UTC Resonant Eqaulizer

[Aisjump]

hello. I found this old UTC type CGE-1 REsonant Equalizer put in this old Tube preamp thing that uses 6C5 tubes. The preamp is a homebrew thing, and seems really thrown together... also like it was never quite finished.
the unit has an interesting sound... but is really noisey, and has alot of hum... not to mention a noticable loss of highs. i've had it looked at and this is as good as it gets.
What I'm wondering is, since it is a passive equalizer, inductor based... can I just put it after another preamp? in between the output of the pre, and the output transformer? any suggestions?

-steve

[Aisjump]

maybe I could be a little more clear on what I mean... I'd like to take the EQ out of the current preamp its in, and put it in something else.
if I have a preamp card, send the output through the UTC, and then to the output transformer... would that be fine?

-steve

[winky dinglehoffer]

I'm not familiar with the UTC eq, so I'll just speak to passives in general:
basically you input a line level signal and then at the output you'll need makeup gain, probably in the range of 10-20 db, to make up for the attenuation of the signal by the eq.

If the utc is a modular unit like the old Langevins (251 & 252), it shouldn't be a problem to remove & use with whatever.

Pics would be nice, & might lead to some better advice from someone more knowledgable than I.

Tom

[brianroth]

The only info I found was from an Olde UTC catalog. See the lower left of this page:

http://www.brianroth.com/library/utc-pg29.pdf

Bri

[Aisjump]

wow thanks Brian. That is the only information Ive ever seen on this thing!

[brianroth]

Looks like you'll need a high impedance "follower"/amplifier at the output. Something with a FET input, most likely, if you want to move away from tooobz.

Bri

[winky dinglehoffer]

I'm still a bit curious about how the eq is hooked into your mic pre. Is there a makeup gain stage directly after the eq? I'm thinking that if there is one, you could probably, at least on an experimental basis, hook in just about any line level source to the eq input & use the makeup gain stage that's already there. That might bypass most of the noise issues you have & give you a way to use the eq without too much work.
And if there isn't a makeup gain stage, there might be an impedance mismatch on the out of the eq that could potentially contribute to your noise problems in various ways. I'm certainly no expert, but it might be worth looking a little deeper into the mic pre's circuit before taking it apart.

Tom

[brianroth]

The UTC catalog indicates it can accept a signal source with an output impedance up to 20,000 Ohms (no big deal with modern circuitry), but it also needs to be fed into an 18 dB "makeup gain" stage with a high input impedance.

Bri