Hoffman Amplifiers Tube Amplifier Forum
Other Stuff => Effects => Topic started by: lkrasner on September 11, 2015, 08:08:12 am
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I'm trying to plan some kind of interesting tube overdrive/ boost pedal and I'm looking for some inspiration. Here's what I'm thinking so far:
Powered by a real high voltage supply (probably with that 12V to 240V step up transformer)
2 tubes (or possibly 1 dual triode), first gain stage to boost the signal up enough to overdrive a second stage considerably
"volume" control between stages to control overdrive, and another after everything to control the output volume/ boost level
I want to do something different, not the typical dual 12a_7 setup. Perhaps use a pentode for the overdrive stage like was used in many early amps (fender champ comes to mind)
I'm open to any ideas, I just started brainstorming this while sitting in a calculus lecture this morning.
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The high V. might only be good if you want clean also, like 2 channel. good dirt sounds abound from 9volts to 150 to? but the cleans really shine in high voltage. or maybe clean, dirty, dirtier, on floor, that you can mess with knobs with feet, and power amp/spkr in back-line.
don't know if it would be noisy with shielded cord. A lot of stages have rattle that transmits through cord. maybe LowZ out?
will it run to normal amp input, what kind? and I bet a good strong chassis is good start with thought toward shielding properties, and I always figured the best reason for having pedals is you can change params with feet--more dirt, less dirt, seamless, ramp up or down style, instead of abrupt like a switch. I use those rubber knob MXR thingies to help with foot 'shifting' and have seen some pro cats that have had roadie actually put an arm/paddle on/in place of key knobs to help with 'on the fly' changes.
maybe fx out in between pre-amp stages...? good luck,,, been thinking about same
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I'd like it to be fairly universal - not built for a specific amp, but the idea would be to put it into a clean channel, or cleaner amp and let the pedal do the work. Some of the clean blackface fenders sound fantastic when you give them some boost and overdrive them a bit, so I'd like to be able to do that, then turn it up to get nice and crunchy. Not fuzz level, but cranked lead channel level.
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http://el34world.com/schematics.htm#Tube_pre_amp_in_a_pedal_box_ (http://el34world.com/schematics.htm#Tube_pre_amp_in_a_pedal_box_)
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http://el34world.com/schematics.htm#Tube_pre_amp_in_a_pedal_box_ (http://el34world.com/schematics.htm#Tube_pre_amp_in_a_pedal_box_)
"It is a pre amp that I used for recording.
It is not a stomp box distortion pedal."
That sounds like the opposite of what I am looking to do...
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Sorry, figured it would act as an overdrive, since it would basically be a gain stage in front of the first input valve.
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That would make a nice overdrive pedal when plugged into the input jack of a guitar amp. That's not how Doug was using it.
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I like my Mesa Boogie V1 Bottle Rocket. (It is a tad noisy -- hiss). Anyway it might give some ideas. I put orange drops in the signal path. It has a high quality PC board with eyelet connections! Mesa Boogie sent me the schematics, parts list, etc. for free.