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MV on SF twin reverb

3/31/2006 10:58 AM
Patrick Smith
MV on SF twin reverb
ok guys, this is gonna be a wierd request so bear with me  
I have a SF twin reverb that has had the following done (by me) to it:  
-PI and bias supply blackfaced  
-Normal channel routed through reverb circuit  
-Reverb channel with 500pf bright cap to be used  
as a bright channel with the normal channel ala Marshalls  
-both reverb and normal channels changed to tweed twin specs  
-Trem circuit disengaged, intensity pot replaced, and wired as a presence knob  
-MV removed and replaced with small jumper wire  
I'm a steel player and need LOUD and CLEAN which this thing does, absolutely smokes! BUT with the tweeding of both preamp channels the volume of this thing is horrendous and thus the most i ever get on both channel volumes is about 2 1/2-3  
SOOOOOOO, having said all that! :) It's going to sound like heracy but i want to reinstall the MV so i can back the volume of this thing down a lil bit and use the channel volumes a bit more.  
I hooked a MV last night up using regular hookup wire and it hummmed and buzzzed and made i unhooked it due to gigs this weekend (i want to play the amp)......did i miss something here? i need to hook the MV up with shielded wire? With the shielding grounded at one end, is that the ticket here?  
As always, mucho appreciation and thanks for any info or help  
3/31/2006 11:55 AM

Wasn't the original MV on yours wired using shielded?  
That's a lot of wire to go running around in there naked ;)  
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3/31/2006 12:26 PM
Patrick Smith

"That's a lot of wire to go running around in there naked ;)"  
truer words have seldom been spoken! :)  
yes, best i can remember the original was shielded, i guess it does matter, i mean who knew? :)  
Thanks for the input  
3/31/2006 7:15 PM
Don Symes

If you know, roughly, how much turn-down you need, what about just replacing the MV with a resistor divider right where you need it?  
(Give up a KNOB??!?!?)  
Ooorrrr, is there an unemployed hole in the back about where you want the master to be in the circuit?
4/1/2006 6:34 PM
Patrick Smith

i thought about using the extra speaker jack hole but i've actually used that, in contrast to the trem which i haven't used in 15 years or so. Plus, i have a '66 BF twin that is stock should that need ever arrise. The SF in question has been used exclusively for steel guitar
4/2/2006 12:49 PM
Don Symes

I got that - just trying to shorten, if not eliminate, the wires.  
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