The DIY'rs Cookbook

[johnjen]

Well tonight as I type this the Orange fuse is lighting up the SQ, as in, there is moar THERE, There.
There is a sizeable increase in visceral impact from bass in particular but is not limited to just that range of the audible spectrum.
This translates as; each 'voice' has more 'authority', REALNESS, presence in the 4d space, but neither does any voice 'step on' any of the other 'voices' either.

AND I got the 1st pic of the build of my new OPT for the Purp-Amp.
To wit…

The original pic has additional resolution so you can see each individual wire of that wrap.
In a word, 'Impressive' (hear it in Darth Vaders Voice…)


JJ

 

[johnjen]

And now these OPT's are ready for testing and the final assembly.

They are made with big nanocrystalline cores and use OCC copper wire.

I'm a think'n these custom OPT's, which are designed just for this amp, are gunna push the SQ over the top and finalize this amp project.

I'm just itch'n to install them in the Purp-Amp and hear the differences between good and exceptional OPT's.

JJ

 

[Tjj226 Angel]

And now these OPT's are ready for testing and the final assembly.

They are made with big nanocrystalline cores and use OCC copper wire.


I'm a think'n these custom OPT's, which are designed just for this amp, are gunna push the SQ over the top and finalize this amp project.

I'm just itch'n to install them in the Purp-Amp and hear the differences between good and exceptional OPT's.

JJ

And to think that some people spend thousands of dollars flying to france to go see the Mona Lisa when all they have to do is buy some transformers to see real beauty.

 

[bcowen]

And to think that some people spend thousands of dollars flying to france to go see the Mona Lisa when all they have to do is buy some transformers to see real beauty.

ROFL!!!

 

[BIG POPPA]

And normally this is a Tuesday................

 

[johnjen]

Um that seems a bit obscure, so ya wanna explain?

JJ

 

[BIG POPPA]

Um that seems a bit obscure, so ya wanna explain?

JJ

The things we do day in and day out in this hobby.

 

[johnjen]

tLFF and It’s Relatives
In 4 Parts – Describing my investigations, findings, and significance of this well known yet little understood common audio complaint.

Drilling down into tLFF (the Listener Fatigue Factor)

Part 1

So back in 2015 I wrote a few posts that wound up in the HD800 thread, and until the other day when I stumbled upon my stored links to them, they had remained buried and forgotten about.

Until now…

An interesting subject, Listener Fatigue…
Everyone has heard of it, or knows what it is if they have spent too many hrs listening to music and they just need to stop and take the HP's or IEM's out and 'go quiet'/do something else, for a while.
Listener fatigue is when you reach for the DRC (Dynamic Range Control, aka, the volume control) to turn it down because there is an 'irritation' of some sort.
It may not be eye squinting nor face scrunching but somethin' just ain't right…

It's kinda like that 4 letter word describing the content in adult magazines, we just know it when we hear it.

tLFF is or can be subtle but can become rather apparent especially during longer listening sessions.
But very few have a 'definition' of just what constitutes Listener Fatigue, where it comes from, or how to lessen its affects etc.

And as I continued on my journey to learn what I could, I found some deep insights and how I could use tLFF to my advantage and apply what I learned along the way to improve my SQ.

So these next few posts are what I learned when I jumped down this rabbit hole.

My original writeup started out with a comment by @knowhatimean that I answered concerning the influence that external grills have on the soundstage and other factors such as the common use of foam and other dampening materials to quell the ‘bad resonances’ of the HD800.

“knowhatimean said:
There is a reason it sounds wider. Some of the available "width" info is being "masked" be the "resonance" that the grilles were causing.(Spatial cues are much easier to hear when you start removing mechanical colorations that the headphones are producing)

Joni Mitchell sums this up perfectly in the lyric from "Big Yellow Taxi" …”You don't know what you've got til it's gone !””

