Don't go changing opamps willy nilly

[scott2000]

I don't like the pot across the NF path of an op amp alone... Wiper bounce, or a faulty pot will result in no feedback, a bad thing for op amps.

JR

PS: I vaguely recall a design issue with one of those RANE products that required an engineering change... Have you checked with RANE?

Thanks!

No I haven't checked with Rane....This model isn't even listed on their site under discontinued items. I can't find an accurate schematic anywhere although it's pretty similar to the 90's version except for some placements and the power supply......

Quick look and I see it's the same POT SET UP in the 2003 models ....

I'll send them an email to see what they say......  It's like a real low frequency oscillation that happens briefly........ And it doesn't go beyond 30 or 40 hz.......  pretty weird..... The things sound pretty good actually...but this can't be a good thing in a live situation if there's no filter in place......

..I just happened to notice when I had my software analyzer opened and no signal going in........

Looks like goofy stuff from a couple tube things I have seen that'll oscillate if there isn't an input connected .......but they don't settle like this issue does......

Thanks again!