CHANGSTAR: Audiophile Headphone Reviews and Early 90s Style BBS

Lobby => Soapbox => Topic started by: DGCFAD on April 18, 2015, 06:39:56 PM

Title: In Defense of High Fidelity
Post by: DGCFAD on April 18, 2015, 06:39:56 PM
 p:0 I wrote this a couple of months ago for some of my musician friends and the audio community at large, thought I'd reprint it here.

In Defense of High Fidelity
An Audio Argument by Gary Barker

Yesterday, a musician friend sent an audiophile friend an article which put forth the argument that given the current state of and trends in contemporary music along with modern recording techniques it was impossible to hear the difference between 8 bit and 16 bit recordings, and the article went on to provide a couple of short samples to prove the author's point. The implication of the article being that audiophile recordings made in 24/192 KHz or DSD are simply a rip off and of no value (you will not see me use the term Hi-Rez audio in this article, because Hi-Rez has now been “officially” defined to mean uncompressed 16/44 KHz, which the majority of us think of as Standard-Rez audio). Of course this left the audiophile pulling his hair out and the musician smiling and nodding contentedly believing that High-end audio is simply a load of “snake oil”.

To be fair, if your total music listening experience consists of listening to amplified music in clubs with a background noise floor of 75 db, or if you are a pop musician* who knows that any noise he makes below 100 db will not be heard by his audience, the argument against high bit depth (as opposed to high bit rates, which is a different thing entirely) has very strong merits. In fact, most DJs (and teenagers) would probably benefit from converting their music to uncompressed 8 bit files over most higher bit depth compression schemes (smaller files, with minimal processing overhead, while eliminating the sonic artifacts that come along with most compression schemes).

I should also point out that I came to high-end music reproduction as a musician (although a primarily acoustic one, piano being my core instrument), and I don't really consider myself an audiophile, but more of a music lover (case in point, I now own more music than I will be able to listen to in the span of my lifetime at my current rate of consumption, but continue to collect more), though the more accurate the reproduction, the more enjoyable the experience is for me.

And that brings me to what I really want to talk about. For audio skeptics (AES engineers and their ilk),  or half deaf drummers to say that there is no difference between Mid-fi (Standard Resolution Audio) and Hi-Fi (Audiophile Quality Audio) is equivalent to saying  that there is no difference between a $2.00 bottle of wine and a $500.00 bottle of wine, or that there is no difference between a MacDonald's hamburger and five star Cordon Bleu cuisine. To a biologist, food is food, alcohol is alcohol, sound is sound, but to the refined palate, quality fare is a small piece of heaven.

Yes, like wine connoisseurs and epicureans, only a very small percentage of the people are able to fully appreciate audiophile quality sound. And like other sensory experiences, some of it can be taught, and some of it is innate ability.

Obviously, ones musical tastes is a factor, amplified music is by its nature of limited fidelity. Musical instrument amplification is chosen for its ability to create sound, rather than re-create sound, accuracy and dynamic range are rarely considerations in their selection. As noted before, music with an inherently high noise floor lacks dynamic range, which can also mask detail. Electronically generated music has no “real world” acoustic baseline from which to draw comparison, so fidelity becomes almost a moot point.

Experience is the most important factor, if you have never heard “live” music, then it is impossible to determine what is correct sound, and are left with what sounds good (to you), which drops you into the realm of Mid-fi. Along with a large mental database of “live”, preferably acoustical music performance from which to draw comparison, goes training. Almost every audiophile has had at one time a mentor to explain what to listen for.
Of course the most important factors are desire and ability. To be a connoisseur of anything, takes a certain investment of time, attention, and effort, and requires a willingness to release ones preconceptions, and rely on ones senses, which is where ability comes in, if you are incapable of hearing a difference due to physical limitations, no amount of training or experience will overcome that.

Which is a long way to return to my initial statement that audio connoisseurs are a rare breed. And though the majority of people can't hear the difference, those who can, do so consistently. Just like there are wine tasters who can identify the “terroir” of a given bottle of wine, there are audiophiles who can identify specific audio components in blind tests. And though the AES considers them to be statistically insignificant, there numbers are great enough to be the backbone of an entire industry. But, that industry will die, if the producers of the source material, decide to only cater to the mass market, providing the minimum necessary quality.