And my (edited) reply…

Um, that may or may not be the ‘source’’ of the pinched width of the sound stage.

My SAA modded 800's have no shelf liner, creatology foam, felt, nor inner covers, and the spatial cues are pinpoint precise and expansive, where the recording calls for such.

I suspect there are 'other' influences at play.

But what I do notice as a result of all of these (Anax & SAA) mods, is a major reduction in tLFF, which 'allows' me to turn up the DRC, to 'higher' levels before I reach 'too much' and don't wish to go any higher, mostly due to the lack of ‘comfort' level of the SPL (Sound Pressure Level).
When tLFF is improved, by whatever means, the SQ raises accordingly.
I hear this as an increase in the degree of being ‘in focus’, for the entire acoustic presentation.
And interestingly, as tLFF is improved, this 'additional' degree of being ‘in focus’ remains quite evident, even when the DRC is lowered.

What this allows is a greater dynamic range in the playback of the music, which in turn increases all of the subtle cues (spatiality, and all the other related harmonics associated to each instrument/voice), not to mention better bass due to our hearing's natural volume increase of the low end, as the overall SPL is raised.

And there seems to be another 'mechanism' at play as well.
As the ‘Choke Points' (CP’s) in the entire system are ameliorated, the overall 'get out of its own way' factor 'allows' for a more accurate original signal to arrive at the transducers, in the first place.
And.
As we reduce the transducers ‘unwanted/undesirable’ acoustic 'traits', this can also 'allow' more of the actual signal to be heard, because these ‘bad’ traits no longer act as a 'mask', which means the need for further masking the mask, can become both unnecessary to begin with, and unwanted.

But as we all know improvements to the transducer (speakers, headphones) are usually the most effective.
And these types of mods, such as adding masking with foam/felt, experimental removal of 'extra' parts (grills, etc), have been popular forever.
And further it is also commonly held that these sorts of improvements can sometimes be quite significant, as is the case before us.
So it can be a challenge for us DIY’rs to figure out the ‘best’ balance between different mods.

Which has led me to the understanding that as further CP’s are removed from the system, it is able to resolve to even greater degrees of inner definition, and be able to deliver 'more' of each instrument/voice, with a greater sense of acoustic 'realness' as the level of precision and resolution is increased.

And there is another thing I’ve noticed, namely, as our systems become more and more precise and resolving, it becomes all to easy to assign causation of the undesirable sonic traits, to an incorrect originating source of the 'irritation'.
But not always…
For instance, some believe the 800's have a 'resonant?' peak in the ≈ 5-8KHz region and that is the source of their ‘problem’.
Or (fill in your favorite example here)…

But with any reduction of the causes of tLFF, the apparent overall sound level seems to lower at the same time that the DRC has been raised. Which is rather curious, if you think about it. (I raise the DRC and the volume seems to lower????)

Because now, to reach the same level of tLFF as before the last improvement to tLFF, the DRC needs to be increased, even further…

It sounds like the acoustic presentation seems to present less ‘energy’ (SPL). And due to the reduction of the causative factors of tLFF and other CP’s, the available acoustic energy seems more tightly ‘bound’ to its original ‘parent’/source.

Which points back to the perceived decrease in the Dynamic Range, because while there is less ‘smeared’ acoustic energy (since more of it is ‘bound’ to its acoustic source), the amount of silence between individual notes for each instrument/voice/source of acoustic energy, has increased.
And so there is a greater amount of time where less acoustic energy is being generated, and we can perceive this as lower SPL.

IOW, when the total amount of available acoustic energy is aligned and associated more precisely and accurately with its original source, there is more complete coupling of the original sonic signal to its re-created acoustical parent, which also means there is less acoustic energy where it doesn’t belong.

Which is another way of saying the sound level seems to drop due to the reduction of tLFF, as the entire system has gotten ‘out of it’s own way’, all the more.

