Amp Tech Toolkit

Amp Tech Toolkit puts the calculations and data a guitar amp technician reaches for in one place, with records for every amp on your bench.

TUBES
• Datasheet ratings and bottom-view pinouts for 37 preamp, power and rectifier tubes
• Tube swap checker: direct swap, rebias, only if the amp is designed for it, or not compatible, with the reasons

BIAS & POWER
• Bias calculator: target idle current for any dissipation percentage, and checks of measured readings per tube
• Cathode bias: current, dissipation, resistor and bypass capacitor
• Power supply: B+ estimate, ripple, filter stages and filter-cap discharge time

CIRCUITS
• Tone stack frequency response with knob settings and editable part values
• RC filters: coupling, plate-to-grid, bright cap, cathode bypass, interstage dividers
• Ohm's law, resistor power, series and parallel, voltage dividers
• Resistor colour bands, capacitor codes and standard values

SPEAKERS & SIGNAL
• Speaker load: cabinet impedance, how power splits between speakers, and output tap matching
• Output transformer ratios and reflected loads
• Decibels, volts and watts, and output power across a dummy load
• Tone generator: sine, square, triangle, sawtooth, noise, sweeps and bursts

RECORDS
• Amps with tube complement, output taps, fuses, a bias log with per-tube readings, service log and photos, and a one-page service sheet

Every tool explains itself: a short guide the first time you open it, and ⓘ notes on the fields. Works offline. No account, no ads, no tracking.

Tube amplifiers contain lethal voltages. This app is a reference for trained technicians; check every value against the schematic and data sheets.