[mellows]

Has anyone used a microphone before to test whether different cables etc make a difference to the sound produced in a music system?

You could have a specibly set up room with a microphone in a set position and then play some sound, perhaps a single frequency at a time for simplicity and then record it with the microphone with two different power cables or something. You could then analyse the recording on a PC and see exactly how much difference was made.

The owner of silentpcreview.com even has an anechoic chamber that he'd probably be willing to share.

 

[m1abrams]

Quote:

Originally Posted by mellows /img/forum/go_quote.gif Has anyone used a microphone before to test whether different cables etc make a difference to the sound produced in a music system? You could have a specibly set up room with a microphone in a set position and then play some sound, perhaps a single frequency at a time for simplicity and then record it with the microphone with two different power cables or something. You could then analyse the recording on a PC and see exactly how much difference was made. The owner of silentpcreview.com even has an anechoic chamber that he'd probably be willing to share.

Note really sure why a mic would be needed? It would add more variables that are harder to control. Why not just test the output of the cable directly?

 

[UNHchabo]

Quote:

Originally Posted by m1abrams /img/forum/go_quote.gif Note really sure why a mic would be needed? It would add more variables that are harder to control. Why not just test the output of the cable directly?

Because measurable differences in the cables do not necessarily equate to a measurable difference in sound.

 

[m1abrams]

Quote:

Originally Posted by UNHchabo /img/forum/go_quote.gif Because measurable differences in the cables do not necessarily equate to a measurable difference in sound.

But how would adding more variables to the measurement that have absolutely nothing to do with the cables going to give you anything meaningful about the cables ability to affect the sound?

 

[UNHchabo]

Quote:

Originally Posted by m1abrams /img/forum/go_quote.gif But how would adding more variables to the measurement that have absolutely nothing to do with the cables going to give you anything meaningful about the cables ability to affect the sound?

What he suggested was switching out the cables within the same sound system; take a sound system, and record a certain set of sounds being played through the system. Then replace one cable, and record that same set of sounds. If there are any differences in the recorded sound, then the cable is responsible for those differences.

You can test the electrical characteristics of a cable all you want, but this is the only way I can think of to objectively test if two cables have any difference within the context of audio playback.

 

[m1abrams]

Quote:

Originally Posted by UNHchabo /img/forum/go_quote.gif What he suggested was switching out the cables within the same sound system; take a sound system, and record a certain set of sounds being played through the system. Then replace one cable, and record that same set of sounds. If there are any differences in the recorded sound, then the cable is responsible for those differences. You can test the electrical characteristics of a cable all you want, but this is the only way I can think of to objectively test if two cables have any difference within the context of audio playback.

No wrong because a the only differences is not just the cable. The mic will pick up differences in temperature in the room since mics are affected a good deal by temp and so are the speakers. Any room noise which will not remain constant.

You can STILL use other methods of testing, since you do not care about the speakers take them out and tie the leads directly to the input of whatever you are testing is, might need to do a little voltage scaling and load on it since your capture device will want a lower signal. This scaling will add much less variance than any mic setup.

However the basis of your argument is that you will measure something via a Mic that you would not otherwise measure, and the only thing that will be is background noise. Only reason to use a mic to test a part of an audio system is to measure SPEAKERS or ROOM ACOUSTICS, everything else just feed the sampling device directly.

 

[m1abrams]

Quote:

Originally Posted by UNHchabo /img/forum/go_quote.gif You can test the electrical characteristics of a cable all you want, but this is the only way I can think of to objectively test if two cables have any difference within the context of audio playback.

Ok you are not going to use a mic to test objectively? You use human ears for that. Using a mic I assume you will capture the data and compare it.

 

[UNHchabo]

Quote:

Originally Posted by m1abrams /img/forum/go_quote.gif No wrong because a the only differences is not just the cable. The mic will pick up differences in temperature in the room since mics are affected a good deal by temp and so are the speakers. Any room noise which will not remain constant. You can STILL use other methods of testing, since you do not care about the speakers take them out and tie the leads directly to the input of whatever you are testing is, might need to do a little voltage scaling and load on it since your capture device will want a lower signal. This scaling will add much less variance than any mic setup. However the basis of your argument is that you will measure something via a Mic that you would not otherwise measure, and the only thing that will be is background noise. Only reason to use a mic to test a part of an audio system is to measure SPEAKERS or ROOM ACOUSTICS, everything else just feed the sampling device directly.

Sorry, I misunderstood what you meant; I get it now. When you said "test the output of the cable directly", I thought you meant the purely electrical testing I was referring to earlier, rather than a capture of the analog audio data being sent down the cable. I agree, that would be better than using a microphone.

Quote:

Originally Posted by m1abrams /img/forum/go_quote.gif Ok you are not going to use a mic to test objectively? You use human ears for that. Using a mic I assume you will capture the data and compare it.

Yes, I was suggesting we capture and compare the data. That would provide an objective assessment of whether we're recording the same data. Any comparison using human ears would be subjective.

 

[mellows]

What about the anechoic chamber I mentioned? If someone had the energy... What you could do then is play recording A to a listener with a short burst of recording B every few seconds, and if he can spot the different recording made by the different cable, he gets a medal.

 

[b0dhi]

Quote:

Originally Posted by m1abrams /img/forum/go_quote.gif No wrong because a the only differences is not just the cable. The mic will pick up differences in temperature in the room since mics are affected a good deal by temp and so are the speakers. Any room noise which will not remain constant.

It's a simple matter of ensuring constant conditions in the testing room to do the test as the OP suggested, and this is not hard so long as some diligence is employed.

I think the OPs idea is a good one. Although I doubt very much the result will be any different to those that have already been done, it doesn't hurt to try, and you just might learn something.

 

[mellows]

So who's gonna do it?

 

[loopsider]

This is not a bad idea, but its probably better to feed the signal directly. Its really not that complicated to then compare both signals through frequency analysis (or FFT if you are so inclined). Though using a mic would help with people that feel that there is a certain "synergy" between their cables and speaker/transducer.

 

[mellows]

Well we can leave it to the people with magical cables to test. And if they find any difference, they get the medal I promised. Great sig by the way.

 

[Iniamyen]

Agree, I think the advantage to this is that you could potentially get around the "it's not measurable but it's audible" argument when you only measure analog signals on the cable.

I don't know how mic accuracies compare to human ear accuracies, but my guess is they are a lot better.

 

[Punnisher]

You are adding another variable in the chain, making it even harder to detect change.