And, "You don't know what you've got til it's gone !" indeed! :thumb


This was the introduction to the next part which gets much more involved and lengthy.
So I turned it into two separate posts, and added an addendum which makes this a 4 post topic.


So on to part 2.

JJ

 

[johnjen]

Drilling down into tLFF (the Listener Fatigue Factor)

Part 2 of 4 – Describing my investigations, findings, and significance of this well known yet little understood common audio complaint.

Hmmmm, let’s see…

I stumbled upon tLFF as I was tracking changes, over time, of the SQ of my system as it ‘aged’, while performing ‘experiments’. I noticed that sometimes I could crank up the DRC (Dynamic Range Control, aka volume control) way more than other times before a degree of listener discomfort kicked in. So I started to track this ‘variability’ in my daily log.
And what I started to notice were the patterns I mentioned in part 1 of these tLFF posts.
Namely as tLFF was lowered, I could crank up the DRC more than when tLFF was ‘high’.

IOW, right from the start as tLFF was lowered the DRC could be increased, and vice versa.

But what I came to realize was the reason the DRC went up is because the acoustic energy was more closely coupled/bound to it’s parent/‘source’, which is what happened as tweaks and such were made. These changes, after ‘settling in’, resulted in lowering tLFF.
This resulted in closer coupling of all the acoustic energy that an instrument makes such that it is more precisely timed and presented to my ears, and this results in the actual acoustic musical signal being more faithful to the original. Not in terms of FR but rather in the presentation of the dynamic energy of the instrument that I hear.

An example.
Stick your head near a piano or drum set or other percussive instrument while it is being ‘vigorously’ played. What you will experience is the ‘power’ of the impacts, the percussive effects, the energy that is being created and ‘imparted’ into the acoustic environment.
This creation and release of energy, is based upon the excitation of ‘tuned’ resonant components that further create sub and supra harmonics which are all ‘created’ as a direct consequence of the initial energetic injection of power by the musician.
Namely when the stick hits the cymbal or drum, the hammer hits the string, etc. This ‘starting point’ for that note, and especially the subsequent harmonics that are created, are what we use to identify not just what the instrument is but which note, how ‘loud’ it is, what the acoustic environment is, how near or far away in 3d space, etc.

We can identify these things because we have previous experience (we ‘learned’) what the acoustic ‘thumbprint’ for a particular instrument sounds like. And as this acoustic signature is changed, by whatever means, there is a deviation from original acoustic energy signature.
IOW we can tell a tack piano from a grand, from a standup etc. and we can tell when it is close miked or from a greater distance away because the resultant sub and supra harmonics change accordingly.

All of these subsequent harmonics are created and released into the acoustic environment in their proper time, because they are a function of the creation of that initial energetic pulse and are ‘time aligned’ to that source.
IOW they are bound to it, because they are created by it.

When this subtle time aligned acoustic collection of frequencies are skewed or delayed or stretched out thru time, the original acoustic energy has now become ‘smeared’ and no longer properly combines all the acoustic energy to that of it’s parent.
IOW the acoustic energy we hear being presented to our ears is out of synch from it’s original creation.
This ‘smearing’ or spreading out the acoustic energy tends to ‘fill in’ where there should be a lack of energy or where that energy simply didn’t originally exist in the first place during the dynamic creation of the original signal.
This makes the original source sound out of focus, as in, the subtle cues and harmonics are ‘Fat’ or spread out.

THIS is my vote for tLFF

Where the acoustic energy is not presented ‘properly’, either by omission or by being ‘out of synch’, because either it does not present the full and precise original energetic acoustic signature and/or more acoustic ‘artifacts’ have been added.

And these changes/additions seems to come from 2 basic ‘sources’.
The first being the playback equipment adding ‘distortion’ of some sort, of which many are well known (IM, THD, FR etc.).
The second being a specific subset of #1, that being, that the original acoustic energy is being presented (heard) out of synch from its original source (phase shift, slew rate, zero crossover etc.).

