Vacuum tube reference & design toolkit
Amperatubes — 339 tubes · 286 SPICE models · 14 engines · 55 guides
The most complete vacuum tube design toolkit on the web.
STAGE 01 · GAIN
Every tube has a voice.
Drag the Q-point across the plate characteristic curves and watch power, distortion, and gain respond in real time. 286 SPICE models ready for simulation.
STAGE 02 · TOPOLOGY
Stage Designer
End-to-end design wizard for every classic tube amplifier stage. Pick a topology, select your tube, set operating conditions — get a complete design with schematics, component values, and performance predictions.
- 11 topologies
- RDH4 · Reich · Terman formulas
- E24 resistor snapping
Select a topology — the schematic redraws.
STAGE 03 · MODEL
14 engines. 286 models.
Not just Koren — the world's most diverse vacuum tube SPICE library. Cross-validated across engines with consensus scoring. Download .subckt files for LTspice and ngspice.
TRY THE CALCULATOR →STAGE 04 · COMMAND
One palette. Everything.
Tubes, guides, glossary, topologies, manufacturers — searchable by alias, by filter, by natural language. Four corpora indexed. The fastest way to anything on Ampera.
- Semantic ranking — "warm preamp triode" finds 12AX7
- Inline filters: type:triode mu>50 maker:mullard
- Compare basket — pin tubes, fire /compare
THE COLLECTION
339 Vacuum Tubes
From octal-base power triodes to miniature noval preamp tubes — each entry includes full electrical specifications, pinout diagrams, sonic character descriptions, operating presets, and SPICE model parameters where available.
FULL CATALOG
The rest of the bench.
Encyclopedias, learning paths, pro tools, a century of history — everything below is one click deep.
Start designing.
339 tubes · 286 SPICE models · 55 guides · Free & open
Independent technical companion — always cross-check with official datasheets