moosemeat
pfm Member
Hi John,
In light of this debate, this site may be of interest: http://www.ayre.com/insights_dsdvspcm.htm
DSD & PCM files recorded with the same equipment available for comparison.
Cheers,
Bruce
MDAC First Listen (part 00100011)
- Thread starter highfi
- Start date
- Status
Hi John,
In light of this debate, this site may be of interest: http://www.ayre.com/insights_dsdvspcm.htm
DSD & PCM files recorded with the same equipment available for comparison.
Cheers,
Bruce
adamdea
You are not a sound quality evaluation device
I have been waiting for Ayre to publish the results of this test. I don't know whether they have not had enough response, not got the results they wanted, or just lost interest. Whichever it is, they have not yet
"put to rest many of the myths that Sony created around DSD when they first were trying to recapture the revenues lost by the expiring CD patent"
moosemeat
pfm Member
Yes, there's no doubt Ayre are not proponents of DSD.
adamdea
You are not a sound quality evaluation device
Sort of- it actually isn't obviously part of experiencing sound, although it might seem obvious: the problem is that IIRC the mysterious brain effect did not match an actual preference/detection.
Plus interestingly the follow up showed that this mysterious effect did not work with headphones.
adamdea
You are not a sound quality evaluation device
Intriguing- but give us the answer, Mr Hansen.
JohnW
pfm member
Bruce,
I've seen this link before - the problem is:-
"When switching between recording DSD or PCM, all of the internal hardware is identical. All of the analog circuitry, power supplies, digital circuitry, converter chips, PCB material , et cetera is 100% identical. The only difference in the algorithms used to process the raw data from the Arda AT1201 ADC chip (6 bits at 256 Fs) either into DSD or into PCM. "
The Arda AT1201 ADC chip is 6 bits at 256 Fs, so its not a pure DSD ADC, the data has to be filtered and remodulated to generate a "1Bit Stream" = DSD
Ayre MUST be aware of this (they go so far as to mention it on there Webpage) so this is NOT a pure DSD verse PCM test - it only adds to the confusion and a total waste of time. SHAME on them, they should know better!
The Arda ADC has its issues with idle tones in the ADC modulator (despite it being 6Bits) - this is a sure indicator of poor design.
MDAC2 L3 (when its completed!) for better or worst implements a true 1Bit ADC - so can output a "Pure" DSD Bitstream.
Well, infinite amount of "dots" doesn't make a curve, it only "approaches" it.
My take on all this is that people often pick one concept and then (perhaps incorrectly) generalize it.
This takes a relatively simple concept presented by Nyquist and Shannon and goes on to imply something, which isn't transitive through it. There are so many related things, filters for example (my personal guess is impulse response), quantization error alteration (dither), encoding (PCM), limited resolution (16bit), ..., all of which can indirectly affect the result.
None of which break the theorem or somehow "prove" that their effect is audible. If anything, they prove that the result is just an approximation of the original (well, what isn't
).Come on, don't let this thread sink into the same black hole like the others, create a new one if you're interested in the discussion. People here just track the news about MDAC2.
misterdog
Not the canine kind
Not necessarily.
I always find it illuminating to hear Johns views and aims, it reaffirms that we are following the shepherd and not the sheep.
Ians comments led to some interesting posts IMO.
Besides news about MDAC 2 can be slow sometimes
JohnW
pfm member
This is not really an MDAC2 thread but all things MDAC and related
Basically, a friendly place for MDAC owners to meet and discuss "almost" related subjects
This is what I'm hoping for. Like it or not, most of the music I want to listen to has already been recorded in pcm, at 44.1k
()And if I want to actively make use of DSP, then I can't really do it on a DSD recording
Whatever transpires, I look forward with interest to what results
Sure, great, I just wouldn't want to dig through 20 pages / day of ego fight, that's all.This is not really an MDAC2 thread but all things MDAC and related
Basically, a friendly place for MDAC owners to meet and discuss "almost" related subjects
Unless John/Dominik get into 1-bit DSD processing.
moosemeat
pfm Member
Hi John,
That's interesting... they certainly came across as having a biased point of view.
By sharing the link, I was not trying to make a case either way; I am not in a position to judge. I just thought that the samples could be useful to allow people to draw their own conclusions. But if they are not both valid samples, then they do not serve that purpose.
Cheers,
Bruce
iansr
pfm Member
A few years ago a radio DJ played the same piece of music twice, once from an LP and once from CD. He took care to pick an LP without pops and crackles and fade up the track just as the music started. He didn't say which was which but asked people to subsequently phone in and say which version they preferred. I don't recall the precise percentage but a significantly ( as in statistically significant) greater proportion of callers preferred the LP. And this was over an FM radio.
Now OK, this wasn't scientific and not doubt critics would say that perhaps he subconsciously gave some clues as to which was which etc etc, but I think it would be a mistake to dismiss this event out of hand.
Now OK, this wasn't scientific and not doubt critics would say that perhaps he subconsciously gave some clues as to which was which etc etc, but I think it would be a mistake to dismiss this event out of hand.
Julf
Facts are our friends
I guess it only proves that the pleasant colouring and distortion of vinyl survives even a FM chain (that probably includes digital components).
A much more interesting test would be to take a digitally recorded original recording, and engrave it on vinyl without any vinyl-specific equalisation, and then compare the vinyl record to the digital recording.
I've been trying to work out if the comparison really lets us compare DSD and PCM as the replay process is PCM. Ultimately, somewhere in the chain is a DSD -> PCM conversion
iansr
pfm Member
Julf
The advocates of vinyl often say it sounds more "musical" than CD. If that is due to distortion then fine. I listen to music for pleasure and if the alleged distortion increases my pleasure then gimme that distortion. This is rather like what some people say about valve amplifiers; they sound good because they are introducing some sonic artefacts that actually make the music sound better. I personally think there is something unique and special about the way a well implemented SET amp sounds. The reason I'm on the list for the VFET amp is that VFETS behave like triodes, but you don't have to use a pesky output transformer AND with John's design you get a shed load of watts.
The advocates of vinyl often say it sounds more "musical" than CD. If that is due to distortion then fine. I listen to music for pleasure and if the alleged distortion increases my pleasure then gimme that distortion. This is rather like what some people say about valve amplifiers; they sound good because they are introducing some sonic artefacts that actually make the music sound better. I personally think there is something unique and special about the way a well implemented SET amp sounds. The reason I'm on the list for the VFET amp is that VFETS behave like triodes, but you don't have to use a pesky output transformer AND with John's design you get a shed load of watts.
moosemeat
pfm Member
Well said.
Julf
Facts are our friends
adamdea
You are not a sound quality evaluation device
I was under the impression that most (all?) of them are sigma delta nowadays so I'm not sure the analog Anti Aliasing filter is much of an issue-most of the heavy lifting is done by a digital filter when the A/D output is decimated to PCM.
Does anyone know whether they have an analog AA filter at all, or do they rely on the mic's natural roll off? For the m-dac 2 operating at 14Mhz you would only need to cut out signals over 7MHz.
Are there any multibit A/Ds these days?
- Status