All due to changes to the re-created signal that are heard.
Even if the original recorded signal is distorted to begin with.

Oh yes and let me be ‘clear’ here. This isn’t just about digital music playback. If tLFF truly is all about the music being out of synch with itself, think about what happens when the diamond tip ‘reading’ the groove walls isn’t aligned ‘properly’?
The 2 channels of information become ‘time smeared’ if the VTA and azimuth aren’t adjusted ‘properly’.
Think screech and tLFF gone berserk, especially on poorly recorded vinyl…
And power amps (strictly an analog device) seem to have as much of a role to play in contributing to tLFF.

And of those 2 basic sources there appear to be 2 specific contributions to tLFF that stand out.
The first factor is during the re-creation of the analog signal, and the second is during the ‘delivery’ of this signal.


On to Part 3

JJ

 

[johnjen]

Drilling down into tLFF (the Listener Fatigue Factor)

Part 3 of 4 – Describing my investigations, findings, and significance of this well known yet little understood common audio complaint.


All DAC’s use mathematics to re-create the original musical signal, likewise a diamond tip ‘reads’ the groove wall, or the tape head ‘reads’ the magnetic flux modulation, etc.
These re-creation methods and related devices are all performing a change of state from one medium to another (usually into an analog electrical signal).
And these energetic translations/changes of state from digital, or mechanical, or magnetic to electrical, along with their compliment, the electrical to acoustic energy translations, are always the most critical in terms of ‘getting it right’ (accuracy, precision, resolution, etc.).

And since this initial change of state is the very basis for the signal to start with, if it isn’t ‘properly’ handled, no amount of corrective action will ever ‘fix’ the signal. Well, other than substituting with ‘better’ devices and/or processes.

Secondly, faithfully delivering that signal and then completing this energetic change of state into acoustic pressure contributes it’s own variety of tLFF contributions.
This second contributor to tLFF is something we can actually deal with on a less than wholesale replacement of major components (amps, dacs, cartridge etc.) basis.
Indeed this is where most of my tweaking’ has yielded the most bang for the buck. And which also significantly affects new major components as we ‘upgrade’ our systems as well.
And a large percentage of these improvements are gained from the amp and its ability to ‘properly’ couple with the driver.

And what I have come to know is that as we lessen these ‘errors’ while generating acoustic pressure, and/or allow more of the original signal to come thru, tLFF is reduced and the SQ takes a mother may I step up as more and more of the available acoustic energy is aligned and then ‘properly’ presented/heard during playback.

The list of influences or tweaks I’ve experimented with, that contribute to the improvement of tLFF are, for some, hard to believe, and/or for others seem to be outright dubious.

And to make things even more ‘complicated’ there does seem to be a threshold that needs to be crossed before these changes become evident.
IOW if the system is ‘clogged’ with CP’s, (Choke Points) and unless you ameliorate a major clog, there is a good chance you may not hear any change, mostly due to masking/smearing of acoustical energy where it doesn’t belong. This is a common observation made by many who try only one ‘upgrade’ like a power cable or interconnect cable, and hear no differences. Of course there is the distinct possibility that the attempted ‘upgrade’ simply wasn’t up to the task. (i.e. it wasn’t a sufficiently better cable etc.)

But once this threshold is reached it can initiate a cascade effect where EVERYTHING starts to make a difference. But even initially this can lead to much confusion and frustration once a change IS noticed, because now determining if it is really an improvement, or just a change, becomes the deciding factor instead of just IS there any change.

And so now a whole new set of evaluatory decisions must be brought into the picture and become familiarized and applied and refined.
It’s like a whole new ball game.
And it can get complicated quite quickly as the degree of ‘the system getting out of its own way’ continues to improve which results in more and more transparency.
This is where EVERYTHING can start to loom large. And where identifying just which CP’s are making their presence heard, becomes a matter of experience.

