MIG-LR/S Tube Preamp for Transistor Leslies

The MIG-L Leslie Tube Overdrive worked with a real tube. It can be mounted on your Leslie's active crossover circuit board with two screws and four wires.

Due to quality issues (microphonic effects) on late russian surplus tubes available on the market today, the MIG-LR tube preamp is no longer available by KeyboardPartner. I don't have any parts or PCBs left. But if you happen to get one of these tubes, you can make your own MIG-LR by etching a PCB and soldering your own parts. Tubes 1SH18b (1J18b) and 1SH24b (1J24b) may be used; choose anode resistor (22kOhms to 47kOhms) to yield anode voltage of 12 to 15 V on 28V power supply. ICs used are CMOS logic types CD4066 and CD4069 (best sounding are made by Phillips/NXP).

Complete description (old KeyboardPartner site)

Dokumentation/Installation Manual - Download als PDF

(english) Documentation/Installation Manual - Download as PDF

Latest version, schematics PDF

Latest version, layout PDF

Latest version, silk/parts placement PDF

Russian tube datasheets are available here

Please note: Permission granted for private use only, commercial use prohibited. (c) by C. Meyer 2005.