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[Barry Hufker]

Markus,

Again I can agree with all you say.

Michael, I find your comment about the top quite interesting.  That is one of the things I'll file away for later use.

Barry

[Kees de Visser]

Klaus Heyne wrote on Tue, 26 June 2007 06:18

To my knowledge, there is no standardized double blind or any other type of listening test that is universally accepted by the professional audio community at this time.

Well, there is the "AES Technical Committee: Perception and Subjective Evaluation of Audio" http://www.aes.org/technical/pseas/ but I'm not sure if they are getting/seeking enough publicity and recognition.

Quote:

Few "professionals" have invested time and energy into their own hearing education, and consequently are unsure of what they hear, and how to file in their brain what they heard. Many of them would not risk being exposed as tin ears and amateurs, possibly ruining their reputation and source of income.

IMO that's spot on. It makes it difficult to find "golden" ears for time consuming listening tests.

Quote:

I will continue to defy those who are unwilling to first and foremost use their ears to judge audio. But I will also continue to stress to improve our perceptions, and start to work towards a universal language and protocol of evaluation that is broadly agreeable.

Glad to hear. What universal language do you have in mind ?

[Barry Hufker]

Esperanto.

[Kees de Visser]

maarvold wrote on Wed, 27 June 2007 03:05

It seems like one potentially valuable 'analog' source for double blind A/B/X testing might be a piano equipped with Yamaha's Disklavier recording/playback system.

Interesting idea. I remember that once for a comparative microphone test during a Tonmeister Tagung a computer controlled B

[Schallfeldnebel]

Kees de Visser wrote on Thu, 28 June 2007 06:30

Any other ideas for a reproducable source ?

Yes,  a very simple way. You take a line signal from an analog or digital tape recorder, which you attenuate to microphone level, and boost to line level again by using your favourite mike-preamp.

This gives a very reliable source, and the output level can be varied. It is interesting to hear that the higher the output level is, the less sensitive is the cable. Those cables which were on microphone level not that good, sounded much better on line level.

The only thing which is hard to test the way I suggested is the influence of phantom powering.

Erik Sikkema

Schallfeldwebel

[maxdimario]

the way that the mic cable will 'work' is influenced by the type of driver circuit and load.

so depending on if it's a transformer mic or not and if the mic pre has a transformer etc. etc. you will get different results.

to test cables I would suggest using an unusually high source impedance, as this is probably the best way to hear the defects.

[Kees de Visser]

Schallfeldwebel wrote on Thu, 28 June 2007 02:08

Kees de Visser wrote on Thu, 28 June 2007 06:30  Any other ideas for a reproducable source ? Yes,  a very simple way. You take a line signal from an analog or digital tape recorder, which you attenuate to microphone level, and boost to line level again by using your favourite mike-preamp.

My mistake. I meant to say: "Any other ideas for a reproducible acoustical source (in front of the microphone) ?"
Mechanical instruments come to mind, like the automated B

[Schallfeldnebel]

Probably a pipeorgan would be a good source, since it's sound is complex; you can get everything from about 16Hz up to 20K-25K, and it is often stable standing and fixed to one place. If you keep an eye on the temperature of the room, the tuning stays mostly stable too. Some of them here in Europe are standing or hanging for more than 400 years in the same venue.

Most of the time my testing instrument was the organ, and I have been lucky to work with great players like Harald Vogel and Jacques van Oortmerssen, who have such a good touche on the keyboard, that the sound they produce is equal to the ear.

Organs with electro pneumatic action have no different sound caused by a different touche, those might be even better test objects.

Schallfeldwebel

[Klaus Heyne]

Any testing method that deviates from the actual application- in this case, plugging a condenser mic into a cable, and plugging that cable into a mic pre- suffers from credibility problems.

There is only one, very rare, and probably unobtainable, player piano machine which can express the dynamic and analog behavior of a real piano played by hand. All others are so far away from simulating what a real piano sounds like that test results would be unreliable.

Furthermore Erik's idea of using a pre-recorded sound source suffers from the uncertainty of what really happens electrically during the impedance up- impedance down conversion that's necessary in simulating the impedance behavior of a real mic/preamp interaction.

If that issue could be solved, then the much larger issue of: "what does the mic really sound like"? and therefore: "what are the cable's imprints on the sound of the mic?" could be answered.

But that is not ever how we generally approach music recording, or is it? A good engineer never chooses supposedly neutral components for recording. The vast variations in microphone performance alone attest to the creative choices the engineer/performer/producer must make to bring out the music in the way he/she intends for the recording. That choice extends to the cables used as well.

Except, that, in my experience, there aren't any good, clear choices available (yet!), only more or less unsatisfying compromises.

