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DIY Stompboxes => Building your own stompbox => Topic started by: MSR on May 25, 2004, 07:46:08 AM

Title: Valve overdrive pedal??
Post by: MSR on May 25, 2004, 07:46:08 AM
Hi new to the forum

Sorry i'm in one of those creative moods again, Does anyone make a Valve overdrive pedal?
Or how hard would it be to make one? Would it be possible to rip out a valve preamp from a valve amp or buy one, connect up to a power supply, switch and jacks, box it up and done?

thanks for any input
Mike
Title: No....
Post by: sir_modulus on May 25, 2004, 07:56:35 AM
no, as it wouldn't work as most tubes need a B+ voltage of over 120 V. You can starve plate them, but it needs special circuitry. Read here and do not attempt the following until you have a good understanding of tubes and how they work  tube effects. (http://www.zugster.net/amps/articles/tube-pedals/)
Title: Valve overdrive pedal??
Post by: MSR on May 25, 2004, 08:13:44 AM
Thanks
So do you think it'll be better if i got a solid state preamp that'll run off a 9V battery, or just leave it well alone?
Well i'm tryin to make a overdrive stompbox that has a 10band EQ. I can make the EQ easy enough, its just sorting a decent overdrive unit
Title: Valve overdrive pedal??
Post by: sir_modulus on May 25, 2004, 08:20:12 AM
For a preamp with EQ (small) use  practice man  (http://www.generalguitargadgets.com/richardo/practiceamp/practicemaneq.gif)
addmore bands if you wish. for distortion, try fuzzcentral or tonepad. Both have good distortion circuits.
Title: Valve overdrive pedal??
Post by: MSR on May 25, 2004, 08:33:48 AM
I'm going to be using a premade 10band EQ circuit board. and if i can, i'll try to get hold of a premade overdrive circuit board. I have to get them premade as i'm not to handy with a soldering iron
Title: Valve overdrive pedal??
Post by: chumpito on May 25, 2004, 10:26:21 AM
I'm not understanding all this starved tubes sound bad stuff.  From what I understand and if you look at Kevin O'Connor's Power Scaling Kits if you lower the voltage of B+ it scales everything thing down.  So you have to drive it with much less voltage to get the same sound and of course it will output less voltage.
It's like using a Variac with a Marshall except you keep the heater grids at the correct voltage.

I might be the only one, but I think you can take a normal guitar pre and build it stompbox style with lower voltage if you don't slam it's input.