Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: octal on February 07, 2015, 08:21:26 pm

Title: plate driven Marshall style tone stack
Post by: octal on February 07, 2015, 08:21:26 pm

I was wondering if it's possible to build a tone stack which has similar response to the standard Marshall 1987X tone stack, but is plate/anode driven. I've seen a few builds where people have used "Marshallish" component values plate driven, but it seems like you'd have to adjust the values to compensate for the much higher output impedance of the plate driven stage VS a cathode follower.

The only computer I can run the tone stack calculator on is currently disassembled or I'd play around with values myself, and I'm thinking this must be a topic which has been addressed before. (I did some searches, got nada.)


TIA

Title: Re: plate driven Marshall style tone stack
Post by: dnator on February 09, 2015, 09:22:20 am

Attached is something I came up with to get a Marshall response with a one knob tone stack using fixed resistors for the bass and mid.
The top line is the cathode follower driven marshall stack.

Title: Re: plate driven Marshall style tone stack
Post by: octal on February 10, 2015, 03:05:21 pm

Thanks! I'll have to tweak the values to get the sweep right, as I'll be using a 3 pot tonestack.  Probably time to drag that XP computer up out of the basement and start playing around with TSC.

Title: Re: plate driven Marshall style tone stack
Post by: SILVERGUN on February 10, 2015, 03:24:16 pm

Just for the record....I'm running Duncan's TSC on Win 7 - 32 bit with no problems.

I'm guessing yours is 64, but just wanted to mention it.

Title: Re: plate driven Marshall style tone stack
Post by: DummyLoad on February 10, 2015, 07:10:34 pm

works on win7 64bit. may exit with an error: not an issue.

--pete

Title: Re: plate driven Marshall style tone stack
Post by: octal on February 10, 2015, 08:25:21 pm

Well, main home computer is a Mac, so I'm SOL on that. I was wondering about installing it on the Win 7 machine at work, but I thought it wouldn't work. Now I know it will. Thanks again.