poor celloists and
double bassists were marooned in my headstage, right-side.
Recordings of American orchestras tend to not present
this problem, though. American orchestras tend to have
cellos and double basses sit in the centre.
Sonically the best Beethoven cycle I’ve found is a
Reference Recording production, played by Pittsburgh
Symphony Orchestra, conducted by Manfred Honeck.
Images in this recording typically occupied the proximal
freestage and mid freestage, with an occasional image
in the deep freestage. Cellos and double basses were
positioned in the centre.
Locating the lowest notes in the centre of the soundstage
enlists both left and right transducers to contribute to
bass portrayal, instead of relying only on the right-side
transducer to huff and puff the low notes. In the Honeck
version of the Beethoven cycle, the deep growl of bowed
double basses moved and swung left-to-right-and-back
like a giant pendulum across the width of the mid freestage.
I found these to be the best audiophile versions of
Beethoven symphonies.
Observation #3
The Omega4’s staging also encompasses height
The Omega4's spatial portrayal extended in the height
direction as well. Below was how this rendition of My Girl
played out spatially:
PICTURE 9: A Distortion Of Love (Patricia Barber)
Polygram Records, 1991
Vocal images typically hover in front of my face, at the
same horizontal level. But here, Patricia Barber’s voice
hovered high up – eyeballs looking up was insufficient –
my neck had to crank up to enable me to “see” her voice.
Each time I looked up, I half expected to see the underside
of Patricia Barber’s chin. As irony would have it, my chin,
too, became involved in the proceedings – the plucking
of the double bass occurred right below my chin. The
plucked double bass was full-bodied yet airy; my jawline
felt like it was given a massage.
It wasn’t often that I came across such dramatized height
portrayals, with a vocal image so high up yet so close to
me, so much so that my neck had to crank. Most of the
time, it would be a wall of massed violins or massed brass
instruments that scaled the crowning point of a soundstage.
But usually, those walls of massed violins or massed brass
would be located some comfortable distance away from
me, mercifully saving me from any neck-cranking.
Observation #4
Staging Variability is a marker for transparency
Over months of listening, I concluded that the Omega4
had a chameleon-like staging. Below is a small sampling
of the many, many, varied presentations I encountered.
Every time I started playing a new unfamiliar album, I wasn’t
sure what I would be getting. The first few seconds would
be filled with fresh anticipation.
PICTURE 10: HEADPHONE STAGING VARIABILITY
Headphone Staging Variability (HSV) refers to the range
of possible staging types that a headphone can portray. A
headphone with a high HSV is chameleon-like in its staging.
Diagram above shows the HSV of the Omega4. The orange
vertical band shows all possible zones you might find a
sonic image via the Omega4. The Omega4’s full range of
variability goes from straight headstage all the way to
distal freestage, with its default home being the halostage.
HSV is a marker for transparency – a highly accurate
headphone will have a high HSV. I suspect that with HSV,
it is possible to compare headphones without having
them side-by-side. If Headphone A portrays all sorts of
staging shapes and sizes (recording-dependent), and
Headphone B is more limited in its variability across
recordings, then Headphone A is the more transparent
one.
_______________________________________________
SECTION 3
COMPARISON OF OMEGAS 1,2,3,4
_______________________________________________
I now feel ready to compare the Omega4 to the three
earlier siblings. Without an adequate framework to cope
with the Omega4, it would be difficult to compare the
Omega4 with its siblings. But now I have an adequate
framework.
I own all four models. However, I do not own nor have I
heard the secondary off-shoots, eg the Mk2 version of
Omega2 and the Mk2 version of Omega3.
All four of my Omegas are in good working order, inc
my 31-year old Omega1. (Whenever unused, they were
kept in a humidity-controlled, temperature-stable, dust-
free, UV-free storage solution all these years.)
Although I was familiar with the sound of the three
Omegas, I needed all four of them to play by the same
playbook. Hence I re-listened to all three earlier Omegas
with my upgraded system as well as with a VIRAS-free
protocol.
