1 tube - tube booster for guitar....

I need a very simple design for a 1 tube ( 12ax7 ) booster - starved plate.

and is it possible to have it run off of 9v. so that i could easily incorporate into my pedal board?

thanks for any replies.... :grin:

Have considered the low voltage Space Charge Tubes? or are you set on using 12AX7?

[quote author="skipwave"]Have considered the low voltage Space Charge Tubes? or are you set on using 12AX7?[/quote]

thanks for the reply:

well, not really "set" on the 12ax7, but i have alot of them and a 9 pin socket i'd like to use.... and would love to build a simple booster...

also would like to keep the amperage low....at around 200 ma.

Here's a more pertinent link:
http://www.diystompboxes.com/sboxindex.php?topic=22194

Pulled from this thread:
http://www.groupdiy.com/index.php?topic=1195

I wonder how the 12U7 section of the Sopht amp would sound on it's own, without the 12K5 driver.
http://www.sopht.ca/index.php?s=26

thanks....

If you are liking the idea of a low volt tube, you could get more gain out of the high-mu triode half of a 12aj6 and save on heater current compared to the 12u7.

http://www.nj7p.org/Tube1.php?tube=12AJ6

Then again, if you want some distortion with your boost, you would likely get that from the first stage of the 12u7 smacking the second grid.

On the other hand, if you want to use a 12AX7, because like me you have piles of them, the TubeWorks BlueTube pedal always sounded good to me. I think I have a schemo for it somewhere. I'll see if I can find it.

You could fit an acorn tube, or miniature in the guitar cavity if you wanted to be the first kid on the block to own a Neumann power boosted git fiddle.
Coulfd you get jiggy with that, or would the ectra conductor in the guiotar cable bother you?

Probably the Real Tube or Blue Tube pedals are your answer. Can be cloned. I also saw they've become quite cheap (now in all aspects ! :wink: )

Tube Works 901 Real Tube Overdrive Pedal



These are using an internal mains-TX, but that could be a wall-wart as well. Uses a single 12AX7 and some opamps. You could skip the tonestack if you want, but it's good to be able to EQ the boosted mode.

BTW, the Blue incarnation has about the same topology but less gain.

[quote author="CJ"]You could fit an acorn tube, or miniature in the guitar cavity if you wanted to be the first kid on the block to own a Neumann power boosted git fiddle.
Coulfd you get jiggy with that, or would the ectra conductor in the guiotar cable bother you?[/quote]

that would be totally awesome sweet DUDE!

well - how about a nuvistor based booster?

I build the ron black distorcion, a starved plate tube distorcion . it was my second diy project a looooong time ago. and never work .

I have one of those. It's been sitting around for years because I never liked the way it sounded. Anyone wanna buy it? :wink:

[quote author="NewYorkDave"]. Anyone wanna buy it? :wink:[/quote]

No thanks :wink: but I mean, I already have one AND a backup. [i]Despite[/i] some 'technical vices' (like polarity inversion between bypassed & enabled, some hum, not-foolproof FS-button) I've been using this pedal for years. It has something going for it.
I used it for [b]elec.bass [/b]but at very [i]modest [/i]gain settings, with & without a dry-signal blend. Enabled 100% of the time.

It does rob some bottom (as most overdrives 'need' to do), but I have added an on-off-on DPDT for some corner-frequency switching. Believe it or not, despite the tubes that are already in my bass-pre this box made the difference for me. (Adjust to taste) Must say though that both units I have are not completely alike in sound, so very well those boxes can sound not-yet while the next one is just-it etc.

[quote author="NewYorkDave"]

I have one of those. It's been sitting around for years because I never liked the way it sounded. Anyone wanna buy it? :wink:[/quote]

trade?

[quote author="NewYorkDave"]

I have one of those. It's been sitting around for years because I never liked the way it sounded. Anyone wanna buy it? :wink:[/quote]

price?

Look what i found!

http://aronnelson.com/gallery/vanhansen/marshavalve_tube_0

but will it work?

Build it and find out

im going to breadboard it.....ill post a reply as to the progress.

[quote author="Gus"]Build it and find out[/quote]

that's my intentions...just wanted to see if there was any visible problems.

[quote author="Lo-Fi"]Look what i found!

http://aronnelson.com/gallery/vanhansen/marshavalve_tube_0

but will it work?[/quote]

That's almost too easy. :wink: I should slap one of these together, too. I certainly have all the parts, but I still want to make a 12aj6 or 12u7 booster.

Edit: What I don't understand about these starved plate designs is the voltage drop across the plate resistor. At 1.2ma plate current through a 100k R that's a 120V drop. How does that work when you only feed it 12V?