This is precisely where the 800’s come into their own.
They are such precise transducers that even with a ‘clogged’ system, ‘artifices’ are all to easily heard and then the job at hand is to ‘fix’ the problem(s). And the more that any of the 800’s unwanted contributions are ameliorated, the more the rest of the system’s undesirable attributes come into focus. Which are sometimes attributed to the 800’s themselves. But there is usually a commensurate increase in the inner details and focus, as more and more of the system continues to ‘get out of its own way’.
And since the 800’s have a degree of precision that is highly scaleable, which can help tame some of this complexity, they can help provide a ‘stable’ reference point with from which to ‘stand on’ and proceed onward from.

And tLFF has, at least for me, become a most useful tool in terms of determining if changes made are actually beneficial improvements or are just changes. There are of course other tools that also can help and the combination of these tools allows me to more quickly determine what is a desirable change, and if an actual removal of CP’s occurred, which did lessen the tLFF’s influence.
Or not.

Another way of perceiving this is to view it as an exploration into scaleability and how well the components scale upwards together. I have come to understand that as CP’s are ‘removed’ or diminished in severity, the task now becomes how to determine if the resultant changes really are ‘better’, or not.
And when there is an obvious improvement, as in ‘OH MY DOG’, or ‘I’m hearing my music as if it were the first time’ etc. this provides solid evidence, at least to me, of a marked improvement in the overall resolution and that the system has ‘gotten out of its own way’ all the more.
IOW, scaleability just took a significant step up, and EVERYTHING sounds better.

tLFF, I5 (Intelligibility, HB&W, T3 (Head Bobbing & Weaving, Toe Tapping Time), among others, are all sure signs of improvements of scaleability.
And 800’s are hugely scaleable, and it appears more so than much of the gear available to us today.

This is a decided double edged sword in that as the CP’s and other system deviations are removed, those that remain seem to loom large(r), which can be quite frustrating.
On the other hand once a degree of resolution is reached and the SQ is refined ‘enough’, the SQ has stepped up and away from what we have experienced in the past, so now we are now exploring previously unexplored edges of the envelope.
Which means we are now navigating in somewhat unfamiliar acoustic territory.

But it also means as fewer and fewer CP’s remain, the overall SQ continues improve.
As such we are discovering new/additional nuances and subtle details of the presentation of the music, as we continue to hear it all anew, as the veils and unwanted ‘artifacts’ are removed.

This of course could be the DIY’rs curse — forever removing artifacts…
Think Sisyphus

JJ

On to the Last Part

 

[johnjen]

Drilling down into tLFF (the Listener Fatigue Factor)

Part 4 of 4 – Describing my investigations, findings, and significance of this well known yet little understood common audio complaint.

The Last Part
This is an addendum to the original posts.

It deals with a very specific type of tLFF namely overshoot.
And specifically overshoot as it applies to speakers and more pointedly at headphones.

The experimentation I focused upon with my HD800-Jmod’s Gen-6 was aimed at reducing the overshoot that was designed into them, on purpose and with intent.
I arrived at that conclusion after several years of fussing and receiving some feedback concerning some of the 800’s design criteria.

But the net effect of reducing the amount, but not all, of the existing overshoot was a HUGE reduction in tLFF, and along with the associated SQ changes/improvements that accompanied this tweak the end results are nothing short of amazing.

I have written posts that go into more detail concerning what my 800-Gen6 mod wound up being,
https://www.head-fi.org/threads/the-diyrs-cookbook.781268/page-90#post-14608836
but I found that overshoot when applied too liberally, creates significant tLFF all by itself, enough so that when significantly reduced these 800’s can simply deliver astounding SQ.

And yes far more than just the 800’s are involved, but as a major CP (Choke Point) all unto itself, its amelioration was simply a stunning SQ improvement in all areas of SQ that matter to me and remains so even as I type this.

