Topic: In Defense of High Fidelity (Read 2354 times)

Anaxilus · « **Reply #10 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:

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.

Marvey · « **Reply #11 on:** April 19, 2015, 12:21:41 AM »

Quote from: DGCFAD on April 18, 2015, 06:39:56 PM

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.

kevin · « **Reply #12 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?

DGCFAD · « **Reply #13 on:** April 19, 2015, 01:34:28 AM »

Quote from: anetode on April 18, 2015, 11:56:12 PM

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).

Marvey · « **Reply #14 on:** April 19, 2015, 01:44:26 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.

Donald North · « **Reply #15 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

DaveBSC · « **Reply #16 on:** April 19, 2015, 03:48:18 AM »

Quote from: purr1n on April 19, 2015, 01:44:26 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

knerian · « **Reply #17 on:** April 19, 2015, 05:04:33 AM »

Quote from: 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

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!

Anaxilus · « **Reply #18 on:** April 19, 2015, 05:08:12 AM »

Quote from: knerian on April 19, 2015, 05:04:33 AM

Also had no idea you went to Caltech!

It was an online course in ESL.

knerian · « **Reply #19 on:** April 19, 2015, 05:29:22 AM »

Quote from: Anaxilus on April 19, 2015, 05:08:12 AM

It was an online course in ESL.

I heard Caltech had one of the best ESL programs in the early 90s.

Author Topic: In Defense of High Fidelity (Read 2354 times)

Anaxilus

Re: In Defense of High Fidelity

Marvey

Re: In Defense of High Fidelity

kevin

Re: In Defense of High Fidelity

DGCFAD

Re: In Defense of High Fidelity

Marvey

Re: In Defense of High Fidelity

Donald North

Re: In Defense of High Fidelity

DaveBSC

Re: In Defense of High Fidelity

knerian

Re: In Defense of High Fidelity

Anaxilus

Re: In Defense of High Fidelity

knerian

Re: In Defense of High Fidelity

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Author Topic: In Defense of High Fidelity (Read 2354 times)