Seeking inspiration for new build

[paggerman]

Hi all, I'm looking for some inspiration and I'm sure you'll be able to help. I've got a piece of old junk that is in beautiful condition. It's a Bruel & Kjaer sound level monitor, but that's not terribly relevant. what is important is that is has a great chassis and case and Power Supply. There must be a dozen valves in there (a lot of which are 7 pin). on the top there is a heap of knobs and switches. I thought about making a multi-effects unit out of it. I've had a look for valve based effects and come up short. I know that there are some 12AX7 distortion pedals around, but can anyone point me in the direction of some valve based effects, please?

Thanks to all.

[Zipslack]

A couple of ideas

You might have already seen this, but there is a project (and VERY lengthy) thread for a project called the Matsumin Valvecaster. This is a low-voltage, starved-plate project for low-medium gain overdrive. There are also modifications of it to make it into a tremolo unit, as well as multiple-stage overdrive variations. Don't know if this is what you're aiming for, but it might provide some ideas.

Beavis Audio Research - original project page

Tube boost + overdrive running off a 9 volt battery - very long discussion forum about the valvecaster-based projects.

I've built the Valvecaster - it's very nice. I have not built the tremolo version, yet...

[mozwell]

Here is one from Freestompboxes.
freestompboxes.org • View topic - BAJA Real Tube Drive pedal project
I have built it, & tested it on the bench, but wont get to listen to it for a few weeks unfotunately.
By all reports this thing is a nice creamy overdrive, & very nice indeed.

Also this one from Merlin B
freestompboxes.org • View topic - Spark Gap

and this one
freestompboxes.org • View topic - 6N16B True tube overdrive with SMPS supply

lots of info at freestompboxes & diystompboxes.

[Zipslack]

Other options...

Also, don't forget complete low-wattage amps like the Firefly. Also, you have the option of building tube-based preamps or tremolos by ripping the relevant sections from existing amp schematics.

Here's a vacuum-tube Theremin - The Free Information Society - Vacuum Tube Theremin Electronic Circuit Schematic

Here's some interesting ideas dealing with synthesizer modules - The Electronic Peasant's Vacuum Tube Synthesizer Page

Here's some stuff that Eric Barbour is involved in - Vacuum Tube Valley and Audio Synthesis via Vacuum Tubes and Audio Synthesis via Vacuum Tubes

How a vacuum-tube wah from R.G. Keen? - http://www.geofex.com/Article_Folder...h/tube-wah.htm

I'm going to guess that some of the OLD texts on vacuum tubes (hi-fi, amp, and general purpose) will probably be your best source of inspiration. A lot of these are available online, but I don't have the links at hand.

[mozwell]

Good reference information here
Professional books : Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics
The complete radiotron valve handbook, and various stompbox & solid state amp books

Also check out freestompboxes.org • View forum - FSB Public Library for downloadable books & reference info, lots of stuff here.