This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.

Tuesday, December 12, 2017

Green Citrus

Here's a cool DIY design of a Green (Mutamp) amp emulator. Four JFET stages with a 2-band EQ and a Boost control. Should be a nice easy fit in a 125B with the board mounted pots. Here's the schematic for reference. Sound demo here.

11 comments:

  1. This can be tagged verified. Built it on perf and it fired up straight away. After biasing the jfets, this thing is killer

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  2. Is there any way to use it as a head?

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    Replies
    1. It's really just a drive circuit. You could run it as a preamp I guess, but you'd need to integrate it with some sort of power amp to make a head. It'd be a pretty one trick pony though.

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    2. Si puedes, sólo tienes que hacer lo que te dicen arriba. Eso o conectar la salida del pedal en el "return" del cabezal que estás usando, así puenteas el preamp que traiga de fábrica y sólo utilizar la etapa de poder.

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  3. The jfets are drawn backwards, with the flat side of the TO92 package facing the wrong way. "G", "S", and "D" are shown in the right place though.

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  4. What Green amps is this emulated from exactly?

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  5. I just built this and holy crap it sounds nice! If anyone is considering this, I'd highly recommend it

    Here's a sample of me noodling with Green Citrus connected to TPA3118 amp module directly to the speaker: https://www.youtube.com/watch?v=zTSK4pB1ySA

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  6. Can anyone tell me why this and several other layouts for the Green amp have a linear Bass pot, but the amp schematics and typical James EQ all show Log pots? I'm getting a ton of bass through this pedal (Fuzz Dogs PCB version) and after looking at the parts and referencing other schematics, it seems like some have log bass, other linear bass, but the amp schems are always log. When I put all the values in to Tone Stack Calculator with a linear bass knob, at noon, it shows a big 10db bass boost. You would have to turn the bass down almost all the way to get it to level out, which sounds like how it's reacting for my pedal as well. Curious to hear any insight on this, I'm far from an electrical engineer.
    Thanks!

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  7. Can I replace J201(Q3-4) with 5457 J-FETs?

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