diyAudio (
-   Tubes / Valves (
-   -   Looking for a fairly simple Hi gain tube pre amp project (

jackasspenguin 31st May 2012 04:00 PM

Looking for a fairly simple Hi gain tube pre amp project
I'm interested in a schematic and or complete plans to build a 12ax7 hi gain tube pre amp for guitar applications. My intentions are to stick something into a small chassis and use as a foot controlled pedal of sorts to drive my Fender Super Reverb made circa 67. I may perhaps build two of them to have a 2 channel clean, and dirty output.

This is my first post here. Hope to enjoy the site!

Merlinb 31st May 2012 04:39 PM

Take a look at the projects at - The Cooperative Tube Guitar Amp Project

Alvis 31st May 2012 04:54 PM

Here's a "Soldano" preamp. Those AX84's don't quite get there.

Soldano Preamp : DIY Fever – Building my own guitars, amps and pedals

Alvis 31st May 2012 04:56 PM


Originally Posted by Merlinb (

lol, are you the "Merlin" mentioned in my link?

SY 31st May 2012 05:00 PM

Although he was too modest to mention it, MerlinB is the author of a book that will answer your question and many more. Highly recommended.

Alvis 31st May 2012 05:21 PM

Too cool.

There are lot's of sound clips for the AX84 HO online and a few sound clips of the Soldano at the bottom of the page I linked.
You can get a pretty good idea to the differences in tone by the videos.

Dragondreams 1st June 2012 07:24 AM

The Real McTube (Fred Nachbaur) might be of interest. I've built a couple of these as pre-amp boosters into my valve guitar amps. They sound great, as well as being a relatively simple build (with a lot of scope for tweaking).

The Real McTube II

Keysy 7th December 2012 03:14 AM

I am no expert and it seems a bit crazy to question anything in the Real McTube but why does he bother to rectify the heater circuit? Can't I just run one secondary of the 12V AC to pin 4 and the other to pin 5/ground to supply the heater?

Dragondreams 7th December 2012 08:04 AM

Hum. ;)

On Fred's page he actually states:
"This results in a significant reduction of AC hum as compared to the original "Real McTube", which used AC to directly heat the tube's filaments."

DF96 7th December 2012 09:41 AM

Instruments & Amps???

All times are GMT. The time now is 05:03 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio