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Vintage threads from the first ten years

disconnecting the tone stack

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6/29/2000 3:30 PM
JCS	disconnecting the tone stack I seem to remember reading, you can disconnect the tone controls on one channel of a blackface fender (deluxe) and get a tweed type sound. More mids and more gain I believe. I tried lifting the 6800 ohm res on the bass pot. It seems to do the trick. Any advice on this or similar mods would be appreciated. Thanks Jim

6/29/2000 3:53 PM

You may want to try replacing the 6.8k with a higher value, up to 25k.I know that modding a blackface is considered a mortal sin, but you could disconnect the 'bright' switch and use that(if it has one) or install a switch in place of an unused speaker jack, then switch between the stock 6.8k and a higher value. Don't drill any holes or the Gods of Vintage will frown on you, and the value of your amp will go down faster than a pint of Bellhaven at a Bon Scott memorial dinner.

6/29/2000 4:18 PM
Trace	Yes, just lift the resistor from ground and that will bypass the tone stack. Richie had a good idea and it works pretty nicely, remove the 120pF bright cap and then wire the resistor to the switch and the other end to ground. This way you can switch back and forth! Trace

6/29/2000 5:10 PM

Richie? Who's Richie?
I am toying with taking this same idea a little farther by having it footswitchable for solos to add some mid boost.Unlike your blackface, I have a modded silverface, so I can do this without fear of retribution from above, although I understand that even some silverface fender's are becoming desirable because the blackfaces are too expensive and (probably mostly) due to this silly infatuation with all things 70s.Good luck with your experimentation.

6/29/2000 5:29 PM

quote:
"the value of your amp will go down
faster than a pint of Bellhaven at a Bon Scott memorial dinner. "

wish I'd said that

quote:
"although I understand that even some silverface fender's are becoming desirable "

In Southern California just say: "Fender tube amp" --and any other brand you can think of.

-Eric

6/29/2000 9:43 PM
JCS	Thanks for all the replies. How about using the ground switch ?(no bright switches on deluxe) I installed a 3 prong cord on it, so I don't need that. I also like the footswitch idea, could I somehow use a 1/4" jack and use a generic 1/4" plug footswitch ? Any input is welcome. Thanks Jim

6/29/2000 10:02 PM

Hi Jim,

The ground switch is not in a good location for doing this kind of thing - you will be running wire over to the noisiest part of your amp, and that is asking for trouble with oscillations and hum (not to mention it is bad form).

For the Deluxe or Deluxe Reverb, I propose this: Every old Fender has two input jacks for each channel, but almost nobody uses both jacks on the same channel at the same time. Just use one of the input jacks (say #2 of Vibrato side) as a footswitch jack to switch the tonestack in and out. The jack is right near the controls, so wiring would be a cinch, and it is easily reversible. Use a shielded, quality cable for your footswitch hookup, and you should be good to go.

Just an Idea,

Reverb

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