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Yep, it wont make any difference

I’d try to replace the input diode (1n5817) with a 100r resistor and add a 100uf in parallel with the existing 47u, if possible. Or just replace the wire from your dc jack to the + pad (1n5817) with a 100r and see if its better

Right, of course! Thanks

I wonder if he's using the 500k pot as a voltage divider (like a standard volume pot) or as a resistor to ground (like the echoplex does). Also with 1N5817 the charge pump should output around 26v I believe, not 22v. Curious to see the schematics :)

Wow thats beautiful!

Usually I prefer to bias at 2/3, and I remember an Echoplex schematic that showed a bit more than 14v for the jfet. But it shouldnt make any difference :)

Very nice!! Any chance to see the schematics @caiofilipini ? :)

As long as you get about 4v on both transistors (Q2 and Q3), you shouldn't worry about it.

If I remember correctly Q1 should be biased at 5.1v (I'd trust that voltage instead of the 2k resistance) and Q2/Q3 at 4v. I use a 50k trimpot for Q1 and 100k trimpots for Q2/Q3. Maybe try a 100k for Q2 and see if you can bias it at 4v. I don't understand "Q3 seemed weaker than it should be".

Also if in Europe, Musikding or Uk-electronic.de have them!

Totally agree. But when I sell Rat based pedals, customers usually prefer to get a LM308 instead of a OP07 in it... To my ears, it doesn't make any difference, and I tested the two chips quite extensively! But I really like the LM301 too. Might have to build another Rat with an LM301 soon :)

Nope but if I remember correctly I used a LM301 a while ago with excellent results! They’re easier to find than LM308

Great, good job!

Just making sure and trying to help, relax man. I did ask about the voltages too but you chose to ignore that. Oh well, good luck with your build then.

Did you check the continuity between the smd transistor lugs and the pads on the little adaptor boards? Also voltages would be good to have yes

Yeah, I thought so. I keep buying LM308 from good dealers, but when I compared one to an OP07 some years ago, I found almost no difference in tone. But real LM308 are harder and harder to find.

Nope they’re 0.5% tolerance In the same idea, I’ve thought about faking LM308 with recased OP07 for Rats, wondering how much it’d cost to do that, and if it already exists :)

Old build documents for the Paragon still showed 10n for input caps. 22n makes a difference. Check what value you used. Also how did you set the internal trimpots?

thanks a lot, I’ll keep using the Ruetz mod then as I really like the lower drive tones it offers. Thanks again !

Just came accross your post, thanks for sharing! I imagine it sounds about the same as the Ruetz mod (adding a 1k pot between R7 and C9), am I right?