Unfortunatly, no THD improvement...

If you want less gain:
* Like elrengofa, you can put his Jfet references.
* But if you have already the J201, you can decrease 2x Resistors which set the gain of the 2 stages:
- 1st Stage T1/T2: R5= 22 Kohm like Medved schematic
- 2sd Stage T3/T4: R8 from 3M to approx 220K depending your taste !

To meffcio: 9Vdc power supply compatibility, - You could try to replace the four R1, R3, R10, R11 by four Diodes 1N4148 which keep the bias source at # 0.7Vdc regardless the power supply. Also, with these kind of jFET, the iBias should be approx the same, and the lower Vds is not a problem for smoot...

Hello ! - I am impressed by this schematic ! :shock: - If it is not too late, i would appreciate if Bajaman could email me the AES2004 paper of Dimitri (Hello !), to improve my knowledge ! :) - I made some Spice simulations & Proto of Jfet cascode, ActiveLoad etc.. but i never saw that (about Ao...

Seems super schematic ! :D (Also Jfet KP303-A # 2N5953, J113 # BF245-A) I made only the first Stage T1/T2 with 5spice simulation, and it "overdrive" very smooth ! Agree, the close match is not mandatory, as the DC gain T1/T2 is unity. I saw it with Jack Orman "Booster 2.5" 2x Sta...

Hello ! Tremolo background noise, with the link you provided: http://www.moosapotamus.net/IDEAS/stompboxology/Vol4No4/Page_04.gif I regarded the AppNote (from mictester), and something is strange about this schematic about the IC3 NE570: it as pin 2 & 15= left open NC :scratch: ! As it is the 2x...

Maybe the results would have been better without any smoothing capacitor (feeding the audio signal to the rectifier input) ? analogguru Certainly yes ! NE570: As mictester said, soggybag has a original idea to use a NE570 for a tremolo ! BTW, I did not know that the THD trimPot (pin8), decreased al...

The device seems to produce considerable distortion: 1. The very first stage has too much gain to process the guitar attack without severe clipping 2. The BJT "shunt" usually begins to distort signal at approx. 0,6 Volts peak-to-peak. So, those two factors should introduce considerable no...

Re Hello !
I made a mistake on my first post about the "Layout PCB" picture
Here under the good one !

Hello ! Its also my first post ! :) Here under some info about my BlackFinger i bought in 1980: Schematic: https://img682.imageshack.us/img682/3643/bfingersch.th.jpg Curve i/o Comp: https://img9.imageshack.us/img9/3641/bfingcompcurv.th.jpg Layout from "PCB": https://img682.imageshack.us/im...