THE FOUR OMEGAS –
HISTORICAL CONTINUITIES AND DISCONTINUITIES
I referred to the four models as “Omegas” as if there was
an unbroken historical continuity from one to the next.
The reality is: the historical passage of the four models
is characterised by continuities as well as discontinuities.
PICTURE 11: MODEL NAMING, DIAPHRAGM DIAMETER, WEIGHT
Model naming seems to be marked by discontinuity.
The first model had only a Greek alphabet (“Omega”)
for its name. The next two models formed a continuity
(007 then 009), but this continuity was interrupted by
the 4th model (X9000). To be sure, there is nothing
unusual about manufacturers ending a name line and
starting a new one.
More interesting is the diaphragm diameter: one might
expect a continuity - Omega1 with the smallest diameter,
then Omega2 slightly larger diameter, and so on. But
that's not what happened. Omega1 and Omega4 have
large diaphragms (90mm diameter), while Omega2 and
Omega3 have smaller diaphragms (78mm diameter).
Stax’s promotion pamphlet for the Omega4 does mention
that the Omega4 was a conscious return to the large
90mm diameter roots.
The diameter was reduced from 90mm to 78mm when
Stax found that the process of hand-assembling the
large-diameter Omega1 eventually proved untenable as
a production protocol. Omega1 was discontinued after
only 5 years, replaced by the small diameter Omega2
in 1998. Omega3 continued the 78mm approach.
When Stax solved the challenges related to production
of large diaphragms, the Omega4 arrived. Omega 1 and
Omega4 are both eager to portray images in the halostage
and freestage. I speculate that the large diaphragm of
Omega1 and Omega4 is cause for their staging prowess.
STAGING OF THE FOUR OMEGAS
PICTURE 12: staging of the four Omegas
So how did the four Omegas compare, when playing
distance-miked recordings? I must admit to being VERY
surprised that the Omega2 and Omega3 were capable
of out-of-the-head imagery! My memory of them was
that they were headstagey headphones (especially
Omega2).
But once I played them through my upgraded system
and in a VIRAS-free manner, they showed me that they
too were capable of out-of-the-head imagery, albeit in
a reduced manner compared to Omega1 and Omega4.
Omega1 more clearly portrayed the Sense of Venue out in
the freestage than Omega2 and Omega3. But the Omega4
was capable of not just locating ambience out in the
freestage, but it also portrayed Textural Cores and Bodies
out in the freestage more palpably.
When it comes to close-miked recordings, Omega 2 and
Omega 3 tended to portray straight headstages and
curved headstages, while the Omega 1 and Omega 4
tended to portray curved headstages and halostages.
HSV OF THE FOUR OMEGAS
PICTURE 13: Staging Variability of the four Omegas
Omega1 and Omega4 have the widest variability of
staging, from recording to recording. With these two
models, the Sense of Venue could change drastically
from recording to recording. If the recording contained
strong ambience cues, Omega1 and Omega4 allowed
me to “see” the far end of recorded venue located some
say 8 feet from me (distal freestage).
The Omega3 presented less variability than Omega1 and
Omega4. The Omega2 displayed the least variability of
the four models.
RELAXED CLARITY & BACKGROUND BLACKNESS
PICTURE 14: relaxed clarity and background blackness
Relaxed clarity is high up there for me as a strength for
a headphone to have. Of the four, Omega1 was the least
relaxed, because its background between upper-mid notes
was not as black as the other three Omegas. I found the
Omega2 to be a improvement over the Omega1 in this
aspect of background blackness and hence relaxed clarity.
I did find the Omega3 to be slightly less relaxed than the
Omega2, if only because the Omega3 was more upfront,
less laidback in its presentation style. Among the four,
the Omega4 is in a class by itself - it has more clarity yet
is also paradoxically more relaxed, than the other three.