Why 24 bit? To be honest, for those of us who are fans of old analog recordings (pre-digital), we would be better served by 16/384 KHz than 24/96 KHz, but that being said, for new recordings of acoustical instruments, especially large orchestral sections, the 140 db dynamic range (even though it exceeds current amplification technologies) of 24 bit is necessary to provide truly “realistic” reproduction.

It is important to remember that a recording engineer has a secondary role as historian, and it is their duty to provide as accurate a record as current technology will allow. It is of little doubt, that technology will eventually exceed current limitations and be able to fully embrace the dynamics of 24 bit recordings.

Which brings us to sample rate. Why high sample rates if people can't hear over 25 KHz? The answer is both simple and complex. The simple answer is that the human ear doesn't work like a microphone. A microphone takes all the soundwaves that hit it and convert it to a single complex electronic signal (wave). A single note on a piano, produces hundreds of soundwaves, all well within the human range of hearing, but when these soundwaves hit the microphone, it must convert them to a single electronic signal, with harmonic overtones in excess of a MegaHertz. The human ear is more like a thousand microphones each able to process the soundwaves separately producing a much more accurate picture of the original sound, and able to sum up the harmonic overtones.

So the question becomes, how much detail can the human ear hear? A friend, who I have great confidence in, did some experiments back in the 80's listening to digitized signal from an analog Master Tape (compared to a direct feed) claimed the point at which he stopped hearing a difference was 400 KHz (though it is possible that some of this may be due to the quality of DACs at the time), others have argued that the high frequency roll off of magnetic tape is to great for this to be true, but I'm will to stick to that number, especially for live recording, where the limitations are the roll off of the microphones and electronics.

So is it “snake oil”, clearly not, that is not to say that there isn't a lot of “snake oil” out there, nothing should be taken at face value, always test it for yourself, but if you can't perceive the difference, don't be so arrogant as to believe yourself to be the ultimate authority, it doesn't work for you, move on, don't  recommend it, but don't tell people who can hear a difference that they are either being conned or lying. Do all recordings need to be audiophile quality, no, should they, yes, if we are to truly respect the art being created by the musicians, especially when considering the future historical value of master recordings, I believe we should be mastering at 24/384 KHz or DSD256 (Quad DSD).


*This is why I am skeptical of people who pick their equipment based on what is popular among pop musicians, recording engineers are a different matter (as long as you understand the reasoning behind their choices), though they rarely operate to the same exacting standard as your true audiophile or your classical musician (who in my experience have been the most exacting in their audio reproduction, if they haven't given up entirely assuming quality reproduction is impossible).
Title: Re: In Defense of High Fidelity
Post by: numbercube on April 18, 2015, 07:11:12 PM
get an Yggy, resample all your hi-res files to 16/44 or 16/48 and abx them.
Red book is all we need...
Title: Re: In Defense of High Fidelity
Post by: DaveBSC on April 18, 2015, 07:26:04 PM
But, that industry will die, if the producers of the source material, decide to only cater to the mass market, providing the minimum necessary quality.

That's an important point. The listening devices of choice for the mass market is mostly either extremely cheap headphones (usually whatever comes in the box with a phone or DAP) or laptop speakers. Once mastering engineers made the focus of their work entirely about catering to these people exclusively, at the expense of everyone who actually cares one iota about sound quality, the justification for spending any real money on audio equipment went out the window. The more resolving your system is, the worse these records sound. That's why I have to laugh at the "HD" version of something like Morning Phase, with its cobbled together mess of MP3 sourced mixes, ridiculous bass levels, hyper loud mastering, and clipping distortion. HD my ass.

