Modding amps

[guitarmike]

I recently bought a Jim Wigle Puplexi. One of the reasons I bought it was to use as a platform for learning how to mod an amp. I have absolutely no desire to go into business or sell anything I do, I just want to tweak it to my taste. I would like to do the following:

1. Add a line out.
2. Tweak the eq, especially when the fourth gain stage is engaged. The fourth gain stage is variable.
3. Add a "Jose" saturation circuit.

I was poking around the internet and Metro forum but need some help getting started. Any ideas?

Thanks!

 

[LP Freak]

Spend some time on the Metro forum. You'll need to do some digging but it's all there.

 

[glip22]

Jose is easy especially if the tone stack is after the tone stack.

 

[dirtyfunkg]

Jose is easy especially if the tone stack is after the tone stack.

Your what hurts?

 

[IndyWS6]

Jose is easy especially if the tone stack is after the tone stack.

Your what hurts?

 

[glip22]

Jose is easy especially if the tone stack is after the tone stack.

Your what hurts?

Master volume

 

[bbaug14]

Do a search on discharging filter caps first. Thank me later.

 

[kurtsstuff]

Jose is easy especially if the tone stack is after the tone stack.

Now thats fuckin funny right there..I don't care who ya are!!

 

[psychodave]

Spend some time on the Metro forum. You'll need to do some digging but it's all there.

Best answer!!

There is a TON of information there.

 

[guitarmike]

Do a search on discharging filter caps first. Thank me later.

Back in the day when hot rodding a car the first thing you did was buy an Accel Super coil. 40,000 volts to the spark plug. I got zapped one time while my dad was watching and he said I looked like a flag on a flagpole.

 

[Jeff Hilligan]

Or buy one of Bruce Egnaters boutiqekits! Great little amp and very easy to mod and experiment with!

 

[PatF]

I would build the line out in an external box and buy the Jensen transformer.

For learning I think it is best to start at the stock 1959 spec. Mess around with jumpering the channels, make the bass channel less muddy, etc. The AC/DC sounding start point.

Exhaust the plexi options. Try the different tone stack values, cathode cap swaps, .1 output coupling caps, the 220K plate resistor on V2, bright caps, '67 filtering and other filtering swaps, etc.

Then add in the 2203 V1 cascade and go through the options again. After that is when I would start messing around with the Jose style added tube stuff.

A lot of eq can be done with the cathode caps and coupling caps between stages.

You can jig up some of this stuff and clip it in without disturbing too much of the existing circuit.