Unlike the audiophile/HiFi (line level) cable world, cable design for microphone is still in its infancy. Here, the handfull of makers compete mainly on hype, endorsements and price, rather than catering to and satisfying a sophisticated clientele. That clientele does not yet exist in large enough numbers to make a difference in choices and quality of the products that are available.

[Barry Hufker]

Here's the latest from me.

I used a Telefunken-USA U-47M (with VF14 tube and K47 capsule) for a test involving spoken word only.  The setup was otherwise the same as previously posted: microphone (its cable to power supply) to TEST CABLE to Gordon Instruments preamp to generic cable to RADAR 24.  The recording again at 24/96.  The result was a greater disparity than before.  The GAC-2 cable from Gotham was etched and thin, while the Accusound wire was smooth and full.  Quite frankly it is the only cable of those two to use.  The mic sounded "fine" or "OK" with Gotham but sounded warm and rich with Accusound.

Frequency sweep: taking advice posted here, I made two consecutive frequency sweeps through the U-47M.  Interestingly, the Accusound cable showed significant differences from one sweep to another although nothing bizarre, just noticeably different.  On the other hand, the Gotham cable's traces -- both of them -- were exactly the same.

Barry

[maxdimario]

could be the transformer output of the u47 which makes the marked difference..

could also be that the u47 has more there to begin with and the 'good' cable is letting it shine for what it is, as opposed to masking it.

a more complex fet mic might have less clarity to shine through so the difference between cables may also be less noticeable..

[Klaus Heyne]

Barry,
You continue to compare the same two cables with different mics/pres/settings.
This could lead readers to the impression that one of them is bad, the other one good, at least as far as your subjective reporting so far is concerned.

The impression you create is that the Accusound is a good cable, and the GAC2 not so good (the latter of which I agree with, from my past testing.)

Before anyone goes running out and buys the Accusound, it could very well be that, in a different, expanded comparison test, the GAC2 ends up being pretty lousy, and the Accu a bit less lousy. Or, that indeed the Accusound may be the new gold standard.

[Barry Hufker]

Klaus,

I take your point but I don't think you've stated the case correctly.

1. Like any "good" scientist, I changed only one variable: I added only a new microphone this time.  Everything else was as before -- same preamp, same generic cable between preamp and recorder (which is all I can get) and the same recorder.  Same gain settings, same room, same "me", same recording rate and bit depth.  The only thing that changed this time was the microphone.  By changing the microphone (only) I have demonstrated this sonic change is not relegated to only one microphone or microphone type.  The effect may indeed be related to the cables themselves.  That should explain this part of the most recent test.

2. As was suggested from one of the posts here, I made two tone sweeps (20-20k) this time for each cable, just to see if graph differences were due to something real or are just "accidental".  That's why I posted that the Gotham cable traces were identical in both sweeps and the Accusound traces had noticeable differences.

3. It is not my goal to determine how various cables compare.  My one and only goal has been to learn how two cables I own compare.  That leads me to a specific artistic goal.  Testing a variety of cables to learn how they compare does nothing for me.  I can't afford them and I don't have the time/will to make such tests.

So what's the purpose?  It is the one every engineer makes for himself/herself.  "Here is what I own.  Here is what I've run across.  How do these two things (and these two things only) compare?  Should I make a change or am I happy with what I have?"  This then is the story of my finding a new microphone cable that seems superior to what I own.

People who want a larger experiment should look elsewhere.  I am only reporting my experience.  I've probably done that to the limit I care to for now.  If another circumstance arises, then I might want to reconsider this issue for myself.  If anyone is interested I'll post that finding too.  Of course I am hoping others will make some sort of comparison for us to learn from.

4. I'm sorry (for myself) to learn GAC-2 cable is considered to be a poor wire.  I purchased it decades ago when it was sold as a Neumann product.  It was the best I could afford then and the best I knew about.  I now know about other cables as this thread has encouraged people to mention wires they've had experience with.  In no way do I think Accusound is a superior wire to anything other than the cable I've compared it with.  It is up to others to make further judgments.


Barry

[Kees de Visser]

Barry Hufker wrote on Fri, 29 June 2007 07:13

Testing a variety of cables to learn how they compare does nothing for me.  I can't afford them and I don't have the time/will to make such tests.

Wouldn't it be interesting to daisy-chain the two different cables (A & B) and compare the sound to A and B alone ? If A+B sounds like A, B is likely to be the (more) transparent cable (FWIW).
Perhaps the test is flawed from an electronical point of view. Comments much appreciated. (e.g. would the order be important ?)
It could also be interesting to daisy-chain 2 identical cables (A+A, B+B) and see/listen if that changes anything.

[Schallfeldnebel]

If you connect cable A+B and want to compare it with A, A should have the same length and the same amount of connectors, so you should double cable A. This going to be too complex.


Erik Sikkema
Schallfeldwebel