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System Phasing
: Before you start the equalization you want to be sure the system is
phased properly. Below we offer one system to help you phase the system.
You were promised more on polarity. Before equalization you should assure that all
speakers are in phase as a system at the listening position. All speakers need to have the
same polarity so they move the same direction at the same time. If they are not, you will
not be able to get a proper tune. There are a number of methods for doing this. We offer
one.
Tweeters
: (A) Mute all speakers except the tweeters and play a high female vocal soloist.
You should hear the voice at a single point near upper middle of the windshield. If the
speakers are out of phase the voice will not be localized but will seem to come from
everywhere. To test, using the Phase buttons, change the phase of the right speaker and
listen for the difference. Do this a couple of times as needed. The position that puts the
voice in a small single
location on the window is the correct phase. (B) Note where the Tweeter center is located.
It should be just slightly above and to the left of the center of the windshield (for left
hand drive cars). If it is off to the opposite side of center or too far to the left, and if you
have measured correctly, then you have a gain
difference and you can correct by a slight level adjustment reduce the right tweeter to
bring it left or reduce the left channel to take it right. No more that 1dB or 2dB. Now the
tweeters are set. From here on out you cannot change the levels or phase of either
tweeter.
Mids, Mid-bass (woofers), and subs
: Now mute the tweeters and un-mute the
midranges. The process is the same for each pair of speakers. The sound should come
from a single focused point near the center of the windshield. For midranges and larger
drivers, you want to use a deeper male vocal. The larger drivers are much easier to tell the
differences between in-phase and out of phase. Also, with the larger speakers you will hear
a dramatic reduction of bass if the speakers are out of phase. So, for midrange and larger
speakers you will look for a focused sound source in the windshield with stronger bass.
NOTE: Once each channel pair is adjusted, they cannot be separated. Any change of phase
must be done by the pair.
Phasing the pairs
: Again, listening to a single vocalist. Mute all channels again except
the tweeters. Then bring in the midranges. If these pairs are in proper phase the sound
should be near center in the upper part of the windshield. If they are not in phase the
sound will be pulled down lower. You can reverse the phase of BOTH mids now and
listen for the difference in the sound location. Choose the phase position that puts the
sound high near the center.
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Gain
: Gain can be adjusted by using the up/down arrows when the band’s EQ dot is
highlighted. You can also click into the gain or Q rows of any band and adjust with the
up/down arrows. You can move from one band to the next with the right/Left keyboard
arrows.
Q Setting
: Q can be set as above using the keyboard arrows. You can also make rough
adjustments by dragging one of the green boxes in the EQ graph to make Q wider or
narrower to affect a smaller or larger group of frequencies with your EQ adjustment.
To aid the tuning process you can temporarily bypass a channels equalization. You can
also the reset function to reset one channel or to reset all channel to default positions
with no equalization.