So I consider overshoot, especially when it’s the marketing department that determines that too much is just enough, makes for a tragic choice for a design criteria for a SotA (State of the Art) piece of gear.

And while some overshoot seems to be ‘necessary’, with very few exceptions, every one of the HP’s step response that I looked at, for its overshoot characteristics, had FAR to much.

To me this one single overused design criteria is the single reason why we haven’t busted thru into that next generation of ‘Better’ SQ in SotA HP’s, that has been taunting us all for far too long now.

So to wrap up this topic of tLFF and it’s attendant acoustic relatives, when your listening sessions can go on and on for hours and your HP’s are seemingly glued to your head and there is NO DESIRE to do ANYTHING but listen to tunes, ala SDSG (SuperDuperSuperGlue) your tLFF is VERY low and that is the time to crank on the DRC and listen even deeper into the music where there be nuances to be appreciated.

Just like I like.


JJ

 

[johnjen]

NEWS FLASH…
beedeep-deep…

This just in…

My custom OPTs are in final assembly and testing and are looking good man…

And for those who understand techno-specs…
Here are the final measurements:

Low signal frequency response - 4.2Hz - 70kHz ; -3dB ; 2k Rgen ; 32R load

Primary inductance: 60.5H
Primary Idc: 20mA
Max power at 25Hz: 2.6W

Impedance ratio: 7.6k to 32R

Other possible secondary connections: 72R ; 128R

Leakage inductance = 5.4mH
Grounded secondary overall capacitance = 750pF
Cs + Ls resonant frequency = 79kHz

Primary Rdc = 184R
Secondary Rdc 32Rtap = 1.2R

And with a bandwidth of -3db from 4.2Hz - 70kHz from the 32Ω secondary taps,
and if I read the graph correctly its ≈-1dB from 10Hz to 40KHz, this is quite impressive for a set of OPT's regardless of source.

I'm jazzed to say the least.

JJ

 

[bcowen]

NEWS FLASH…
beedeep-deep…

This just in…

My custom OPTs are in final assembly and testing and are looking good man…



And for those who understand techno-specs…
Here are the final measurements:

Low signal frequency response - 4.2Hz - 70kHz ; -3dB ; 2k Rgen ; 32R load

Primary inductance: 60.5H
Primary Idc: 20mA
Max power at 25Hz: 2.6W

Impedance ratio: 7.6k to 32R

Other possible secondary connections: 72R ; 128R

Leakage inductance = 5.4mH
Grounded secondary overall capacitance = 750pF
Cs + Ls resonant frequency = 79kHz

Primary Rdc = 184R
Secondary Rdc 32Rtap = 1.2R

And with a bandwidth of -3db from 4.2Hz - 70kHz from the 32Ω secondary taps,
and if I read the graph correctly its ≈-1dB from 10Hz to 40KHz, this is quite impressive for a set of OPT's regardless of source.



I'm jazzed to say the least.

JJ

Sweet! I kind of understand some of the specs (-3 dB at 4.2 Hz? Dang!), but those look so cool the specs are kinda irrelevant.

 

[johnjen]

Yeah with under 10 hz available at the low end, my existing kicka** bass should definitely take a step up, not to mention with the use of OCC wire wrapped around nanocrystaline cores, the phase response, FR linearity, when delivered from 60H of inductance, all should contribute to a very immersive listening experience.

And yeah they visually DO look rather impressive and unique to boot.

I'm already figuring how they will look after being mounted on the top plate.

JJ

 

[bcowen]

Yeah with under 10 hz available at the low end, my existing kicka** bass should definitely take a step up, not to mention with the use of OCC wire wrapped around nanocrystaline cores, the phase response, FR linearity, when delivered from 60H of inductance, all should contribute to a very immersive listening experience.

And yeah they visually DO look rather impressive and unique to boot.

I'm already figuring how they will look after being mounted on the top plate.

JJ

But the burning question remains: have they been quantum tunneled?