Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Jonas on July 12, 2024, 04:57:43 pm

Title: Tone Stack Calculator
Post by: Jonas on July 12, 2024, 04:57:43 pm

Hello,

When using the Tone Stack Calculator, how is the RIN and RL value set?

Title: Re: Tone Stack Calculator
Post by: dwinstonwood on July 12, 2024, 05:05:33 pm

Read starting at the bottom of p.29 of this document:
https://www.valvewizard.co.uk/Common_Gain_Stage.pdf
RIN is about 39K for a 12AX7.

Title: Re: Tone Stack Calculator
Post by: HotBluePlates on July 12, 2024, 09:32:31 pm

Quote from: Jonas on July 12, 2024, 04:57:43 pm

When using the Tone Stack Calculator, how is the ... RL value set?

Compare the schematic to a Fender amp.  "RL" is in the position we usually see a Volume control in the output of that particular Fender tone stack.  Fender usually used 1MΩ Volume pots, so that is the value we might choose for RL (unless your specific amp has a 500kΩ pot in that position).

Title: Re: Tone Stack Calculator
Post by: Jonas on July 29, 2024, 04:46:26 pm

I've been tweaking the values on the Big Muff and came up with this....

Looking to build a one knob "tilt" tone control. Any thoughts on this? is there a better circuit out there?

Title: Re: Tone Stack Calculator
Post by: tubeswell on July 29, 2024, 08:03:16 pm

Quote from: Jonas on July 29, 2024, 04:46:26 pm

I've been tweaking the values on the Big Muff and came up with this....

Looking to build a one knob "tilt" tone control. Any thoughts on this? is there a better circuit out there?

Looks Pretty good


(Doubling all resistor and pot resistances and halving all capacitor capacitances will help with reducing signal insertion loss a bit more, while keeping the roll off points about the same)

Title: Re: Tone Stack Calculator
Post by: Jonas on July 29, 2024, 10:38:59 pm

thanks tubeswell - time to get the solder out....