I found that there isn’t just one type of background
between notes. Rather, there are 3 types:
i. background btw treble & upper-mid notes
ii. background between midrange notes
iii. background between bass notes
Omega4 is audibly superior to Omega1 when it comes
to the background blackness between upper mid notes.
I suspect this is the dividend payoff from the Omega4’s
slanted protection mesh, which Stax says reduces
reflections from the mesh back into the listener’s ears.
With the Omega1, the background between upper mid
notes is not as black as the Omega4’s. I speculate that
reflections from the protection mesh is involved in
reducing the sense of background blackness in the
upper-mids and highs. Perhaps a resourceful modder
might one day come up with a DIY'ed Omega1 with
angled protection mesh (!)
TONAL BALANCE & HARMONIC RICHNESS
I would describe Omega1 and Omega4 as being tonally
neutral, while Omega2 is dark and Omega3 slightly bright.
Omega2 is darker than Omega3 is bright. But a description
of the overall tonal balance is insufficient to explain
another aspect where the Omega4 stands heads and
shoulders above all three: harmonic richness.
Harmonic richness is where a pianist hits, say, the
middle-C key, and a rich pallete of undertones and
overtones accompany the primary note.
PICTURE 15: tonal balance and harmonic richness
The Omega1 is a rich midrangey headphone: the middle-C
comes off pure. Omega2 thickens the undertones quite
substantially. Omega3 has a very slight treble lift to the
overtones.
But it is the Omega4 that trounces all three siblings –
there is a so much richness to the undertones and
overtones. If I listened to each headphone separately,
I might not have noticed this. But quick-swopping
between them made the Omega4’s incredible harmonic
richness obvious. Omega1 is neutral, but Omega4 is
neutral with much richer lower and upper harmonics.
FOUR SONIC PARADIGMS
PICTURE 16: four sonic paradigms
I tend to see any headphone as belonging to one of four
possible paradigms. I see the Omega1 and Omega4
belonging to the Spatial paradigm.
I see the Omega2 belonging to the Lyrical paradigm. The
Lyrical paradigm is a paradigm that values smoothness,
mellifluousness; such a headphone carries the lilt and
tunefulness of music.
I see the Omega3 as somewhat belonging to the Detail
paradigm. In this paradigm, details are brought upfront
to the listener’s attention. Strangely, although I categorise
the Omega3 under the Detail paradigm, it is actually
not as detailed as the Omega4. The Omega4, although
more detailed, does not push the details to your face.
The Omega3, on the other hand, does give an impression
of serving details upfront to the listener’s attention.
I don’t see any of the four Omegas belonging to the
Rhythmic paradigm, which values physicality and slam.
WHERE IS STAX GOING FROM HERE?
PICTURE 17: release timeline of Omegas
Stax seems to introduce a new flagship model at the
start of each new decade. (The outlier is the Omega2,
a case of emergency premature birth.)
Should we expect a new flagship in the early-2030s? Will it
be an Omega of 90mm diameter? Maybe larger diameter?
(If 90 is better than 78, wouldn’t 102 be better than 90?)
Or maybe the next flagship is not even an Omega, but
an outsized Lambda? Or something totally new?
My hope is that at the very least, Stax takes the large
diameter throughline from Omega1 to Omega4 and
continues from there, rather than from the 78mm diameter
throughline from Omega2 to Omega3. But it is really not
up to me or to any of us - each manufacturer has to
compete in the marketplace and make their own strategic
decisions.
SUMMARY FOR OMEGA4
The Omega4 is a groundbreaking headphone in a deep
personal sense. I already have 45 years of immersion in
this headphone hobby. By all accounts I should not be
this excited about a new headphone on my 45th year in
the hobby.
The Omega4 began as an affront to what I thought I knew
(“all headphones are necessarily headstagey”) and ended
as a headphone that changed my understanding of how
sound works. It made me adopt/formulate new conceptual
frameworks to deepen my enjoyment of the hobby.
