Microphony III
- Thread starter BE718
- Start date
Purité Audio
Trade: Purite Audio
Alan Hi, I can ask Alvin at GPA,their stands use Sorbathane pads, of the correct height and durometer for the mass of the load to be isolated.
We measured one here, when we were comparing active isolation tables, it did pretty well in the vertical plane, actually measured better than an active table( loudspeaker type)
Keith.
I expect they will be the exception and be happy to provide data because they know their product is based on science and not foo!
I'm fascinated, they are demonstrating phase coherence in cables, is that correct?
Purité Audio
Trade: Purite Audio
A very nice chap from Accurion UK, came here with his measuring kit and his active table, I have posted some photographs way back I this thread.
He used three accelerometers which measured in the vertical and lateral planes.
We measured the floor and the GPA stand and compared to the active table.
The vertical plots for the visco elastic and active were almost identical, neither did terribly well laterally.
Effective isolation does not have to be expensive, it just needs the application of proper engineering.
Keith.
Purité Audio
Trade: Purite Audio
Tony L
Administrator
You need to put yourself in my position. It is not my role to censor threads in order to protect MusicWorks, Russ Andrews or whoever's businesses. If someone queries the logic behind say a "phase coherence dem" then why should I have to gag that question? It it perfectly fair thing to ask IMHO. As long as things don't drop too far into childish name-calling (e.g. "measurists", "foo merchants" etc) and stay focused on trying to logically assess claims being made then I'm perfectly happy to run it. This has been a good thread IMO. I have no issue at all in pfm members putting marketing claims about microphony cures etc to the test and publishing their findings.
One of my main disappointments with modern audio is the degree of rigour, scientific logic and willingness to repeatedly test and publish findings/white papers I find when reading up on the true audio pioneers (Peter Walker, PWK, Gilbert Briggs, JE Sugden, BBC etc etc) seems almost entirely missing in action. Any small thing pfm can do to help redress that balance and try to get people really thinking about the mechanisms in play is a good thing IMO. I'm not looking for any kind of 'witch hunt' here at all, only a culture where claims may be politely put to the test.
PS I freely admit some of this thread falls below the standard I seek, I've been too busy to moderate as hard as I'd like, though it has to be said most of the abuse and name calling seems to have been directed at those taking the time and effort to do some real investigative journalism. I've little time for defensive fanboy stances, ideally one should arrive at any intelligent discussion with evidence and a coherent theory that is of a standard that it may be tested.
Werner
pfm Member
Allow me to be pedantic.
A paper is a scientific publication, and expected by the scientific community to be of a certain minimum standard.
A white paper is a fancy name for a marketing leaflet, its contents entirely uncontrolled.
Tony L
Administrator
Ok, let's call them 'papers'. I'm pretty sure all those I list meet that requirement, e.g. the countless publications about horn design by Paul Klipsch, JE Sugden publishing the full circuit of the original A21 in his HI-Fi News magazine article on class A amplifier design, the BBC research papers into thin-wall cabinet design, Gilbert Briggs writing many (superb) books on loudspeakers etc etc.
Well, its actually quite easy to measure the phase change across a cable. Do it with a scope.
Mind you I cant imagine just how bad a cable would need to be to create enough of a filter at audio frequencies to impact the phase of the signal.
Steven Toy
Accuphase newbie
I think BE and I have reached some kind of acknowledgement of common ground along the lines that the ReVo may have an effect but we know not of its causal mechanism.
I think Keith may be using this thread to score points against a competitor. He certainly has an interest going beyond that of a mere fanboy.
I think Keith may be using this thread to score points against a competitor. He certainly has an interest going beyond that of a mere fanboy.
Steven Toy
Accuphase newbie
FWIW, with the exception of a digital coax cable I don't use cables sold by MusicWorks. I use Mark Grant cables + the Sterling Black Mamba speaker cable of unknown origin that was cheap enough back in 2008 not to be classed as 'foo.'
In any case, this is the microphony/equipment support thread not the lets-bash-an-established-and-reputable-business thread.
I use AudioWorks in part because I like what their supports do sonically, whatever it is they may actually do, but also for their exemplary customer service.
.mmmm.....well.........eeerrrmmmm....OK, I wont argue with the first statement at the moment just for the sake of peace and harmony on pink fish.
Regarding your second point, I'm afraid the notion of a short interconnect cable affecting the phase of signals is another incredible claim. Keith is correct to be somewhat incredulous.
I am happy to measure the hase difference between the output of say the mdac and input of the TAG amp. Its actually very easy to do.
In the meantime I realised I have a chunk of perspex we can test for vibration isolation. I totally forgot about my headphone stand. I can place the MDAC on it (stand on its side) and measure vibration transfer.
whatsnext
Naimless
BE718 the wonder stands are made of Acrylic not perspex and a special version at that no doubt.
Exploring the potential SQ benefits of Acrylic sheet a few years back as a result of Stevens joy at Musicworks stuff I found it made no difference in my system - that was 15mm clear.
It is pretty dead to vibration though, tap test. The sheet I tried is still in place in case it burned in
Exploring the potential SQ benefits of Acrylic sheet a few years back as a result of Stevens joy at Musicworks stuff I found it made no difference in my system - that was 15mm clear.
It is pretty dead to vibration though, tap test. The sheet I tried is still in place in case it burned in
I was under the impression they are the same thing....or have I just had a sarcasm bypass?
Burned in
whatsnext
Naimless
I was under the impression they are the same thing....or have I just had a sarcasm bypass?
Burned in
I am not a chemist but the Acrylic I sourced seemed denser and less shiny transparent that the lighter perspex I have encountered in the past.
Having said that Perspex is a trade name for a form of Acrylic
adamdea
You are not a sound quality evaluation device
Don't worry. I'm quite sure that no one else thinks that..mmmm.....well.........eeerrrmmmm....OK, I wont argue with the first statement at the moment just for the sake of peace and harmony on pink fish.
ultrawomble
Sith Lord
It may have been leaded acrylic - used to have a lot of it in the lab back in the day when using 32P labelled nucleotides.