Why 24 bit? To be honest, for those of us who are fans of old analog recordings (pre-digital), we would be better served by 16/384 KHz than 24/96 KHz

I'm curious, what is your justification for this? I've seen data showing a theoretical maximum dynamic range for vinyl to be around 90dB, but very few tables and carts are likely able to actually achieve that, so digitizing at 24 as opposed to 16 is probably unnecessary. It DOES however provide headroom for post processing, and there's no harm in it. Vinyl's frequency limit is likely somewhere in the 50kHz range, which 192kHz sampling covers with plenty of room to spare. I see absolutely no need for 384kHz, all that will likely do is waste an enormous amount of storage space.

So the question becomes, how much detail can the human ear hear? A friend, who I have great confidence in, did some experiments back in the 80's listening to digitized signal from an analog Master Tape (compared to a direct feed) claimed the point at which he stopped hearing a difference was 400 KHz

Bullshit. 400kHz information was not recorded. It was not stored, and it was not reproduced. High end amplifiers may be capable of that, but they will be down drastically in level compared to 100kHz, and there are no speakers or headphones capable of reproducing 400kHz, nor do traditional microphones pick it up, nor do analog master tapes support it. It didn't exist, and so it was not heard. Dogs can't hear 400kHz, and if your friend believes he can, he should be able to hear a dog whistle clear as day.
Title: Re: In Defense of High Fidelity
Post by: DGCFAD on April 18, 2015, 10:03:46 PM
That's an important point. The listening devices of choice for the mass market is mostly either extremely cheap headphones (usually whatever comes in the box with a phone or DAP) or laptop speakers. Once mastering engineers made the focus of their work entirely about catering to these people exclusively, at the expense of everyone who actually cares one iota about sound quality, the justification for spending any real money on audio equipment went out the window. The more resolving your system is, the worse these records sound. That's why I have to laugh at the "HD" version of something like Morning Phase, with its cobbled together mess of MP3 sourced mixes, ridiculous bass levels, hyper loud mastering, and clipping distortion. HD my ass.

I'm curious, what is your justification for this? I've seen data showing a theoretical maximum dynamic range for vinyl to be around 90dB, but very few tables and carts are likely able to actually achieve that, so digitizing at 24 as opposed to 16 is probably unnecessary. It DOES however provide headroom for post processing, and there's no harm in it. Vinyl's frequency limit is likely somewhere in the 50kHz range, which 192kHz sampling covers with plenty of room to spare. I see absolutely no need for 384kHz, all that will likely do is waste an enormous amount of storage space.

Bullshit. 400kHz information was not recorded. It was not stored, and it was not reproduced. High end amplifiers may be capable of that, but they will be down drastically in level compared to 100kHz, and there are no speakers or headphones capable of reproducing 400kHz, nor do traditional microphones pick it up, nor do analog master tapes support it. It didn't exist, and so it was not heard. Dogs can't hear 400kHz, and if your friend believes he can, he should be able to hear a dog whistle clear as day.

Two points, analog recordings have roll off, roll off and cut off are not the same thing, so when an analog recording rolls off at 50kHz it doesn't hit that -90db until significantly higher. And resolution and frequency are not the same thing. Resolution is the transient  differences and harmonic overtones of multiple polyphonic sounds. Your ears are able to hear multiple sounds, even if they are the same frequency, electronics are not able to do this beyond the limitation of how many channels are recorded. Instead, the electronics interpret multiple polyphonic sounds as a single complex sine wave which appears as a much higher frequency than the tones actually being produced. 
Title: Re: In Defense of High Fidelity
Post by: anetode on April 18, 2015, 10:18:44 PM
Are you fucking serious?
Title: Re: In Defense of High Fidelity
Post by: Marvey on April 18, 2015, 10:59:08 PM
So the question becomes, how much detail can the human ear hear? A friend, who I have great confidence in, did some experiments back in the 80's listening to digitized signal from an analog Master Tape (compared to a direct feed) claimed the point at which he stopped hearing a difference was 400 KHz (though it is possible that some of this may be due to the quality of DACs at the time), others have argued that the high frequency roll off of magnetic tape is to great for this to be true, but I'm will to stick to that number, especially for live recording, where the limitations are the roll off of the microphones and electronics.

