MQA discussion
- Thread starter asiufy
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Not true, I can (and have done quite a bit) listen to the Tidal "software unfolding", although I don't claim that gives me the full benefit. OTOH, I don't think the Dragonfly really gives one more than an inkling either; when I borrowed one to compare with my Oppo, partial unfolding through the Oppo usually sounded better.
In either case, that has nothing to do with designing and implementing a true test for MQA's audio benefits, whatever they might be.
Aren't you actually agreeing ?
M says it sounds better thane RB
RBB says well if it doesn't something must be wrong ?
It seems that the complexity of what MQA is confusing people expectations
We are coming from a audiophile hi rez perspective
For us,
correction of adc "sins" of the past
master authenticated hi rez should be our interest
i think much of the comments are at cross purposes to Wbf
The September 2017 TAS Essay on MQA
I think everyone ought to read Harley's essay on MQA and recent research on human hearing, in the September issue. More than the claim that MQA is a paradigm shift, for me the more important parts were those about the ear, with medical research allegedly showing that it is not the passive device we always thought it was, but an active one, with additional neural pathways from the brain to it, which steer it to focus on the location and direction of sounds, plus make it sensitive to temporal aspects of sounds we hear. (Frankly, isn't this how our brain and eyes fundamentally also work?) This on top of references in the January issue's essay by Roger Skoff, which claims that the ear can perceive sounds far beyond 20kHz. The great thing about the September essay is that there are specific scientific references.
I think TAS should put that essay on their site.
I think everyone ought to read Harley's essay on MQA and recent research on human hearing, in the September issue. More than the claim that MQA is a paradigm shift, for me the more important parts were those about the ear, with medical research allegedly showing that it is not the passive device we always thought it was, but an active one, with additional neural pathways from the brain to it, which steer it to focus on the location and direction of sounds, plus make it sensitive to temporal aspects of sounds we hear. (Frankly, isn't this how our brain and eyes fundamentally also work?) This on top of references in the January issue's essay by Roger Skoff, which claims that the ear can perceive sounds far beyond 20kHz. The great thing about the September essay is that there are specific scientific references.
I think TAS should put that essay on their site.
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We are coming from a audiophile hi rez perspective
For us,
correction of adc "sins" of the past
master authenticated hi rez should be our interest
i think much of the comments are at cross purposes to Wbf
IMHO correction of ADC "sins" is the real aspect that can interest an audiophile, in case he wants to listen to old recordings. As far as I understand, the MQA implementations are carried in firmware, and use the existing DAC chips. MQA just processes the digital data flowing in the machine. This means that they can not surpass the limitations of the internal circuits, working most of the time at DXD rates. My question is still : if we could play MQA processed DXD files in our DACs they would sound different from common MQA?
Given Harley's track record, it is unwise to pay any attention to what he writes. I haven't read Skoff's essay, but there is no scientific evidence whatsoever that the ear itself can perceive anything beyond the upper limit of an individual's hair cells, none of which go beyond 20 kHz except in a small (<1%) number of young (under 30 yrs old) people, and the upper limit is much lower as people age. There are theories about the paranasal sinuses changing the perceived frequency of some ultrasonic signals allowing them to trigger hair cells that respond to lower frequencies, but they are only theories. There are other theories with somewhat more persuasive evidence that other parts of the body may perceive some ultrasonic signals, but that is not the same as hearing them.
Deezer jumps onboard:
https://positive-feedback.com/industry-news/mqa-strikes-global-agreement-deezer/
https://positive-feedback.com/industry-news/mqa-strikes-global-agreement-deezer/
Well said, rrbert. While at best there may be the sporadic scientific article once every few years that claims sound perception above 20 kHz, all this amounts to nothing but anecdotes. The scientific consensus is that there is no hearing above 20 kHz. And yes, just any perception is not the same as hearing. Claiming that science is on one's side just because of one sporadic publication here and there is a stretch.
