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The good news, the noise is gone now
Lest we lose sight of that, I'm glad THAT issue has been taken care of!
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but the bass and high frequency are off phase
Hmmm...
I'm wondering if the issue might be the (slight) difference in signal processing delay between the digital and analog outputs and the current spacing of the L1's ... or a funky T1.
A few thoughts on how we might validate this conjecture:
D) Verify it is NOT a 'dual mono' issue. Two ways to check for that possibility:
D-1) Separate the two L1's (and their associated stacks of B1's) by at least 20 feet. If the 'cancellation' is really a 'dual mono' cancellation, this separation should eliminate it for much of the listening area.
*** This may be all you need to do for your outdoor gig coming up -- particularly if you don't have time to do the more thorough diagnosis possibilities I outline below. *** D-2) Use a truly common analog signal between the two L1's. To do that, you'll need a "Y" cable (and a separate means to power the T1, if that is to be tested as well).
Put the two L1 columns as close as you can get them, and put the two stacks of B1's side-by-side behind them (as a 2x4 stack, if using the A1's).
-- Initially, use one channel from your mixer. Feed it through the "Y" to both "L1's" (the T1 is not involved in this part). Start with just one of the two L1's (turn the Trim on the other all the way down). Get to a comfortable listening level with just one L1, then turn up the trim on the other L1 -- what happens to the sound? With the columns and the B1's physically real close, you should not be getting much 'dual mono' cancellation. If you do, it would primarily be in certain bands of the mid-upper frequencies, not the low frequencies.
-- Assuming that is good (direct from one mixer channel), try both mixer channels direct to the L1's (without the "Y"). It should sound just as good, or even better, than it did using one mixer channel and the "Y" cable.
Let's call this setup above (D-2) the "Mixer Direct" approach.
E) Now, to check out the T1:
Leaving the two L1's real close, go back to the "stereo T1" setup, with one mixer output into (say) Channel 1, going to the T1's Master output. The other mixer output goes into (say) Channel 2, and that output is directed SOLELY to the AUX output
(its channel volume would be all the way down, and the AUX setting would be Pre-fader, so it's volume is controlled only by that channel's Trim)E-1) If you have a separate T1 power supply, you should be able to verify that the sound from this setup is the same as what you got with the "Mixer Direct", by using both the analog outputs (Master 1/4" and Aux 1/4") from the T1.
Does this sound the same as the "Mixer Direct"? If not ... then something is really 'funky' -- it should sound the same (the various Trim knob settings may be different in order to get the same volume from both L1's, but the resulting sound should be the same as with the "Mixer Direct" connections).
If the same sound, all is good with the T1 connections.
If different, then it may be that the T1 is bad (e.g.: has one of the connections reversed between the Master and Aux channels).
Now, assuming that the "fully analog with T1" is o.k., it's time to test if it is the digital vs. analog delay that is the issue.
E-2) Remove the analog cable from the T1 Master (both ends of the cable!), and power the T1 using the digital cable ... which also will provide the "Master" audio output to that L1
(the one that no longer has a 1/4" cable in it).
What does that do to the sound?
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If you don't have a separate T1 power supply, then you can't really do setup "E-1" ... but you may still be able to tell if there is a significant different between "Mixer Direct" and the T1-based connections. If so, call Bose Support -- the normal additional delays between the Master digital and the Aux analog should be so small as to not be noticeable without very careful listening.
