Begin Phase Check: R/L Balance In The Middle - zapco DSP-Z8 IV II Owner's Manual

Begin phase check: R/L Balance in the middle

A. Tweeters ; Click to Mute ( 9 ) all channels except the tweeters. Note that tweeters are the
most difficult to phase. They are the smallest drivers and are not loud. You need complete
quiet. Play a music track of female vocal and notice where the vocal originates (you may need
to lower the crossover point for this. If so, keep the volume low and you may want to use a
48dB slope, so you do not blow tweeters. We have already set the calculated delay, so the
vocal should come from a specific location near the center of the windshield. If the tweeters
are not correctly in-phase, then the sound will not have a specific location. It will splash and
seem to come from everywhere at the same time. You will not be able to locate the sound at
a specific spot. To the left of the Delay bars you see the ( ) buttons. All should say 0 at
Phase 10
this point. Click the Right channel tweeter to 180 and listen for the difference. Do this a few
times and you will see that in one position the vocal is easily located near the center of the
window while in the other it seems to come from everywhere and cannot be located.
Obviously, you want the right speaker to be in the polarity that puts it in phase with the left,
so the image is centered in the middle of the dash. NOTE: Once you establish the proper
phase combination of a pair of speakers, it never changes. You do not change one without
changing the other as they are now a matched pair. If you have changed the crossovers of
the tweeters for phase check, you can put them back to normal now.
B. Midrange and Woofer/Mid-Bass ; Now mute all but the midrange. These are easier because
phase is more obvious at lower frequencies and because you can use more volume. The
procedure is the same but now you should use the male vocal. Listen for the vocal location. It
should be at a specific location near the center of the window. Change the phase of the right
speaker a few times and listen to the difference. Use the combination that puts the vocal in a
specific central location. Then you can mute all but the Mid-Bass and do the same as for the
midrange. Note; Another easily heard sign of phase in midranges and woofers is bass. When 2
speakers are out of phase there will be less bass. More bass in-phase/less bass out-of-phase,
listen for this in addition to the localization.
C. Subwoofers ; Woofers are the easiest. Play something with bass. The male vocal should
work fine. If you are using multiple woofers they must be in phase or your bass will go away.
When you change the phase of the right woofer it will be extremely obvious which polarity is
correct.
Note: Now you have phased each pair of speakers. Hopefully all are still 0, but if not it's OK,
but from now on they can only be changed by the pair. Never change only one driver out of a
pair. It's best to make a chart of speaker phases so you have it for reference later.