Digital gear in the 80s, even the professional mastering stuff, did not go out to 400kHz. In fact, existing gear in the pro-world today doesn't go past 192kHz and many still work in 96kHz. Not to mention what DaveBSC said: amps and especially transducers don't have anywhere near that bandwidth. 400kHz is like AM radio frequencies.
Title: Re: In Defense of High Fidelity
Post by: DGCFAD on April 18, 2015, 11:30:10 PM
Digital gear in the 80s, even the professional mastering stuff, did not go out to 400kHz. In fact, existing gear in the pro-world today doesn't go past 192kHz and many still work in 96kHz. Not to mention what DaveBSC said: amps and especially transducers don't have anywhere near that bandwidth. 400kHz is like AM radio frequencies.

The tests were performed over at JPL using experimental DACs, I wasn't there, but I have no reason to believe he lied. He was one of the pioneers of digital audio, but since he is still in the business, and I have not socialized with him in over 20 years, I prefer not to give his name.
Title: Re: In Defense of High Fidelity
Post by: Marvey on April 18, 2015, 11:39:58 PM
Another problem is microphones used in the studio exhibit steep rolloff, often well before 20kHz.
Title: Re: In Defense of High Fidelity
Post by: anetode on April 18, 2015, 11:56:12 PM
The tests were performed over at JPL using experimental DACs, I wasn't there, but I have no reason to believe he lied. He was one of the pioneers of digital audio, but since he is still in the business, and I have not socialized with him in over 20 years, I prefer not to give his name.

Well thank god he wasn't one of those
AES engineers and their ilk
Title: Re: In Defense of High Fidelity
Post by: dreamwhisper on April 18, 2015, 11:56:56 PM
Just to clarify, your basis for your argument is the subjective experience of your friend?
Then right after, you assert that someone should really hear it for themselves before making any conclusions?

On a side note, if you want people to read an essay you write, attempts should be made to follow essay format.
A proper introduction paragraph, and more than just 2 sentences composing your paragraphs.

I appreciate the part about you not being an audiophile, but a music lover.
But to be perfectly honest with you, I lost about 80% of the interest I had when I saw you start comparing the art of listening to wine tasting, which seems like the perfect analogy for the audiophile approach to me.
Title: Re: In Defense of High Fidelity
Post by: Anaxilus on April 19, 2015, 12:12:14 AM
I know many of us tend to fall on one side or the other of what here has become a very refined point of razor sharp clarity when discussing what we hear versus what we measure (unlike other forums where people are all over the place). Hearing a number as big as 400khz is like exploding the argument into my friend looks like this:

(https://m0vie.files.wordpress.com/2014/01/tng-transfigurations16.jpg?w=468)

However, do keep in mind that DGCFAD is new around here and probably not used to the usual talking points and methods we've all become familiar with when discussing these things. So do try to focus on the core arguments that can be discussed constructively within the core intent of the post (which is not that humans at JPL can hear to 400khz). In the end, statements that can be washed away or ignored as easily as they can be stated are not good points to debate.
Title: Re: In Defense of High Fidelity
Post by: Marvey on April 19, 2015, 12:21:41 AM
A single note on a piano, produces hundreds of soundwaves, all well within the human range of hearing, but when these soundwaves hit the microphone, it must convert them to a single electronic signal, with harmonic overtones in excess of a MegaHertz.

That's actually incorrect and can be verified with microphone attached to a spectrum analyzer. Soundwaves add on top of each other in amplitude, not frequency.

Quote (selected)
The human ear is more like a thousand microphones each able to process the soundwaves separately producing a much more accurate picture of the original sound, and able to sum up the harmonic overtones.

That's actually incorrect as well. While individual hair cells in the inner ear are tuned to a specific frequency, the front gate to the inner ear is the eardrum - in essence the same thing as a single microphone. Either way, the argument is not relevant because recorded sounds are through a microphone, not millions of microphones tuned to specific frequencies.
Title: Re: In Defense of High Fidelity
Post by: kevin on April 19, 2015, 01:28:32 AM
A friend, who I have great confidence in, did some experiments back in the 80's listening to digitized signal from an analog Master Tape (compared to a direct feed) claimed the point at which he stopped hearing a difference was 400 KHz
The tests were performed over at JPL using experimental DACs, I wasn't there, but I have no reason to believe he lied. He was one of the pioneers of digital audio, but since he is still in the business, and I have not socialized with him in over 20 years, I prefer not to give his name.

