Anyone modded/upgraded OpAmps in VTB1?

[dickiefunk]

Hi. I'm in the middle of trying out new OpAmps in my VTB1. Has anyone else done this? What results have you had and what did you use?
I've replaced the 4580 on the XLR mic input with an OPA 2134 which has made the signal clearer and more focused. I'm now looking at replacing the OpAmp for the Line In/DI and the OpAmp at the Output stage. I've had a few recommended to me including :-

OPA 2134 - DI/Line in opamp

BJT 5532 - Output Stage opamp

LT 1469 - Output Stage opamp

OP 275 - Output opamp

Anyone had any experience with these? What would you recommend?

Thanks

[dickiefunk]

Surely someone out there must have tried this!?:confused:

[Ausrock]

I'm aware of a similar question over at Homerecording.com but as far as getting an answer here, you'll have to wait until someone from PMI who's knowledgable about these issues gets around to logging into the forum............you would probably be better off emailing PMI direct with your question.

:cool:

[Alan Hyatt]

Ok, well you can replace the 4580 op amps with the OPA2134's, and then replace all the 4580s with TL072s. I think doing that would get you a noticeable improvement.

Sorry for the long delay on this....

[dickiefunk]

Hi Alan. Thanks for your reply. There is a 4580 for the XLR Mic In (U1), a 2082D at the Line In (U2) and another 4580 at the Output Buffer (U6). Could you clarify at which stages I could use the OPA 2134 and TL 072's.

Thanks