thefastvinny
Well-known member
This is the first time I have seen this console, let alone try to troubleshoot any issues. So there is a very interesting problem going on that I can't quite rap my head around. Upon commissioning the desk, I found about 9 Channels that would not pass audio with the EQ in that respective Channel Path (Line Input - EQ to CH Switch up; Mix Input - EQ to CH switch down) regardless of the EQ being turned on or not. I assumed that it was going to be a modular problem and had the Channels sent to a repair shop that had the test jig. We got them back and after further investigation, the issue still persisted. I later found the problem to be the slot that the modules came from. A couple of these Channels in question were swapped and the bad ones worked in different slots. Even more investigation, it appears that the Insert Rtns are not passing audio as well. Make sense to anyone or improbable coincidence? From earlier though, All audio paths DO pass audio with respect to the EQ to CH switch.
A little bit of history on how this console was setup by previous owners:
They were using an automation system at one time, what and how is unknown, but they had cut traces on the patchbay in the Insert send/rtn and hardwired them to a Mackie Ultra 34. The reason of this, I have no idea but apparently it had something to do with the automation system. The Mackie unit is all that remains of the system and is in constant bypass mode.
So from here I went to look at the Patchbay and craftsmanship of the wiring to the Mackie unit. It has deteriorated quite a bit and needs re-worked, or just return the desk to original working order. By simply wiring the send and return together to see if that was the cause of the issue, I found that it is most likely not the case.
After a few minutes of deep thought and some soothing tunes, I decided to check a good Channel VS. a bad Channel. Found that on the bad Channel, the + leg of the Insert points were nearly shorted to ground at about 78Ohms. This short would go away when the PSU was shut off, and/or when the Patchbay ribbon connector with those points were disconnected.
Any thoughts on this madness???
Sorry for the lengthy post but I had to explain in detail because it just doesn't make sense to me.
V
A little bit of history on how this console was setup by previous owners:
They were using an automation system at one time, what and how is unknown, but they had cut traces on the patchbay in the Insert send/rtn and hardwired them to a Mackie Ultra 34. The reason of this, I have no idea but apparently it had something to do with the automation system. The Mackie unit is all that remains of the system and is in constant bypass mode.
So from here I went to look at the Patchbay and craftsmanship of the wiring to the Mackie unit. It has deteriorated quite a bit and needs re-worked, or just return the desk to original working order. By simply wiring the send and return together to see if that was the cause of the issue, I found that it is most likely not the case.
After a few minutes of deep thought and some soothing tunes, I decided to check a good Channel VS. a bad Channel. Found that on the bad Channel, the + leg of the Insert points were nearly shorted to ground at about 78Ohms. This short would go away when the PSU was shut off, and/or when the Patchbay ribbon connector with those points were disconnected.
Any thoughts on this madness???
Sorry for the lengthy post but I had to explain in detail because it just doesn't make sense to me.
V
