µ-Dimension Glow DSP8 Instruction Manual page 47

on that channel, start with the delays on the two speakers in the lowest
frequency ranges (i.e. mid-bass and midrange), and work up in
frequency through the delays.
When the first channel sounds as good as possible by itself, move
on to each of the other channels, and use the same procedure for
each.
When all of the channels have been adjusted individually, it is time
to adjust them relative to each other. For systems with only a single
seat SQ requirement, start with the left and right front channels,
listening to music with a known center image in the recording. Now,
adjust the delay on the near side channel so that the apparent center
image moves to dead-center in the soundstage. Then, turn on the
center channel (if one is used), and adjust it's delay so that the center
image is as focused as possible, and the overall tonal balance is best.
An RTA can also be used to look for the best overall frequency
response, but it is quicker to do this step by ear. And, you will have to
check it by ear after using the RTA anyway.
For a multi-seat position SQ system, after each channel has been
set individually, look at the delay settings for each pair of matching
speakers on the left and right front channels. If there are significant
differences between, for example, the midranges, you will need to
listen to the system with all of the speakers in both channels playing,
and adjust the delays on the midranges to the same setting, which
should be somewhere between the values determined for each
channel individually, to yield the best overall SQ. You will need two
experienced listeners, one in each front seat for this part of tweaking
the delays. This can get tricky and sometimes confusing. The idea is to
set the delays to the same value for both mids, both tweeters, etc. and
listen for the best compromise delay settings for both seats, as the
delay setting is swept between the high and low values determined
before. The end result will likely be a compromise delay setting, and
possibly neither seat will be maximized for SQ. But, both seats can
sound very good, and neither will have a significant SQ advantage
over the other.
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