"Like" AX84 on facebook

Account Info
Greetings, Guest.

Reset Password
Create New Account

Browser cookies are required for these functions.

Welcome to AX84® the base camp for tube (valve) electronics hobbyists.

AX84 exists to provide:

1) A great environment to learn about music-related electronics in general. AX84 is a place where those with experience are interested in helping diligent beginners who are willing to do their homework.

2) A place where those with more experience can field their ideas to peers and get useful feedback.

3) An environment that respects the past, but is not enslaved by it. INNOVATION IS GOOD (and it didn't die in the 1950s.) There are new things under the sun every day. Move the ball forward!

Our HUGE discussion area is under 'Discussion Forum' to your left.

We are hard at work improving the site- check back often!

Recent Forum Threads
"Adventures in Digital Control"
Posted By Chris Hurley on 10/22/2014
As some of you know, I've been thinking about making an amp or preamp with some amount of digital controls for a while. I certainly enjoy the traditional feel of an amp with regular knobs but I also ...

Discuss this entry
"Mic preamp phantom power"
Posted By DanGu on 10/22/2014
Hi. I'm designing a tube mic preamp (2 channels), and for the power supply I decided to use an hammond 370AX.
So with this transformer I decided to use the 50V bias tap to generate the 48VDC phantom...

Discuss this entry
"Weber-esque 5F4 using '60 Conn Organ Chassis"
Posted By Jonathan Haynes on 10/22/2014
First post here. I come from ham radio kit and homebrew land, and this is my first project. I have several donor electric organs on hand and dove in with a Conn 430 chassis. Looking it over, I saw a 5...

Discuss this entry
"Question about SEL vs Hi-octane"
Posted By Brian CA on 10/22/2014
Hey guys!

I built a Hi-Octane a couple weeks ago and I'm loving it!

I had a question though...when I look at the SEL schematic, I notice R13 and D3, that is not on the Hi-Octane schematic.

I ...

Discuss this entry
"Trouble with ECF80"
Posted By JaapK on 10/22/2014
No matter what I try the ECF80, a small signal pentode and triode in one tube, is giving me trouble: oscillation that is!
Amp is a simple 2 gain stages preamp: pentode ecf80 - volume pot 500k - triod...

Discuss this entry
Like us and Find us

Subscribe to me on YouTube

Updates: Wed, Oct 22nd, 2014 @ 11:26:46
Updates to pages about


have been completed.
Site News

2014-10-21: Be sure to check out our discussion forum using the link on the left..

2014-10-20: The Treasure Fleet is on the way to Rio De La Hacha with a fortune in gold!

We're looking for media clips of recent builds... please stop by the forum and respond to the thread.

2008-10-4: Archived Projects section is functional again.

2008-9-18: RSS Feeds for the forum have been up for a while, but not advertised...
* Active Threads
* New Threads
* Recent Posts

2008-6-26: Want to participate in our discussion forums? You are welcome to read and lurk as you like. If you think you'd like to post with regularity, please sign up for an account.

AX84® is a registered trademark of Doberman Music Products, LLC. AX84.COM content may not be reproduced without the express written consent of Doberman Music Products, LLC (sales@dobermanamps.com).
For information about using the AX84® trademark, project names and designs, click here