Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: kagliostro on December 09, 2022, 12:02:07 pm

Title: Rusty Brain, please need help for this TS layout
Post by: kagliostro on December 09, 2022, 12:02:07 pm

Here are rainy days and my brain is in sofference (not only the brain)

I'm drawing a modified version of the Fender 6G5 Tone Stack (the version Merlin, with changed values, used in his Middle Gain Preamp)

the original has Treble and Bass controls but I want to add also the Middle control

is this a correct layout ?



(https://i.imgur.com/08E0G5U.jpg)


Franco


p.s.: attached the .vsd Visio file

Title: Re: Rusty Brain, please need help for this TS layout
Post by: pdf64 on December 09, 2022, 12:08:59 pm

If the bass control is set low, that middle control will tend to become ineffective.

Title: Re: Rusty Brain, please need help for this TS layout
Post by: kagliostro on December 09, 2022, 12:27:34 pm

Thanks pdf64

So, in your opinion, what is better to do, leave the TS without Middle control or adopt a different TS ?

Thanks

Franco

p.s.: The Layout is correct or wrong ?

Title: Re: Rusty Brain, please need help for this TS layout
Post by: 66Strat on December 09, 2022, 01:16:38 pm

I don't think the layout is correct to do what you want it to do. The 10n capacitor and the wiper lug of the Bass Control pot should connect to the top lug of the Middle Control pot. There should be a jumper wire between the wiper lug and the bottom lug (ground connection) of the Middle Control pot. I would have altered your file to illustrate, but I can't open the .vsd file.

EDIT:

I think a different tone stack may better serve you, if your goal is to add a Mid Control.

Title: Re: Rusty Brain, please need help for this TS layout
Post by: kagliostro on December 09, 2022, 02:18:43 pm

The guy who is swapping a Geloso G1 1020 A from PA amp to Guitar Amp likes controls and so .....


the .vsd file is a Visio 2007 file

Thanks

Franco

Title: Re: Rusty Brain, please need help for this TS layout
Post by: sluckey on December 09, 2022, 02:38:28 pm

I don't see anything special about that 6G5 tonestack. Nor do I see a way to add an effective mid control. That was at a time when Leo was experimenting a lot with tone stacks. I suggest just using the AB763 TMB tonestack. Sounds good, plenty of control with all three pots, and plenty of visio layouts for that.

Title: Re: Rusty Brain, please need help for this TS layout
Post by: kagliostro on December 09, 2022, 03:19:18 pm

Many Thanks Steve

After the answer of pdf66 I was thinking to maintain the two knob TS or to go to one other TS with tree knobs

so I'm glad to you for the suggestion

it will be an AB763 Tone Stack


Do you have an example with components on pot ? The board is small ...

Grazie

Franco

Title: Re: Rusty Brain, please need help for this TS layout
Post by: glass54 on December 09, 2022, 08:19:38 pm

Hi Franco
Try https://robrobinette.com/How_The_TMB_Tone_Stack_Works.htm (https://robrobinette.com/How_The_TMB_Tone_Stack_Works.htm)
I have attached the TMB as well, if this is what you need  :icon_biggrin:
Kind regards
Mirek

Title: Re: Rusty Brain, please need help for this TS layout
Post by: kagliostro on December 10, 2022, 06:32:19 am

Many Thanks glass54

I had that layout but your's is a confirm that it is what I need

Franco