Since it's been 20 yrs - are you sure you're remembering correctly? Could he have said 40 kHZ?
Title: Re: In Defense of High Fidelity
Post by: DGCFAD on April 19, 2015, 01:34:28 AM
Well thank god he wasn't one of those

I apologize if I have offended, certainly was not my intent. It is entirely possible he is a member of the AES, I do not know, obviously many audio engineers and designers are members. I was referring to a mindset of "what cannot be measured electronically, does not exist, regardless of the limitations of said measurements and methodology."

In the 80's, members of the AES at their annual convention, would hold blind AB tests to prove to themselves what they already believed, to wit, there is no sonic difference between different audio manufacturers. Only 5% of the listeners (I believe this to be the figure, but I no longer have the article) were able to hear a difference, which they deemed to be statistically insignificant. Peter Moncrieff, (who I assume must also be a member) was able to get a hold of the raw data from one of these tests and discovered something interesting. The 5% that could hear a difference, consistently heard a difference, to the point where some could identify the specific equipment being used. It was upon his findings, and his musings on the nature of human hearing, that I built my early conclusions about the lack of resolution in conventional digital audio (it was a bit later when I met the gentleman who did the sample rate tests, since I already believed that the issue was resolution, that may have enhanced my gullibility, but I tend to take people at face value who have no motive to fabricate).
Title: Re: In Defense of High Fidelity
Post by: Marvey on April 19, 2015, 01:44:26 AM
These things are not difficult to test on your own:
Since equipment can handle different formats slightly differently (internal oversampling, filters, etc.), do the inverse:
I've met a lot of people in the high-end audio business who are full of crap. I will share my own experiences and I will encourage people to discover things on their own.
Title: Re: In Defense of High Fidelity
Post by: Donald North on April 19, 2015, 02:23:08 AM
Here's a link to an article written by my instructor (also a professional pianist) at Caltech where he measured the acoustic spectra of musical instruments to 102kHz:

http://www.cco.caltech.edu/~boyk/spectra/spectra.htm
Title: Re: In Defense of High Fidelity
Post by: DaveBSC on April 19, 2015, 03:48:18 AM
These things are not difficult to test on your own:
  • Start with a high resolution source 24/96, DSD, DXD, etc.
  • Confirm actually hires content (bitrate and frequency) in something like Adobe Audition (some "hires" recordings were found to have no hires content in terms of information above Redbook, in other words, they were fake hires.)
  • Decimate hires content down to various lower resolution formats: 16/44, 20/44, 16/96, etc.
  • Listen to results from DAC capable of playing back these formats on suitably resolving system.
Since equipment can handle different formats slightly differently (internal oversampling, filters, etc.), do the inverse:
  • Start with Redbook 16/44
  • Uprez using good algorithms (such as those in Adobe Audition) to 24/96, 20/44, etc.
  • Listen to results from DAC capable of playing back these formats on suitably resolving system.
I've met a lot of people in the high-end audio business who are full of crap. I will share my own experiences and I will encourage people to discover things on their own.

It's extremely easy to test your ability to hear a difference between Redbook and HD sample rates. AIX records created sample test files using a single 24/96 source file so there would be absolutely NO difference between the files other than sample rates. One is the straight 24/96 file. The other is that same 24/96 file, downsampled to 16/44, and then resampled back to 24/96, so the DAC will see both files as 24/96 and should treat them equally.

http://www.avsforum.com/forum/91-audio-theory-setup-chat/1585994-avs-aix-high-resolution-audio-test-ready-set-go.html
Title: Re: In Defense of High Fidelity
Post by: knerian on April 19, 2015, 05:04:33 AM
Here's a link to an article written by my instructor (also a professional pianist) at Caltech where he measured the acoustic spectra of musical instruments to 102kHz:

http://www.cco.caltech.edu/~boyk/spectra/spectra.htm

Never heard of Boyk before but that is really cool that he is teaching classes in music and engineering/acoustics, just was looking at his site and there are some interesting articles there.  Also had no idea you went to Caltech!
Title: Re: In Defense of High Fidelity
Post by: Anaxilus on April 19, 2015, 05:08:12 AM
Also had no idea you went to Caltech!

