music fiend
life lusting
The latter. And you?
Microphony III
- Thread starter BE718
- Start date
The latter. And you?
It's the 2011 pdf - is that the one you looked at? Hav'nt a clue if it's been peer reviewed or progressed further.
Which bits were not clear?
Cheers. Bill
cooky1257
pfm Member
The source file is ripped into the pc without any of these accessories and yet they then burn a cdr to check the effects of ...of all it proves to me is listen via a bog standard PC...I don't get how the errors aren't just via the adc/dac/analogue processing that's going on-could they be encrypted into the cdr......something isn't right but I lack the digital nouse to figure it out.
Hmmmmmm, I guess it depends how these 'clearly demonstrable improvements' are tested.
The only properly conducted tests I've seen have not demonstrated this.
http://www.bostonaudiosociety.org/bas_speaker/abx_testing2.htm
http://matrixhifi.com/ENG_contenedor_ppec.htm
The test is extremely flawed. As Werner said earlier, did they not understand why it's technically flawed or were they just hoping they could blag people?
Either way it's an indictment regarding some of the players in this industry.
Werner covered some of the flaws in the hydrogen audio link. I have no intention discussing further in this thread. Don't really want it to get dragged off topic.
Hopefully going to test some acrylic/ Perspex today.
Do please expand on your thoughts - I assume you're referring to the later Vertex paper.
Cheers. Bill
As I said Read werners comments on the hydrogen forum link. We dont need to rehash it here. Its a flawed methodology. One thing I will point out, which i dont think has been elsewhere, is that measuring the outputs with speakers connected is a bit dumb. The speakers produce back EMFs which will effect the signal. They also act like microphones, again producing voltages. I'll post some plots of just this happening.
Perhaps I might move on to some time domain testing after this.
Werner
pfm Member
Yes, we've read the later blurbs. If anything, they made their pit deeper. The really last thing they wrote on the subject is on the website:
At the height of this collaboration, during 2010 and 2011, presentations on this subject were given at audio shows both in the UK and in the US, and whilst this generated a good level of interest in this work, it didnt produce a source of revenue to fund this work. And so, for a while, both Steve and Gareth had to back away from this work in order to focus on activities within Vertex AQ and Acuity Products that generated income into their individual companies.
But 2014 could be just the year to start to move things forward once again??
If you're really interested read back all that was posted on the various serious audio forums in the relevant period and try to understand it. It's all in there, really no need to rehash it here. Let it rest.
At least until the clowns re-emerge for an encore.
There isnt per se, there have been a couple of brief summaries. I will try and get round to doing it
Its funny, because you would have thought that proper R&D that produced accurate and credible scientific findings that proved their products worked (and why) would have been in their companies interest...............
The test may be flawed - I don't know. However they were presenting information to laymen, not scientists, so there has to be some dumming down.
Certainly one could argue that for scientific rigour they could present their papers to the AES. Why they haven't I can't say.
The Hydrogenaudio thread was mainly smug people just laughing, only the last post by Werner having some substance but that is mostly guess work.
It is of interest to us because they are discussing exactly the sort of things we are discussing on this thread. They are claiming to have made measurements that show changes in microphony.
It is also the sort of thing some people on here are crying out for - measurements to show an effect that may be audible. When such an attempt arrives they are dismissed in one or two sweeping statements.
music fiend
life lusting
As they used the same method with and without the accessories whatever is introduced by adc/ dac/ analoge is present in both cases.
Then they simply compare the errors with and without the accessories.
Why do you say something isn't right?
Purité Audio
Trade: Purite Audio
Hip, if my understanding of their procedure is correct , they simply weren't measuring the same thing, they had an unreconstructed WAV file as their reference, and they were comparing it to a file which had been passed through a DAC and then an ADC.
I am not sure why they simply did not compare two identical files, measured at the output,one with their power cable /stand ,the way Alan has.
Keith.
I am not sure why they simply did not compare two identical files, measured at the output,one with their power cable /stand ,the way Alan has.
Keith.
music fiend
life lusting
It's quite amusing really.
Some here are quick to praise measurements that do not show differences using accessories.
However if there are measurements that show differences using accessories the same are quick to dismiss these saying the tests are flawed.
As this also deals with microphony I think it would be interesting to discuss it in a thread named Microphony III.
music fiend
life lusting
Please read my post #554.
I wasnt aware of these tests until werner provided the links. I hadnt got hardly any way into the text before I started saying "thats a problem....that wont work.........why are they doing that..........."
Anyone with a bit of technical knowledge will quickly pull the test apart, the problem is they are selling to laymen. Thats probably why the forum came across as smug to you, because people that have a bit of technical knowledge can barely believe what was happening.
In fact they seem to have constructed the test in a way that will make it impossible to perform the error difference result they want. So they are either technically incompetent, or bullshitters trying to blag people......dont forget they have a vested interest.
Just as a hint, why are they using a raw wave file to compare to one that has been replayed by a CD player and then re-digitised by a PC sound card?
Arent they concerned about the fact that the CD will have output filtering? Arent they concerned that the sound card will have input filtering?
Why are they using a sound card, clearly not a professional piece of instrumentation? A PC is a hostile place for sensitive instrumentation. Whats its noise performance? Whats its spuria look like? How is the output of the CD playing affecting the input of the sound card?
We have seen in my measurements the differences in noise output from the MDAC with its different filters. We have seen how (presumably) out of band noise from the MDAC affects my TAG analogue and digitised analogue inputs.
If all the respective word clocks arent synced you are going to get differences every time.
.....and so on...and so on.......
But as werner has said, this has all been ripped apart elsewhere, there is no need to re-hash here.
adamdea
You are not a sound quality evaluation device
I suggest that you read the extensive threads discussing it- Werner posted the links.
Iirc one of the many flaws in the experiment was that they tried to prove their conclusion using a "measurement" which was dimensionally meaningless - a sort of diagonal where x and y where in unrelated dimensions (the result would change depending on how you chose the units). I seem to remember SQ
posting on that point.
But it's years ago, memory is dim, there were many flaws, and it was all extensively debated at the time.
That is not what has happened, it has been technically explained why the measurements were flawed.
I am happy to take on board any questioning if you think the measurements in this thread are flawed.