Opamp Labs equalizer.

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Just give them a call and ask for their catalog. They have the schematic of a Model 109 EQ using the 325EQ opamp in it. (323) 934-3566 They're in Hollywood, so it shouldn't take to long to get the catalog.

It's funny you should mention Opamp Labs, I am going there later on today to pick up some inductors. http://www.opamplabs.com/87.htm

Cheers,

elco
 
[quote author="NewYorkDave"]Hey Elco, while you're there, could you ask for a datasheet for the (discontinued) model 325L limiter? I recently acquired a small batch of these, and have no data on them at all--not even pinouts. I wrote to Bel about it, but haven't received a response.[/quote]

Thats a 10-4 good buddy. :thumb:
 
Here's some more Opamp EQ Schematics - Two, and Three band:


http://home.mindspring.com/~redbugg/OpampEQ2.jpg

http://home.mindspring.com/~redbugg/OpAmpEQ3.jpg


Download 'em soon if you want, as I probably won't leave 'em up for long.
 
Dave;
Thanks for that when I saw the 109 EQ I lost it.

Bluebird I assume the 325EQ is a plugin module
like everything op-amp makes!
Cool do you have a datasheet on the 325EQ module only.
 
I've got a 16 ch Opamp Console that I was thinking of parting out. Maybe sell some "channel strip" kits, with a 360 mic amp/xfrmr, a 325 EQ amp with 2 band LCR assembly. No o/p xfrmrs though, as there're only four, which on the o/p busses. These would also include gain switch, the eq pots/switches, knobs, and the octal op amp sockets. I'd pull 'em out trying to keep most of the wiring intact. There'll be about a dozen available. I guess I'll have to think of a price now................hmmmmmm.
 
> datasheet for the (discontinued) model 325L limiter?

Can you crack one open? I've always wondered what was inside those cans. What VCA technique? They are old enough not to use any of the usual-suspect chips. So low-voltage and compact that a tube is highly unlikely. The specs don't look right for Opto, yet opto would explain why no external timing controls (there are plenty of N/C pins available).
 
Bryson,

Thanks for the link to the datasheet. It's not linked on OpAmp's main page, so I didn't know it was there.

Personally, I think it's a shame to part out unusual old consoles, but hey--it's your choice. Here's a schematic for the 12-channel version of that console:
http://music-club.rutgers.edu/headfonz/NYDave/opamplabs-1204TV.jpg

How about trying to sell it intact before resigning to part it out?

PRR,

I only have seven of the 325L, so I'm reluctant to sacrifice one to science. I'm pretty sure OpAmp modules--at least the small signal models--are potted. But perhaps Bel from OpAmp would be willing to divulge some info about what's inside, since it appears to be a discontinued product.
 
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