It was an online course in ESL.
Title: Re: In Defense of High Fidelity
Post by: knerian on April 19, 2015, 05:29:22 AM
It was an online course in ESL.

I heard Caltech had one of the best ESL programs in the early 90s.
Title: Re: In Defense of High Fidelity
Post by: Solderdude on April 19, 2015, 07:36:06 AM
It was a nice and well written story, though with known truths combined with hear say, non founded beliefs and assumptions based on personal observations.

consider the following:

In the 80's DAC's were in its infancy, analog filters technology with a steep drop-off was just beginning in development/application and had huge amounts of ringing, ripples etc.
They were barely able to make 14 bit DAC's that had like 11 bits ENOB.
Who knows what the guy used and why and where he got the 'tech' from (cutting edge or slapped together with stuff they had) ?

It is not inconceivable that they needed 800kHz (single bit ? ) DAC's and calculated 400kHz or they had low bit amounts of DAC's and had to use 800kHz (or 400kHz ?) sample frequencies to get the noise out of they or needed high sample frequencies so their filters didn't roll-off in the audible band.
Did he actually hear 400kHz or did he hear artefacts (within the audible band) others missed because they didn't 'look' for it ?
Who knows ?

That test data would have been saved if it was that important and articles would have been written about this.
It would have turned thinking (about audibility thresholds) around in those days.
Never seen any reports of this though.

The only loudspeakers that could go near 80kHz were plasma speakers in those days (no mass of diafragms) and piezos (but not at high enough SPL in free air)

It is a nice story ... but would bet my life either numbers are mixed up, remembered wrong or misunderstood.
The eardrum and bones in the ear don't vibrate at 400kHz either.
Only through bone conduction (at high SPL) one could make the hairs 'move' and the question is what these hairs would say.
400kHz or would they say '20kHz' and are just excited by higher frequencies ?

Too many issues to consider the 400kHz a 'reality'  even for a unique individual.



I do share the point about blind tests with larger groups.
even if just one person out of a hundred would actually be able to pick up a difference of something and others couldn't it would be waved away on account of statistics.

Of course there is always a chance someone passes a test by guessing correctly a number of times in a row.

What I would do is single out that person (of interest) and see if he guessed correctly or was able to hear this or that change.
I think every scientist would be very interested in those people, unless they had an agenda to disprove something.
IMO those truly interested in exploring human limits would experiment on that individual as if he was the holy grail.
There would have been papers about this strange individual with abnormal hearing.

Never seen any papers discussing 'rare' individuals that can perform such trickery.

Perhaps we should involve the mythbusters... they did test the brown note and shattering glasses with a voice.


Yes, some people are trained more than others or know what to listen out for.
Musicians don't always make better 'evaluators' certainly when it involves certain aspects they never listen out for.
They might pick out instruments sooner or more accurate than 'your average' person.
Also many sound engineers may not have the best ears/gears around.
I think there are many audiophiles that may hear (somewhat) 'better' than average people but reckon there are more audiophools than audiophiles around.
It probabably has to do with experience.
Can you tell them apart by the posts they make in forums aside from their age ?
I have noticed that the older we get the better the hearing appears to be (more experience with listening ?) but the crappier the ears themselves get.
Interesting aspect ....

There were no analog recordings (tape nor vinyl) that could reach those mentioned frequencies.
If anything even the bias frequency of tape recorders would have been in the 200-400kHz range and any competent tape recorder designer that used a recording head with a single slit would have used a notch filter at the bias frequency for technical reasons.

