Setting azimuth without a scope... - Rod M - Vinyl Asylum

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Setting azimuth without a scope...

I was reading Andrew Chasin's guide to optimizing azimuth and am wonderng how it could be done if your preamp has no mono switch. He suggests that summing an out-of-phase signal will produce essentially no sound if azimuth is correct:
"This out-of-phase, or "null", test, can be performed in several ways. If you've got a test record such as the one produced by Hi Fi News and Record Review (and I recommend it highly), then you can simply make use of the azimuth test track it provides. This test track consists of a mono signal with the left and right channels out of phase. If your preamplifier has a mono blend switch (which sums the left and right channels), you can simply play the test track, engage the mono switch, and adjust the cartridge's azimuth until you hear minimal output through the loudspeakers.
In the absence of a test record with an out-of--phase mono track, you can simulate such a track by playing a mono record through a DIY phase-inverting cable. To build such a cable, buy yourself a cheap female-to-male patch cord from your local Radio Shack, cut one leg of the cable in half, and strip away some of the insulation around the copper conductors. Then, solder the positive conductor from one half of the cut leg of the cable to the negative conductor from the other half of the cut leg. Finally, solder the negative conductor from the first half of the cable to the positive conductor from the second half. Cover the exposed conductors/solder joints with electrical tape. You now have a cable that inverts phase in one channel. Now, connect the male end of your tonearm cable to the female end of the inverting cable you've just created, and connect the other end of the inverting cable to the inputs of your phono stage or the phono inputs of your preamplifier. Play a mono record (I use the DCC reissue of Sonny Rollins' Tenor Madness) and switch your preamplifier into mono mode. The azimuth of your cartridge can now be adjusted until you hear zero (or, at least, minimal) output from your loudspeakers."
Now, since I can't flip a mono switch, could I just run the stereo outputs from the phono preamp into a Y-cable (2 females to one male output) and plug that into just one channel on the preamp and get essentially the same thing?

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Michael Percy Audio

Topic - Setting azimuth without a scope... - Rod M 15:51:53 02/12/03 (12)

This "null" method for azimuth been soundly debunked by VK's article in the FAQ (nt) - john dem 18:18:17 02/12/03 (0)

Very accurate azimuth check without a scope... - giacomino 17:22:01 02/12/03 (2)

Interesting you should mention using a ...(long) - wbnormal 00:42:25 02/13/03 (0)

Re: Very accurate azimuth check without a scope... - Rod M 17:53:34 02/12/03 (0)

Re: Setting azimuth without a scope... - Rich Hollis 17:07:21 02/12/03 (7)

Re: Setting azimuth without a scope... - bkearns 01:18:55 02/13/03 (6)

Re: Setting azimuth without a scope... - Rod M 17:04:48 02/13/03 (4)

Re: Setting azimuth without a scope... - bkearns 03:23:20 02/14/03 (3)

Re: Setting azimuth without a scope... - Rod M 11:55:01 02/14/03 (0)

Re: Setting azimuth without a scope... - Junebug 06:15:37 02/14/03 (1)

Nonsense - bkearns 07:58:04 02/14/03 (0)

Re: minimum cross talk - Bruce from DC 06:52:58 02/13/03 (0)

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