SUMMARY (FOR ALL HEADPHONES GENERALLY)
I highly suspect that all headphones portray images in
the halostage and freestage if we only gave them the
chance to do so. I base my suspicion on 3 things:-
i. my Omega2, which I thought of as being headstagey,
suddenly could portray out-of-head images, once I gave
it a chance
ii. I notice Youtubers sharing similar observations too.
Sajid Amit mentions the Abyss 1266 Phi TC and the Raal
SR1a as both being able to project out-of-the-head.
ConvinceMeAudio often points his finger mid-air to
describe specific sonic images floating in space.
iii. I once demo'ed console gaming headphones -
sure enough the roaring monster and shrieking damsel
were "out there". And this was just a $100+ headphone,
hardly high-end.
So yes, I think all headphones can project out-of-the-head.
You only need two ingredients:-
i. distance-miked recordings
ii. orient your head/body formally in your listening space
and look straight at the opposite wall.
Footnote 6 contains a series of tracks that you can play
over your headphones at home, to hear (and see) for
yourself.
____________________________________________________
SECTION 4
FOOTNOTES
____________________________________________________
This section is more technical; it goes into the whys and
hows of things. I did not want such technical explanations
to interrupt the flow of the main essay, which was why
I extracted the technical bits and placed them into this
Detailed Footnotes section. It was a thrilling adventure
for me to understand how a headphone projects out-of-
the-head images, such that I can "see" images in front
of me.
____________________________________________________
Footnote 1
HOW ARE HEADPHONES ABLE TO PROJECT
OUT-OF-THE-HEAD IMAGES ?
Sonic depth is analogous to visual depth, so I will use visual
metaphors to explain:
PICTURE 18: mono versus stereo vision
In stereo depth, left and right eye see two different versions
of the world. Your eye/brain interface brings the two disparate
images together, and you see real three dimensional depth.
In mono depth, left eye and right eye see the same thing.
Same with our ears. The left ear and the right ear hear
two slightly different versions of the world:
- volume difference between left and right ear (ILD)
- arrival time difference between left and right ear (ITD)
- frequency difference between left and right ear (HRTF)
PICTURE 19: stereo hearing arises from ILD, ITD and HRTF
The frequency balance difference arises because sound
has to negotiate around facial features (nose, cheeks,
forehead) to get to the ear on other side of your face.
As the sound travels to your other ear, your face changes
the tonal balance of that sound. Your brain then looks at
the tonal balance of the right ear and the left ear, and
computes the difference. This difference then allows your
brain to estimate the position of the sound source. Your
ear/brain interface takes all three data sets (ILD, ITD and
HRTF) and establishes the 3D distance of the source.
A pair of microphones mimics your pair of ears:
PICTURE 20: distance-miked recordings
In the diagram above, a pair of microphones records
the sonic world. Left microphone captures a set of levels
and arrival times; right microphone captures a slightly
different set of levels and arrival times. ILD and ITD are
both captured.
A headphone is an inverse-microphone. The left
headphone plays what the left microphone captured,
while the right headphone plays what the right microphone
captured. The headphone recreates the recorded venue.
The distance between microphones and performers
becomes perceived as distance between the headphone-
listener and the sonic images hovering in the freestage.
For orchestral music where distances are large between
microphone and performers, the wavefront approximates
that of a source located at infinity. The two paths are
almost parallel, so sound does not have to negotiate
around facial features to get to one ear or the other.
For such faraway sources, HRTF becomes less relevant.
PICTURE 21: faraway sound sources relative to head
This was why I experienced “binaural sound” so often
via the Omega4s while playing normal non-binaural
distance-miked recordings. In the opening paragraph of
this essay, I called them "closet binaural recordings".
In truth, they were recordings that contained ILD and
ITD information, which was sufficient to create images
that I could "see" hovering in the halostage and freestage.
