snip
Possible causes for LFF huh ? Let's try this
Our ear drums need a certain amount of milliseconds to process every sound that they hear . The closer together or the longer the
duration of sounds taxes our hearing mechanisms as we've disrupted the interval of rest time our eardrums will have between these
impulses. For myself it's a matter of the duration of my listening sessions.
I simply don't care to listen at a level any louder then where I think I can hear the lowest level of sound fully at a slightly lower than medium sound level (This normally ends up being a challenge with new Orchestal recordings, so I never start listening to a new recording first). To be honest the better sounding that everything becomes the greater my challenge to not end up ear fatigued has become as I have not even realized that I've become ear fatigued sometimes until I woken up the next day.
I've listened to several things tonight were I can't recall the recorded detail ever grabbing my attention the way it did this evening.
Other than replacing my Burson Soloist hp amp with perhaps the Sennheiser HDVA 600 I'm satisfied with how "Articulate" & devoid
of non musical frequency contouring my system has become
Keep me updated on any new insights you may have regarding LFF as it's also on my radar for reasons I've mentioned
steve
Drilling down into LFF
Hmmmm, let’s see…
I stumbled upon LFF 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 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 my previous LFF post.
Namely as LFF was lowered, I could crank up the DRC more than when the LFF was ‘high’.
IOW, right from the start as LFF got better the DRC could be increased as well, 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 the LFF.
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 dynamic energy of the instrument that is presented to me.
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 power, 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 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 power 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 impulse and are ‘time aligned’ to that source.
IOW they are bound to it, because they are created by it.
When these subtle time alignments are skewed or delayed or stretched out thru time, the original acoustic energy is now ‘smeared’ and no longer properly adds it’s 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 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 LFF
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 or more acoustic ‘artifacts’ have been added.
And these changes/additions can 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.
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 LFF 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 LFF gone berserk, especially on poorly recorded vinyl…
And power amps (strictly an analog device) seem to have as much if not more of a role to play in contributing to LFF.
And there appear to be 2 general sources of these contributions to LFF.
The first source is during the re-creation of the analog signal, and the second is during the ‘delivery’ of this signal.
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 vareity of LFF components. This secondary contributor to LFF 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, LFF 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 LFF are, for some, hard to believe, 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 ‘choke points’, 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. (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.
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 ‘choke point’ is being 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 LFF 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 ‘choke points’ occurred, which did lessen the LFF’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 the ‘choke points’ 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.
LFF, 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 choke points and other system deviations are removed, the more 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 ‘choke points' 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
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