Wisdom Audio DCAB-1 - Manual (Page 31)

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A Quick Overview In principle, the calibration process is fairly straightforward.
For the Left Speaker 1. Establish the preliminary crossover frequency between Low Frequency
Regenerators (LFRs) and Planars and set the rough levels.
2. EQ the planar section first: boost the bottom of their range, cut the typi-
cal peak around 6-7 kHz, and then tackle the largest remaining problems
from the bottom of the range, working your way up.
3. EQ the LFR sections: work on the biggest problems from about 50 Hz
on up to the crossover; then use the Bassis controls to pull down the last
bump in the bass (usually between 40-50 Hz) and extend the response
deeper.
For the Right speaker Repeat the process described for the Left speaker, above.
Compare the Two Speakers Then compare the results of the two, and fine-tune things to make the two
curves lay over one another. The best-focused and three-dimensional imaging
is achieved when the two speakers are extremely close matches to each other,
despite whatever differences your room might be superimposing on them.
Detailed instructions follow below.
Set the Crossover The crossover frequency is determined by the size of the planar magnetic sec-
tion of your loudspeaker.
• 50-inch planar = 190 Hz (the Adrenaline M50)
• 75-inch planar = 155 Hz (the Adrenaline M75 or Rush)
These crossover frequencies are starting points, and usually end up being the
correct settings. You may fine-tune them by as much as 10 Hz or so toward the
end of this process, based on the performance you are achieving in your room.
Set the Levels Start with both the hi level and the lo level controls at 10.0 dB. Set pink to
3% and set the left channel pinkin to on. Bring the volume up (using pink) to
a moderate volume, one that is loud enough to get well up above background
noise, but not so loud as to drive you from the room. With most amplifiers, a
setting of 5-6% is fine.
Looking at the average volume of from 50–150 Hz and from 300Hz–10kHz
(ignoring the extremes for the moment), adjust either the hi level or the lo level
control for the left speaker to bring them even with each other. It is difficult
to get this perfect before you flatten the response. Don’t worry about perfect,
but try to get it close. (You may see an obvious step from one to the other if
you have amplifiers with different gains on the low and the high sections of the
speakers. This is fine — just fix it before moving on.)
If your amplifiers have the same gain and behave well into lower impedances,
your initial settings will probably be approximately as follows:
• M50 hi level = 9.0 dB lo level = 15.0 dB
• M75 or Rush hi level = 10.0 dB lo level = 10.0 dB