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Would you buy this pedal?


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It has an overall gain of about 100, which doesn't sound like a lot compared to some distortion pedals, but keep in mind that depending on the output of your pickups it can actually give close to the full 100 gain WITHOUT clipping, pushing about 40 CLEAN volts p-p before the onset of a little bit of nice and soft asymetrical distortion comes in and about 60 volts p-p before actual clipping, so it can overdrive the input of an amp about the same way a 12ax7 could, but it runs off a 9 volt battery. Most 9 volt pedals can only do about 7-8 volts p-p output, which is only maybe 10-15 times gain before clipping on attack. Almost every booster, by the time you start pushing your amp's input tube, is doing a lot of clipping by itself on the peaks. Input impedance is nice and high to keep pickups bright, 1.5 megaohms. Because of the unbuffered transformer, output impedance is also kind of high, about 25k ohms, but that's actually quite a bit lower than guitar pickups by themselves, so you can plug it into pretty much anything you can plug a guitar into.

 

You can see from the pic that it's a pretty simple circuit, but actually the second stage amp has a fairly sensitively balanced negative feedback loop so that it can properly drive the low impedance side of the transformer, and I have to select the transistors on my curve tracer in order to get the best possible output swing and sound. It would be simpler construction wise to use a buffered opamp, but the single ended fets sound really nice when they start to bend over a little bit.

 

I've been selling them for $150 so far....I should probably try to sell them for more because the transformers aren't really cheap, but it's enough to make it barely worth building them. They don't have fancy pancy paint jobs.transbooster.jpg

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Originally posted by MattCrane

It has an overall gain of about 100, which doesn't sound like a lot compared to some distortion pedals, but keep in mind that depending on the output of your pickups it can actually give close to the full 100 gain WITHOUT clipping, pushing about 40 CLEAN volts p-p before the onset of a little bit of nice and soft asymetrical distortion comes in and about 60 volts p-p before actual clipping, so it can overdrive the input of an amp about the same way a 12ax7 could, but it runs off a 9 volt battery. Most 9 volt pedals can only do about 7-8 volts p-p output, which is only maybe 10-15 times gain before clipping on attack. Almost every booster, by the time you start pushing your amp's input tube, is doing a lot of clipping by itself on the peaks. Input impedance is nice and high to keep pickups bright, 1.5 megaohms. Because of the unbuffered transformer, output impedance is also kind of high, about 25k ohms, but that's actually quite a bit lower than guitar pickups by themselves, so you can plug it into pretty much anything you can plug a guitar into.


You can see from the pic that it's a pretty simple circuit, but actually the second stage amp has a fairly sensitively balanced negative feedback loop so that it can properly drive the low impedance side of the transformer, and I have to select the transistors on my curve tracer in order to get the best possible output swing and sound. It would be simpler construction wise to use a buffered opamp, but the single ended fets sound really nice when they start to bend over a little bit.


I've been selling them for $150 so far....I should probably try to sell them for more because the transformers aren't really cheap, but it's enough to make it barely worth building them. They don't have fancy pancy paint jobs.
transbooster.jpg



Man that's some pretty technical stuff. I'm sure some guy's here will appreciate that discription, but I'm too ignorant to understand what it is you have there. Some kind of groovey overdrive I assume.

How about, what's it sound like and what's it look like?

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