FA: Urei/JBL 7510A 16ch preamps UPGRADED OPAMPS & CAPS

F

flyingeyepro

New member
The JBL/Urei 7510A is a 16 XLR in, 16 TRS out, mixer with direct outs.This was intended as a automatic mixer for board rooms or bowling alleys. JBL had recently purchased Urei and used a nice preamp circuit board containing a LM394 and a TL074 (fixed gain), passing thru a 5532 as the variable gain stage. I have professionally modified this unit. The main input caps have been replaced with Nichicon Gold caps. The mic preamps have been isolated from the gate/mixer portion of the circuit. It was basically removing a socketed gate IC (4066) from each channel and lifting one side of a resistor. It can be returned to stock, but I like it like this. The 2nd stage opamps were 5532s, which I swapped to LM833s. I'll include schematics, 4066s and 5532s, so it can be returned to stock with the exception of the input caps. One of the XLR tabs is broken (ch. 1) I use a short XLR to make it easy. The jack is an obsolete part. Replaceable, but it would require drilling. I apologize for the poor photo, I'll provide better hi res pictures if you like. All channels sound great. The mixer portion works, but that's not what it excels at.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=320487208435

Thanx
Chris
 
Chris,
So is what you are saying is there is no adjustable gain per microphone?
Is there Phantom power ?
Does it have enough headroom to track drums through?
 
No, that's not what I'm saying. I'm merely describing the circuit as it is layed out. Google the schematic if you'd like to follow. I have tracked drums with it just fine. Some mics require pads, if they are very hot. It does have global phantom.

Thanx
Chris
 
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