In article , Keith G
wrote:

"Jim Lesurf" wrote in message
...


I've also seen that. Also that they would drive two ESLs in antiphase
to check they could null the two outputs at the mic to confirm the two
speakers were near identical in performance.

How is that so hard - I would expect that with Lowthers?

Try it. Put the mic at the same distance (say 2m) from both, and drive the
pair in antiphase at the same level. Try doing this in your listening room
and if possible compare with doing it outside.

The problems a

A) most 'pairs' of speakers aren't actually that well matched in
sensitivity, frequency response, etc.

B) most chuck the power all over the room with a very poorly controlled
directionality pattern.

I was seeing the quads doing this 'on the factory floor'.

if you can play antiphase music, sit in the listening position and hear
nothing (or very faint) until you switch back to inphase mono, then your
system probably can give very good imaging. But if not, then you may find
the imaging isn't what it could be. Depends on the details, though, so
isn't that simple to assess.

This is one of the tests I tend to do when fiddling with speaker/room setup
to assess if I am close to a good arrangement. Can be quite revealing.

Slainte,

Jim

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