Binaural recordings contain ILD, ITD and HRTF information,
but the HRTF component is not crucial when it comes
to distance-miked recordings of faraway sources.
PICTURE 22: close-miked recording of an orchestra
Now on to close-miked recordings. Picture above shows
an orchestra recorded with multiple microphones, each
positioned close to instruments. In effect, each instrument
section is recorded with a single mono microphone.
Being mono, ILD and ITD are not captured. The whole
orchestra is recorded by an army of mono microphones.
Each mono signal is then brought together at the mixing
console, where an engineer assigns the position of each
instrument along a left-to-right continuum. He/she is
unable to assign position along the front-to-back axis,
because ILD and ITD information is missing.
The resulting presentation will be headstagey over
headphones. Each sonic image, being devoid of ILD and
ITD information, will unavoidably be cocooned inside
the headstage.
____________________________________________________
Footnote 2
OMEGA4 IS NOT SPEAKER-LIKE;
IT IS AN INVERSE-MICROPHONE
This observation is the most nuanced insight of this essay.
The Omega4 was not trying to be “speaker-like”; it was
simply being an inverse-microphone.
Being speaker-like would mean that the soundfield was
detached from me and "came at me" from the front. But
this was not what happened with the Omega4.
Rather, the Omega4 was immersing me in the soundfield
of the recorded event. Diagram below clarifies:
PICTURE 23: immersion of the headphone-listener in the soundfield
Diagram A shows a trumpet plus venue reflections. The
microphones pick up the direct sound of the trumpet, and
also the reflections from the recorded venue.
Diagram B shows the inverse condition during playback.
The headphone-listener hears the recreation of the recorded
event. He hears the reflections coming at him from all angles
(the reflected soundfield). The soundfield is not detached
from the headphone. He is immersed in the soundfield.
Diagram C graphically simplifies what's going on. The
trumpet sound is shown in 3 shades of orange:
- Textural Core (the sharp textures of the instrument)
- Body (the main body of the sound of the instrument)
- Sense of Venue (airiness, ambience)
Only Textural Core and Body can ever be hoped to be
free of the head. The 3rd component (Sense of Venue)
will always be tethered to the headphone listener’s head.
With headphones, there will always be a sense of immersion
in the recorded event.
An insistence that the headphone does not have any
soundfield around the head is effectively an insistence
that the soundfield does not reach the microphones.
(But if the soundfield did not reach the microphones,
how was the musical event ever be recorded?)
Hence all the diagrams in this essay that show out-of-
head images in the halostage and freestage must be
read with the understanding that the 3rd component
(Sense of Venue) remains a head-immersing soundfield.
The headphone listener will always experience his/her
head being immersed in a soundfield, no matter that
Textural Cores and Bodies are out there in the freestage.
The experience of listening to acoustic recordings via
high end headphones is thus fundamentally different
from that via loudspeakers.
The Omega4 is steadfastly not speaker-like. It is simply
an inverse-microphone, albeit a highly transparent one.
____________________________________________________
Footnote 3
BINAURAL versus NON-BINAURAL RECORDINGS
I did not find binaural recordings to have any special
stranglehold on out-of-the-head imagery. Many non-
binaural recordings gave me out-of-head imagery via
the Omega4.
I was able to put this to the test. I own both the binaural
and non-binaural versions of Chasing The Dragon’s
production of Bizet’s Carmen Habanera.
The Habanera piece was sung by Rosie Middleton,
accompanied by the National Symphony Orchestra,
conducted by Debbie Wiseman.
It wasn’t as if they recorded the performance in stereo
one day, and in binaural another day. Here was a rare
example of a performance captured simultaneously by
binaural and non-binaural microphones. The binaural
microphone and the stereo microphone were both
placed at the same distance from the performers.
PICTURE 24: non-binaural versus binaural recording
Both recordings yielded out-of-the-head imagery via
the Omega4. In fact, they sounded close, and I needed
to do A-B swops to discern the differences.
