Tone control to tone stack...

[SteveJones]

Hi all,

I have a little single ended EL84 amp that started out life as a Kalamazzo Model 2. It currently has a tweed style preamp with a single tone control. I'm going to rebuild this amp in a larger cabinet to have a larger chassis and speaker.

I'm considering replacing the single tweed style tone control with a bass and treble tone stack, probably like the one in a blackface champ. But I don't want to affect the overall grit and grind of the amp which I like.

How much signal loss would I see using this type of tone stack over a simple tone control?

thanks,

Steve

[loudthud]

I have a silverface Champ with VTB controls. I like it better with the tweed style tone control and no feedback in the output stage. You could add a simple Bass cut contol that would be out of the circuit when the bass is all the way up.

[olddawg]

I prefer most single ended EL84 amps with just a volume control and that us usually all the way up. There is plenty if tone control in pickup selection and tone controls on the guitar. If you use a boost pedal with tone controls you are set. I run a stock VJ head through an open back cab with a 12" Eminence and use a Bad Monkey for an OD. It's a very loud and aggressive 5 watts. I use it so much that I have been thinking of building a 12" speaker open back cabinet EL84 5 watt combo myself.

[kleuck]

You can use a Bandmaster TS, in his book Merlin shows an improve model, still, there is a db loss in gain, so you can't really keep the same grit as with a Princeton Tone control. But you can modify the amp to get more gain from the triodes, on the schematic i found, there is no decoupling of the triodes, and you can use 220K plate resistors, or more (not sure the tremolo would still work the same).

[printer2]

You could increase the plate resistor to get more gain as kleuk says but you need a tone stack that has a higher impedance and does not load it down too much. Hey, I got one.