Vinyl isn't capable of 400kHz. The rotational speed of the lathe platter would have to have been really low to scribe those frequencies into the master (much lower than half speed master).
Aside form that no needle would be able to pick it up (at normal speeds) and would have to have razor thin edges and the cantilever and coils would have to have an extremely low mass and be very rigid.

Fun discussion though, lets see where it leads to.
I am all ears ...







Title: Re: In Defense of High Fidelity
Post by: Anaxilus on April 19, 2015, 08:23:40 AM
Kudos for the Penguin.
Title: Re: In Defense of High Fidelity
Post by: Thad E Ginathom on April 19, 2015, 12:34:18 PM

.

Kudos for the Penguin.

.

Indeed. Impartial common sense approach.

.

I tend to take people at face value who have no motive to fabricate).

.

So do I, but I have learnt that, in audio, or at least, in hifi, one simply cannot.

It is not a case of screaming dirty filthy liar at anybody. There are a few, mostly with a financial interest, that may be (Hello sellers of audiophile ethernet cables and that kind of stuff), and there others who adopt the blinkered world view that suits their business interest, but the vast majority of people are not malicious or unpleasant. Even some of the more extreme forms of audiophoolery might be based in genuine experience, but the 'phools are simply not very good at associating the effect (inside or outside of their heads) with the actual cause. This paper (http://www.sanderssoundsystems.com/technical-white-papers/162-audio-equipment-testing-white-paper) puts that better than I can.

DGCFAD, if you posted that on hydrogen audio, you would be torn to shreds. It might be an interesting experience though: there are guys there who a very well informed about such experiments in the past.

A dose of Hydrogen Audio is a great help in keeping one's feet on the ground. Personally, I feel that one cannot live by hydrogen audio alone. I need the more subjective stuff too --- but then, I describe myself as a recovering audiophile so maybe... one day...  :)p15
Title: Re: In Defense of High Fidelity
Post by: DaveBSC on April 19, 2015, 10:46:57 PM
The only loudspeakers that could go near 80kHz were plasma speakers in those days (no mass of diafragms) and piezos (but not at high enough SPL in free air)

The current king of the hill when it comes to tweeters is Lansche's Corona plasma, which is quoted at 1.5kHz - 150kHz. It's possible that it can go a bit beyond that, with significant roll off. The Murata super tweeter can extend to 100kHz, and will begin to break up at 103kHz. The RAAL tweeters are similarly capable of 100kHz, and they are the absolute state of the art as far as ribbons go. As far as I'm aware, no tweeter has ever been created that can reproduce 200kHz, let alone 400.
Title: Re: In Defense of High Fidelity
Post by: anetode on April 20, 2015, 04:01:18 AM
I apologize if I have offended, certainly was not my intent. It is entirely possible he is a member of the AES, I do not know, obviously many audio engineers and designers are members. I was referring to a mindset of "what cannot be measured electronically, does not exist, regardless of the limitations of said measurements and methodology."

It certainly wasn't your manner which was offensive, rather the technical merits of your argument. I don't have the penguin's considerate nature to address each concerning aspect, so instead I'd like to point you to a writeup from some time back which addresses the premise of your argument - http://www.changstar.com/index.php/topic,1624.0.html
Title: Re: In Defense of High Fidelity
Post by: Chris F on April 20, 2015, 04:21:31 PM
Regarding vinyl response and noise:

The frequency response of my needledrops (usnig a Lyra Kleos cartridge) extends to 50Khz+.   The noise floor (between tracks) is typically -50 to -55dB after normalization.  With a better turntable (I have a VPI Classic 1) and isolation I think this could be improved but it's a ballpark number.

Edit: Corrected the noise floor number.  I wish I could get a noise floor of -70 to -75dB on normalized vinyl rips!

Title: Re: In Defense of High Fidelity
Post by: Solderdude on April 20, 2015, 06:50:57 PM
Still a long way removed from the claimed 400kHz though ....
The cutting lathe used for vinyl mastering usually was filtered at 50 kHz with a gentle low-pass filter.

Nice cart and deck though.

(http://img842.imageshack.us/img842/4461/mantheyporsche997gt3rsr.jpg)