Key observations:-
Firstly, the binaural version had Bodies with more volume
and size.
Secondly, the cellos at the right side genie zone did get
sucked into the right earcup; I was hoping binaural
recordings could avoid the genie trap. It does appear
to me that irrespective of whether the microphone is
binaural or stereo, the microphones closest to the
musicians seated at extreme left or right have to be
carefully positioned to avoid the genie trap.
Thirdly, the non-binaural version had deeper freestage
depth. The binaural version had wider freestage width.
My broader observation has been: in non-binaural
recordings, perspective recedes in a more accelerated
way (photography buffs might know that wide-angle
lenses also present accelerated perspective). Binaural
recordings do not seem to present such dramatized
perspectives.
Lastly, both versions had the plucked violins located
just outside the left earcup. Bowed violins sounded
further away, whilst plucked violins were located much
nearer. The same instrument could be “seen” to be
further or nearer depending on how it was played!
This was consistent with some other albums I played:
in a Lord of the Rings cover version, in the scene where
he was newly crowned, Aragorn sings an Elvish poem.
Because the recitation was sung slowly, it was easy for
me to differentiate the Elvish vowels and consonants.
I noticed that when a vowel was sung, the vocal image
was located 4 feet from me, and when a consonant was
sung, the vocal image moved 1 foot closer to me, then
back again when the next vowel was sung. It appeared
to me that texturally-sharp sounds (such as consonants)
moved closer to the headphone listener.
____________________________________________________
Footnote 4
CROSSFEED ON DISTANCE-MIKED RECORDINGS
The Omega4 gave me confidence to make observations
about various aspects of staging over headphones. One
of the things I was very curious to try was crossfeed,
having not tried it before.
Roon has a DSP-based crossfeed facility, which I excitedly
experimented with.
I found crossfeed to drastically reduce perception of 3D
depth. Once Roon’s crossfeed DSP was switched on, I
found the sense of airiness and 3D imaging collapsed.
The reason is: stereo-aural depth (of distance-miked
recordings) requires the right and left channels to carry
completely different signals. There are level differences (ILD)
and timing differences (ITD) between left and right channels.
Stereo-aural depth works if the left headphone plays what
the left microphone picked up, and the right headphone
plays what the right microphone picked up.
Bleeding a small percentage of one channel into the other
blends the level difference between left and right (ILD),
but completely garbles the timing difference (ITD).
Timing-wise, the sound of an instrument reaches say the
left microphone either at Moment X or Moment Y, rather
than a blended moment of X and Y. A blended moment
(time smear) runs contrary to how the brain prefers things
to work.
____________________________________________________
Footnote 5
MULTI-MIKED RECORDINGS (POP, ROCK, EDM, etc)
It is easy to mistake close-miked recordings (pop, rock,
rap, EDM, etc) to be stereo recordings. In truth, these
weren’t recorded in a genuine stereo manner.
Stereo does not mean left-to-right distribution; stereo
means depth information is encoded as level difference
and arrival time difference between left and right channels.
Close-miked recordings in fact involve an army of mono
microphones. Typically, one mono-microphone is deployed
per voice or instrument. The recording engineer then
distributes the disparate mono signals across a left-to-right
continuum. He/she also modifies each mono signal using
an array of tools, eg reverb specifics, tonal adjustments.
The recording engineer, through a series of creative
decisions, constructs the fictional soundstage. I do not use
the word "fictional" in a derogative way. I use "fictional"
in the sense that creative agency is involved in crafting
something that did not exist beforehand.
Because each mono-mike is placed near each performer,
the resulting images of the performers will unavoidably
be located in the headstage. When you are listening to
a “stereo” pop recording you are in effect listening to a
series of mono images distributed across the left-to-right
real estate of the headstage. The soundfield is head-
hugging because the recording is essentially mono. (The
moment the recording is genuinely stereo, the images
move out of the headstage and into the halostage and
freestage.)