Several of the machines such as Berkeley have required another board
Possibly those with fpga may be able to do it in firmware
I suppose it may be easier and keep both companies IP to just add a board
I agree that at best reports of perception at greater than 20khz into ultra frequencies is very limited
Some interesting reports of whole brain and eyeball resonances able to detect ultra frequency
Be that as it may , it won't be a "pitch" related perception
However the issue about reproducing ultrafrequencies has nothing to do with hearing it, but rather two issues
1. Timing, or more exactly time domain issues
2. Getting above the Nyquist limit of a band limited frequency output, without doing it artificially and producing aliasing which you then need to put a filter in place to try and eliminate it, which has in the past produced further issues
The frequency domain is the other side of the coin of time domain
As an aside
There appears to be experimental evidence that the cochlea can respond to ultrasound through bone conduction
The air borne system is mechanically limited to 20-24khz
I just read a thesis that seems to to confirm the work of Nishimura about ultrasounic masking via bone conduction using distortion product otoacoustic emissions
Though the basement membrane normally is thought to not respond to above 20khz, it seems likely there is demodulation of the ultrasonic frequencies into the upper high frequency hearing with a peak response at about 13khz
This would allow perception and even the possibility of some pitch discrimination
Very fascinating.... though applicability to other than headphone or underwater listeners seems limited
There appears to be experimental evidence that the cochlea can respond to ultrasound through bone conduction
The air borne system is mechanically limited to 20-24khz
I just read a thesis that seems to to confirm the work of Nishimura about ultrasounic masking via bone conduction using distortion product otoacoustic emissions
Though the basement membrane normally is thought to not respond to above 20khz, it seems likely there is demodulation of the ultrasonic frequencies into the upper high frequency hearing with a peak response at about 13khz
This would allow perception and even the possibility of some pitch discrimination
Very fascinating
.... though applicability to other than headphone or underwater listeners seems limited
There is research that dates back to the 50's, apparently claiming bone conduction up to 150kHz in some young humans. See https://biology.stackexchange.com/questions/27898/can-humans-perceive-sounds-above-20-khz which is referencing a paper in Nature, but I don't want to spend $199 to read it. Specifically it says:
There are other similar papers on bone conduction and the upper limits of human perception, if anyone here cares to search. I would also suggest reading Harley's cited medical links in the September essay I mentioned, which shed light on those brain-to-ear pathways discovered.
The thing is, in 1950 there was no way to measure brain-stem evoked potentials (only became practical to do so in the late '60's), so the type of methodology required just wasn't possible.
Ear-brain pathways won't affect ultrasonic hearing (which is what I thought was being discussed). Again, paying attention to anything Harley says or writes, particularly in the scientific arena, is foolish; he has no scientific qualifications, and in the past has made too many egregiously incorrect statememts to keep track of.
Ear-brain pathways won't affect ultrasonic hearing (which is what I thought was being discussed). Again, paying attention to anything Harley says or writes, particularly in the scientific arena, is foolish; he has no scientific qualifications, and in the past has made too many egregiously incorrect statememts to keep track of.
It's possible Nature published nonsense, but Nature is known as one of the toughest more prestigious publications, wouldn't you say?
Nope, two different things - I mentioned earlier the alleged connection of those pathways to brain focus and sensitivity to temporal aspects of sounds. I am simply trying to get people to read up on research on the ear, and get past the ordinary readings in most audio e/magazines.
If you read it, it should be obvious that this is all coming from Meridian, through his magazine.
So he is still shilling for Meridian ?
No matter how rigorous Nature is (and that has varied tremendously over the years, it's not so great today, no idea what it was in 1950), the editors and reviewers can only judge by the standards of the time.
All the senses can be "trained". Far and away, the most research in humans has been done with sight (no surprise), but touch, taste and hearing are increasingly trained as well. Smell, not so much except when it is combined with taste. In dogs, though...
?No matter how rigorous Nature is (and that has varied tremendously over the years, it's not so great today, no idea what it was in 1950), the editors and reviewers can only judge by the standards of the time.
All the senses can be "trained". Far and away, the most research in humans has been done with sight (no surprise), but touch, taste and hearing are increasingly trained as well. Smell, not so much except when it is combined with taste. In dogs, though...
There has not been a great deal of work in this area is true
DPOCE is interesting as it a non invasive way to see what the hair cells are responding to
As this also fits with previous experiments its a good fit for the current model that the cochlea does respond to ultrasonics thru bone conduction
i am not saying it relevant to normal listening .....
Nature remains one of the most cited journals in science with IF of 40
Most scientist remain delighted to get accepted into Nature, though there are more alternatives now
over the years a few Nobel laureates seem to have published there....might mean something ?
DPOCE is interesting as it a non invasive way to see what the hair cells are responding to
As this also fits with previous experiments its a good fit for the current model that the cochlea does respond to ultrasonics thru bone conduction
i am not saying it relevant to normal listening .....
Nature remains one of the most cited journals in science with IF of 40
Most scientist remain delighted to get accepted into Nature, though there are more alternatives now
over the years a few Nobel laureates seem to have published there
....might mean something ?Yes, Nature is top notch. And of course, bone conduction has nothing to do with normal hearing.
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