Proco Rat build

Because the 1590BB enclosure is not as high as the 125B enclosures that I normally use (34mm vs 39.5mm), the Switchcraft jack sockets I normally use will not fit along the top edge of the enclosure (won't clear the pots, even mounted between them). As such I had to use the Lumberg Compact type sockets
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Never used these before, & if the pedal was going to be continually plugged/unplugged I would use the Switchcraft sockets mounted on the sides of the enclosure (the Lumbergs look a bit frail). As it'll be just plugged in on my board '& left there I think they'll be fine. Cheers
 
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Almost ready to wire it all up. About 7 more flying leads to be attached to the board. Most of these will travel under the board to where they need to be connected. Controls from left to right (as viewed here from the underside) are distortion, presence, filter & level. Footswitch on the left is effect/bypass (red LED), the one on the right for solo/lead boost (green LED). The positive clipping diode will be mounted on this footswitch. Cheers
 
Ok, here's a gutshot of my new Rat all completed
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Sorry about the poor lighting, the sun was barely up when I took this this morning. The wiring will be tidied up later. I rushed last night to complete it, then tried it on very low volume through a Fender Frontman 15, just to make sure it was all functioning properly, which it does. In my rush though I wired the LED to the boost footswitch improperly, so it's on when operating as a normal Rat & off when the boost is switched on. I'll fix it today by moving one wire to a different position on the footswitch, then tidy it all up. In the little time I spent playing through it I'm really liking the addition of the presence control Sysco. I'll take it out to the rehearsal space (old farm house) later today & try it out through a couple of amps at volume. Cheers
 
syscokid said:
How's the boost working out so far?
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Aside from the indicator LED it's working fine. A good volume boost, not as distorted as normal, but a tighter & more aggressive sound. Lifting the ground on the positive clipping diode leaves only the negative half of the waveform being clipped, pretty much the same as is done by a "cold clipper" in an amp (JCM800 2203/4, Soldano SLO etc, etc).
If you want to try it, lift the ground on the clipping diode that has the cathode (denoted by the band around the body) to ground. Cheers
Edit:
I just remembered that you have the BYOC Rodent which will make doing it a bit different due to the clipping options. You would need to lift the ground on (or temporarily remove) the LED that "does not" have the flat side of the body to ground, & then try it in the LED clipping mode only, probably a bit too much of a hassle to do. Cheers
 
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syscokid said:
Do you still get a volume boost even if the pedal's level control is maxed out?
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I'll have to check that out, I don't usually dime the level control. I'm pretty confident it will still give the same boost though. A standard Rat used 1N914 "hard" clipping diodes. Hard clippers are placed at the output of the amplifying device (between the output & ground). 1N914's clip at about 450~500mV, giving a waveform like this
V__1CDF(1).png
So no matter how large the output from the amplifying device is, it is reduced to the clipping diodes clipping threshold voltage (450~500mV). If we lift the ground on either diode we get a waveform like this
V__1CDF(2).png
(the bottom one is the "negative" clipped waveform) where one half of the waveform remains at the same (clipped) magnitude while the other half is now the full unclipped output of the amplifying device (hence the boost in volume). The "level" control comes directly after the clippers in the Rat circuit. It is simply a voltage divider & as such, outputs a signal amplitude relative to the signal amplitude applied to it, even when turned full up. Apply a small signal to it & it outputs a small signal. Apply a larger signal to it & it will output a large signal. So yes, I believe it will still give a good boost with the level control dimed. Cheers
 
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