Using a tweed single knob tone control for bass reduction instead

[Tone Junkie]

I think a tweed tone control , if im not mistaken is a treble reduction control.
 Is there any way to make it work as just a bass reduction control.
Thanks Bill

[chocopower]

i have seen something like that, but i,m still wayting to test it.

Is like a Orange bass cut control, but with a pot instead a rotary switch.

[Fresh_Start]

sure - just make it a high-pass filter instead of a low-pass filter.

http://www.duncanamps.com/technical/tonestack.html

http://www.angelfire.com/electronic/funwithtubes/Amp-Tone.html

You could use the bass portion of a Baxandall stack too:
http://www.duncanamps.com/technical/tonestack.html

Cheers,

Chip

[loogie]

You could also check out some of the old Gibson schematics like the GA25.

[Tone Junkie]

I guess I should really give exactly what Im looking for, I like adding extra gain stages but there always to bass heavy with standard values I want a single tone control that effects the bass only you guys gave me some good areas to look at i will study somemore.
Thanks Bill

[HotBluePlates]

There is another way, but I'm not up to speed on my drawing program's features yet. You'll have to be satisifed with a verbal description until someone like Sluckey comes along and draws it for you.

Put two coupling caps in series. The first cap should be large enough to let through all the bass you'd ever want; that may be from 0.022uF up to 0.1uF, depending on the resistances in your circuit. The second cap should be small, say, 0.005uF or 0.001uF (experiment to find a value you like).

Now place a pot wired as a variable resistor across the smaller cap. That is, your normally ungrounded outer lug connecting to the junction of the two caps, and the wiper connected to the output of the smaller cap. The free leg of the other, bigger cap is the "input" of this whole circuit. It should go to the plate of the previous tube stage. The wiper/output of the smaller cap is the "output" of this circuit, and goes to the following stage's grid and grid reference resistor. This wiring results in more bass as you turn the pot "up". You can use the wiper and "normally grounded lug" for more "treble" as you turn up.

NOTE: no lug on the pot actually runs to ground; the term is used to help you visualize.

You'll want a 1M pot for this circuit.

It works like this:
Two caps in series behave somewhat like resistors in parallel. The total capacitance will be smaller than the smallest cap. For our example of 0.047uF and (say 0.0047uF), the total capacitance will be 0.0042uF.

If you imagine the pot being at full resistance, it looks like a high impedance to the signal, which then goes through both caps. The effect is a small coupling cap, and very much rolled-off bass. When you reduce the resistance of the pot, more signal is able to shunt around the smaller cap. With the pot resistance at zero, the small cap is out of the picture, and the bass response is set by the larger cap.

There is no crackling noise with the pot, because the larger cap acts as a blocking cap.

This is "same, but different" as chocopower's circuit. You could just as easily use his cap values instead of the ones I suggested.

[JayB]

There is another way, but I'm not up to speed on my drawing program's features yet. You'll have to be satisifed with a verbal description until someone like Sluckey comes along and draws it for you.

Put two coupling caps in series. The first cap should be large enough to let through all the bass you'd ever want; that may be from 0.022uF up to 0.1uF, depending on the resistances in your circuit. The second cap should be small, say, 0.005uF or 0.001uF (experiment to find a value you like).

Now place a pot wired as a variable resistor across the smaller cap. That is, your normally ungrounded outer lug connecting to the junction of the two caps, and the wiper connected to the output of the smaller cap. The free leg of the other, bigger cap is the "input" of this whole circuit. It should go to the plate of the previous tube stage. The wiper/output of the smaller cap is the "output" of this circuit, and goes to the following stage's grid and grid reference resistor. This wiring results in more bass as you turn the pot "up". You can use the wiper and "normally grounded lug" for more "treble" as you turn up.

NOTE: no lug on the pot actually runs to ground; the term is used to help you visualize.

You'll want a 1M pot for this circuit.

It works like this:
Two caps in series behave somewhat like resistors in parallel. The total capacitance will be smaller than the smallest cap. For our example of 0.047uF and (say 0.0047uF), the total capacitance will be 0.0042uF.

If you imagine the pot being at full resistance, it looks like a high impedance to the signal, which then goes through both caps. The effect is a small coupling cap, and very much rolled-off bass. When you reduce the resistance of the pot, more signal is able to shunt around the smaller cap. With the pot resistance at zero, the small cap is out of the picture, and the bass response is set by the larger cap.

There is no crackling noise with the pot, because the larger cap acts as a blocking cap.

This is "same, but different" as chocopower's circuit. You could just as easily use his cap values instead of the ones I suggested.

I never could get that to work like I wanted it too. There was always this sticking point in the middle of the pot where it was all on and it just bugged me to death.

I do something similar but sort of different that works like a charm for me. I suggest using this, it'll bass reduction. Just before this circuit in series, is a .1uf cap. Use what ever cap you want. Hate giving up my secrets.



 

[HotBluePlates]

... Hate giving up my secrets. ...

I promise to steal it immediately! 

Thanks for sharing. It looks like a smart way to get around the issues you were having.

[JayB]

... Hate giving up my secrets. ...

I promise to steal it immediately! 

Thanks for sharing. It looks like a smart way to get around the issues you were having.

Patent pending. 

It's still interacts with a volume or gain pot but it works.

[tubenit]

For consideration ..........

I've used both of these treble and bass controls on Carolina Blues Special amps.
The CBS schematic shows a Dano treble bass control.

With respect, Tubenit