Music that inhabits the halostage and freestage is not
superior to music that inhabits the headstage. Distance-
miked music is not superior to close-miked music. Many
expressive forms of music require performers to get
close to the microphones to capture the inflections,
expressions or emotional intensity that are intrinsic to
their music-making. Think of the many, many, history-
making recordings – many were close-miked recordings.
This essay focuses on distance-miked music as a sonic
starting point that causes headphones to create out-of-
head images. The essay is not saying that close-miked
music is inferior, which is plainly untrue.
____________________________________________________
Footnote 6
TEST TRACKS TO TRY AT HOME
These are for you to try over your headphones at home.
Search your streaming platform for these keywords.
Play the Headstage version first, then the Freestage version.
The contrast, the sudden opening up, the sudden leaping
forward of the images from headstage to freestage, will
be dramatic.
MAY IT BE (cover versions of Enya's haunting song)
Headstage version: Harley Westenra
Freestage version: Boston Symphonic Orchestra
CARMINA BURANA (opera, Carl Orff)
Headstage version: Niklaus Aeschbacher
Freestage version: Saint Louis Symphony Orchestra
ALA TURCA (piano, Mozart)
Headstage version: Friedrich Gulda
Freestage version: Kristain Bezuidenhout
MADAME BUTTERFLY (opera, Puccini)
Headstage version: Victoria de los Angeles
Freestage version: Teatro Reale dell'Opera di Roma
FLIGHT OF THE BUMBLEBEE (orchestra, Rimsky-Korsakov)
Headstage version: Erick Friedman, Brooks Smith
Freestage version: Sinfonia Lahti Cello
____________________________________________________
Footnote 7
MY SETUP
Source components are the Grimm MU-1 streamer and
Mola Mola Tambaqui digital analog converter. The MU-1
connects to the Tambaqui via Furutech’s flagship aes/ebu
cable. The Tambaqui connects to the Stax SRM-T2 via
Audioquest’s flagship interconnects. All components
(including the T2) get power from Audioquest’s smallest
power conditioner (Niagara 1200).
Only the MU-1 is connected via ethernet to the router;
the Tambaqui is not. This ensures that the MU-1's output
indeed goes out via its FPGA resampling facility. (In the
"Identify" settings of Roon, Grimm was not one of the
available options. I identified the Grimm as a Mola Mola
product - only by doing so could I get the Grimm to
circumvent Roon and hence send its output via aes/ebu.
If you own a MU-1, make sure your DAC is not connected
via ethernet to a router.)
The sonic improvements brought about by the MU-1/
Tambaqui have been very satisfying – more relaxed,
more spacious, more precise positioning of Textural
Cores and Bodies. In fact, inserting the MU-1 has been
revelatory; it convinced me that achieving zero-jitter
does mean that time coherence is better preserved
(hence ITD information is more accurately portrayed –
leading to more accurate imaging in the halostage and
freestage).
Each component sits on a set of 4 magnetic levitation
feet. Each foot has a 10kg load capacity. I used to have
an audio rack with fussy little springs and ballbearings.
I got rid of that rack and opted instead for magnetic
levitation instead. I did not hear any sound deterioration,
plus I preferred the naked look of one component sitting
(floating) on another component below.
For 30 years my system had always revolved around the
Stax SRM-T2 amp. I have upgraded my DAC four times
over this period. I have changed my headphones from
Omega1 to Omega2 to Omega3 to Omega4. But the
T2 has remained a constant.
This has resulted in me remaining within the Stax
headphone ecosystem for 30 years. I have only ever
bought a new headphone once every decade. Apologies
for being unable to furnish any insights into other
headphones.
Cheers and happy listening, everyone.
__________________________________________________________
Last edited:
There are some corrections regarding the diaphragm size. 009 is about 80mm, which is slightly larger than 007 (78mm). X9000 is 86 or 87mm if I remember correctly.
