The ToobMOS 30W Guitar Amplifier PUBLIC

The "ToobMOS" 30W Guitar-Amp Circuit by Kurtus Richter

The "ToobMOS" 30W RMS guitar amplifier circuit. Solid-state circuit designed to sound like a tube-amp using JFET-input op-amps and a MOSFET power-output section. Controls Include: Gain, Tone, Trim, Feedback, and Line-Out Volume. Provides 30W RMS clean into an 8-ohm speaker, or 36W distorted.
The input can be overdriven to produce tube-like JFET distortion, and the MOSFETs can be overdriven by the op-amps, depending on control settings. Frequency Range 22 Hz to 20 kHz with all controls at 50%, or 16 Hz to 33 kHz with all controls at 100%. Suitable for 6/7/8-string guitar or 4/5/6-string bass. Maximum Gain = +29.3 dBV (Vi/Vo = 29) @ 400 Hz with all controls at 50%, or +39 dBV (Vi/Vo ~ 100) @ 400 Hz with all controls at 100%. The Gain control boosts overall gain by +6 dBV when at 100% with all other controls at 50%, but can also cut volume to 0 regardless of other control settings. The Tone control has little effect when > 50% but cuts gain significantly and pulls high-limit down to 10 kHz when set at 0% (yet also boosts upper-mids at that setting). The Trim control has no effect on gain or range but effects the bias of OA2. Adjust for least noise. The Feedback control can boost overall gain by +4 dBV, but can also cut volume to 0. There is additionally a Line Out with its own Volume control. It does not affect circuit gain or range but has a gain of its own of +11 dBV at 50%, or +17 dBV at 100%, with all other controls at 50%, while its range is 40 Hz to 10 kHz. Power-supplies not shown. Example Regulated Off-The-Shelf Supplies: Op-Amp Supply; Bel HAD12-0.4-AG, +-12VDC, 400 mA; DigiKey # 179-2305-ND, 169.75 dollars US. MOSFET Supply; Bel HCC24-2.4-AG, +-24VDC, 2.4 A; DigiKey # 179-2329-ND, 322.41 dollars US. https://www.digikey.com . Example Speaker: Celestion "Midnight 60" guitar speaker, 12", 60W, 8-ohm, from Parts Express, part # 294-1984, 99.00 dollars US. https://www.parts-express.com . And though simulator verified, treat the circuit as experimental. Thoroughly breadboard test before committing to a soldered build.