studio pre mod

tubeydude · Apr 5, 2007

Has anyone done the input gain mod I got the schematic from Mesa? Does is just allow you to lower the overall gain of the pre?

Anyone have pictures? Has any one made it easily adjustable from the outside of the unit?

Thanks,

Erik

disassembled · Apr 5, 2007

This isn't a real technical board so most people don't mess with their stuff. What kind of mod is it?

Off topic....I have a triaxis and 290 combo and just bought a MK IVB that I won't be touching until July. I am thinking of getting rid of the TA because the EQ is really what makes these amps IMO. Is the TA comparable to the Studio Pre? Would you get rid of one or the other because of redundancy? I am so happy with my TA but the lack of boogie graphic eq kind of bums me out and that's really the only reason I would switch to another pre.

I was thinking of modding my TA to have a 100% mix of the dynamic voice (just like the amp heads). I can't see anything about mix control on the schematics I have though.

Greg

tubeydude · Apr 5, 2007

Yeah I wouldn't know how to change the mix value in TX.

Regarding the TX vs. Pre:
The Pre sounds really good. I think it is a bit more dynamic and has a bit more high end response. I am mainly going to be using them both for recording in my small garage studio. I will be mainly using the record outs to track songs and then do miced cab overdubs as necessary. The record on the Pre does sounds better than the TX. This is the main reason I'm wanting to see if the op-amp swap will breathe some life in tot he rec out of the TX. The pre doesn't seem to any op-amps in it at all...hmmmm

TX Rec out: A bit compressed and tight. Not as bright. Endless tone possibilities

Pre Rec out: More dynamic and bright. More touch sensitive. Not quite as many sound options

The TX can of course get many more sounds than the Pre, but the pre seems to have a bit more "life" to it. Just comparing the rec outs here. I have not done a side my side through the 2:90. I'll probably put he TX into one side and the Pre on the other and see what's what. Should be a good way to spend a sat afternoon.

Hope that helps..

Erik

disassembled · Apr 5, 2007

I don't use the record outs as I really don't record that much (I need to better my playing than record the nonesense that I play). I don't think an op amp change will make the tone better on the record out but it will probably affect headroom and lower the noise floor. If you want to change the tone of the output you could probably screw with the caps on the record out.

I think i found the mix LDR on the schematic but i am not positive so some testing will be in order. I would really like to keep the TA to compare with the MK IV when I get a chance to go home. Having the studio and the TA would be overkill for sure and I won't even entertain having both unless I run into a rediculous amount of money to blow on as many toys as possible.

I have a behringer direct box with speaker emulation that lacks a lot of high end but you might have better luck finding an external speaker emulator that will work well with any preamp.

Greg