Suddenly Lost Stereo Buss Monitoring On The 388

Thanks for clarifying what you were talking about.

So you can’t hear track 2 where when the AUX buss pre/post fade source switch is in post-fade mode?
 
That's correct. But, to be clear, I can't hear it when I'm monitoring off the main stereo or pgm 2 busses either

I think that's clear. You might want to consult the manual; just in case
 
So basically you can’t hear any post-fade signal from channel 2 anywhere, anytime, correct?
 
So then it’s time to pull the bottom cover off and start checking where the signal stops passing.

Just to confirm, you don’t get signal to pass from the channel 2 EFF send either right?

Can you get signal to pass if you gently press down on the channel 2 fader knob with the fader level raised? How about if you exercise the channel 2 fader connector?
 
I haven't checked the channel 2 EFF send yet. I'll do it tomorrow and let you know then. I have my reverb hot wired to the effects loop, so i'm probably going to have to go through that

If I push down on the channel 2 fader cap, with the channel in RMX mode (L/R switch engaged), I can hear what I recorded recently faintly. likewise, if I turn the level on volume control for buss 2 all the way up I can hear the prerecorded material, but it cuts out and it's quieter than it should be.
 
Update. I can now hear sound (still faint) from buss 2 via the stereo buss without pressing down on the fader cap, and with the channel and stereo master faders in the shaded zone. Direct monitoring of pgm buss 2 is still roughly the same as before. I did try the Effects buss, but I didn't hear anything.
 
So yeah I think it’s simply signal on channel 2 is not getting past the fader, or there’s a failure further upstream. If you want to rule out the fader an easy test would be to swap the channel 2 fader with another channel and see if the problem follows the fader swap. If it does the fader is the problem.
 
I swapped the faders for channels 1 and 2 and here's what happened

I plugged a mic into channel 1, set everything to unity gain, assigned it to buss 1/track 1 and got signal. So the fader isn't the problem/

Then I plugged it into channel 2, assigned channel 2 to buss 2/track 2 and got, apparently, nada. I tried assigning channel 2 to buss 1/track 1 and got the same result as when it was plugged into channel 1 (so, a clear strong signal). I repeated this with both channels for the remaining six pgm busses/tracks, plus the stereo buss, and got the same result as I did for buss 1/track 1.

Just for the hell of it I decided to see what would happen if I tried monitoring buss 2 with the channel fader all the way up. I could hear something, so I pushed the buss B and stereo master fader to the top as well and recorded a short count to 12 to track 2. Playback through the monitor buss was lower in volume and somewhat distorted. Playback through the stereo buss on remix mode was fine. Even with the channel, Buss B and stereo master faders all at unity when recording.

I hope that made sense.
 
I'm also slightly concerned that nothing is coming through the effects buss and that the aux and effects buss master controls are both scratchy. Also, I have to have the aux master control all the way to the right to get any sound from the aux buss
 
Last edited:
Update. I've discovered why I wasn't getting sound from the effects buss. The effects send master control pot has been soldered in backwards. So, when I thought I was turning it up I was actually turning it down.

So that issue is definitely solved.
 
“…pot has been soldered in backwards….”

I can’t even comprehend how this is mechanically possible…they are PCB-mounted right angle pots…it only goes in one way, otherwise the pot would be upside-down, or on the wrong side of the PCB, and the pot shaft wouldn’t line up with the hole in the dress panel. Maybe it’s a reverse-taper pot?
 
So other input channels besides channel 2 are able to pass signal appropriately to PGM 2? And input channel can pass signal to all other PGM groups besides PGM 2?

If I understand correctly, then it seems at least one of your problems is simply a fault of some sort between the PGM 1-2 assign switch and the BUSS PCB.

Did you exercise the PGM 1-2 assign switch on input channel 2? Check the BUSS PCB connections for PGM 1-2 to the input 2 channel card. verify continuity between the assign switch and the BUSS PCB.
 
Yep, I can plug a mic into channel 1, assign it to buss 2 and record a clear signal on track 2. I can also do the same the other way (channel 2 to track 1). Ditto for sending signal to all other PGM groups from channel 2.

By BUSS PCB connections, do you mean the two Molex connectors at the bottom of each I/O board? Just to be clear
 
You must log in or register to reply here.
Back
Top