JHS Pedals Overdrive Preamp

[jeffwhitfield]

I highly doubt this is a complex circuit so shouldn’t take long to trace. It’s a precursor to the DOD 250. Very interested in seeing what this circuit looks like. Sounds interesting.

JHS Pedals, Kansas City USA— Overdrive Preamp

www.jhspedals.info

 

[spi]

What's your DMM's test current?

1ma according to manual

 

[Chuck D. Bones]

The best advice I can give re: diodes is socket them and find out which ones you like in that particular circuit.

Diodes that sound good in a Distortion+ may or may not sound good in a Klon, Rat, BMP, TS, DS-1, Bluesbreaker, Tone Machine, Chrysalis, Emerald Green Distortion Machine, etc.

Don't believe everything you read on tagboardeffects.

 

[phi1]

250 / dist+ seems like a good simple platform to experiment with stuff like this. One of the configurations he mentions the dist+ type.

AMZ Saturation Controls and Diode Clipping

Expanding the Tone of Diode Clipping with unique saturation controls.

www.muzique.com

 

[Chuck D. Bones]

1ma according to manual

Your DMM measurements agree with the curves I posted above.

Some DMMs measure at 5mA or higher. If the manual doesn't say, you can always measure the test current with another DMM.

 

[music6000]

Black & Tan Limited Edition:

 

[cdwillis]

Wait, that is real?

 

[Chuck D. Bones]

Ya never know with Phill. His Photoshop skills are that good.

PRETTY!

 

[music6000]

Wait, that is real?

It was a request from the Beer Drinkers!
Stick your Mouse pointer on the Picture!

 

[Chuck D. Bones]

Something else to keep in mind is that the diodes are not the only source of distortion. Driving the opamp to saturation is the primary source of distortion. The diodes provide additional compression and control the tone at the tail end of the note decay.

 

[TheHammer1982]

I have three JHS pedals, a 3-series reverb, 3-series delay, and a Bender. I took the Bender apart and wasn’t impressed at all, especially for the $180 I paid for it. I’m probably going to sell it and build something to replace it. Glad I didn’t buy the overdrive preamp since it appears to be nothing special at all.

 

[Chuck D. Bones]

"Why buy when you can build?"

Seems to be the common wisdom 'round these parts.

 

[jimilee]

"Why buy when you can build?"

Seems to be the common wisdom 'round these parts.

True. I’ve started collecting pedals here and there, but generally I build mostly.

 

[jeffwhitfield]

I have three JHS pedals, a 3-series reverb, 3-series delay, and a Bender. I took the Bender apart and wasn’t impressed at all, especially for the $180 I paid for it. I’m probably going to sell it and build something to replace it. Glad I didn’t buy the overdrive preamp since it appears to be nothing special at all.

Yes, it’s nothing special. I gave up even trying to trace it and returned the pedal. If you want a 250 then just go get a 250…or build one.

 

[TheHammer1982]

Yes, it’s nothing special. I gave up even trying to trace it and returned the pedal. If you want a 250 then just go get a 250…or build one.

I ended up building an Aphelion with BAT41 instead of Ge transistors and used 250 values where applicable. It’s sounds great.

 

[Chuck D. Bones]

I ended up building an Aphelion with BAT41 instead of Ge transistors and used 250 values where applicable. It’s sounds great.

Are you talking about the Spaceman Aphelion?

 

[jeffwhitfield]

Are you talking about the Spaceman Aphelion?

Nah. AionFX Aphelion. It’s a platform for the Distortion+ and 250. Pretty good board really.

 

[jimilee]

Hopefully my EQD inspired PCBs will be in this week.