Tone stack question

[randalp3000]

So I'm thinking of doing a Top Boost circuit without being driven by a cathode follower and doing it plate driven instead saving a gain stage. It will be gain stage, volume, gain stage, tone stack, pi.

Before I tear something apart and do a test circuit can anyone give me some idea what to expect.

thanks
rp

[Reeltarded]

You will particularly like the difference, my prediction. It relaxes everything a little for an easier middle clean kind of thing with the output set higher. You can goof with the slope and mid cap to get it rawkin'!

[JoeCon]

rp

Wouldn't it be better to go Gain, Tone/Vol, Gain, PI??
The volume and tone stack still plate driven but you've got a gain stage after to recover loses thru tone and volume and enuff to drive the PI.

Just wondering if coming out of the tone stack into the PI is gonna be enuff drive...

Thanks.

[roberto]

From some similar experiencies you'll face:
- less midrange harmonics/compression
- a different behaviour of the tonestack

It will be quite a different amp.

[iknowjohnny]

Yeah, it will be quite different. I noticed less harmonic complexity overall and it doesn't have the mids that give it body. So it's sorta fender like i guess you could say. I made mine switchable. It's a marshall style amp. I liked it at first, but before long i found myself going to the CF more and more and in time i just left it there and finally when i realized the CF driven stack was just richer and juicier i took the switch out altogether and went back to a CF driven stack permanently. not saying you will, but it all depends on what you are after. I think if you aren't trying to turn a marshall/vox type amp into a fender you probably won't like it as much, tho at first you probably will appreciate the change. I think if you have a marshall/vox type amp ion the first place you aren't looking to lean towards fender or you would have bought/built a fender. Just MO.

[Firestorm]

It's not only the effect of different source impedances driving the stack; the CF itself generates a lot of tonal character on its own, so omitting it changes apples to oranges.

[randalp3000]

Thanks for the reply's gentleman. IKJohnny, I ran across your thread from awhile back and it got my hopes up.

I've been kinda liking the Fender tone stack lately so I might try it with el84's and see how it feels/sounds. I already have a 2 channel TB amp with an EF86 channel that I might switch to a parallel triode.

thanks again and this was what I was thinking but I'll change it up.

[roberto]

the CF itself generates a lot of tonal character on its own.

absolutely, and expecially that configuration with low voltage supply, Rp=100k Rk=1k5 and the CF with 56k to ground. Well, it was designed just to react that way.

[Reeltarded]

Yes. Midrange character. Our buddy likes it clean. He'll like it.

Dood, Hook it up. You will like it for playing loudish.

[randalp3000]

Yes. Midrange character. Our buddy likes it clean. He'll like it.

Dood, Hook it up. You will like it for playing loudish.

thanks, someone remembered I likes it loud and clean.

I've got my old 2 ch Top boost/ef86 tubed and cabbed up for church this Sunday to see If I like it again.