Channel Separation Listening Test

OK gang, my esteemed colleague has pescribed the following experiment to test for the audible threshold level of channel separation in my current competition vehicle:

(as posted by Kev7909)

I believe the experiment below would be better suited to what you are trying to achieve:

Use Cool Edit Pro (or whatever) to change the level of ONE side of a recording from 40dB to 20dB in 2dB steps. Therefore, one recording would have the left side 40dB below the right side in output for one disc. The next disc would have the output level increased to 38dB below the right side level, and so on and so forth until you get to the left side being 20dB below the right side.

Burn DIFFERENT CDs for this. Do not have all the tracks on the same CD. The reason is that you will know which track is recorded at which level. After you have burned the CDs have someone who was NOT with you while burning number them from 1-20 (or however much you burned). Have this person mix em up like a deck of cards before numbering. it is imperative that ALL of the CDs are IDENTICAL before numbering.

Have ANOTHER friend (not the person who numbered the discs) put each disc in the truck and you sit and listen. Have this friend record the number on the CD that you could hear the left side of the truck WHILE the right side was playing (remember, you did not touch the truck stereo).

Do this same experiment 10 times EACH for 5 or 6 people. The person who was recording the number at which the test participants could hear the left side must NOT take this test. The person who is doing the recording MUST NOT speak with ANYONE while the test is going on and nobody should see anybody else's 'number'.

Some of the participants might be people who have no idea what a car stereo is, or even care.

After the experiment is over, go back to the computer and figure out which CD was which using Cool Edit Pro or whatever software can read the dB levels of both sides of the disc. Now you will have a good idea of the crosstalk level that the average person (and more importantly, YOU) can hear in your truck.

Kevin

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Very well then. I was unable to complete the test due to waiting for my "assistant" Schreiber's to come over and number the discs and help with recording the listening results. However,
I have made the discs as precribed, here are the pix>

This is the track to be used.

Here is the screenshot of my audio card interface. I am shooting S/PDIF optical out in 2 channel stereo to my Philips CDR.

Here's a close up of the left and right channel output levels adjusted for the left channel 20dB down from the right channel.

Here's the display of the Philips burner showing the 20dB down track being recorded via Optical in...you can see the level indicators showing the drastically reduced left channel.

Here's the left channel down 41 dB !!!

and here's what the level indicators look like on the burner during the -41dB recording.

here are the 10 unmarked discs, recorded, and awaiting Jason's numbering system. I have listed the recording level on the paper Jason will use to create his disc numbering system and keep to himself for reference after the test.

Stay tuned