About · Transparency
Data & model quality
339 datasheets · sources, confidence tiers, SPICE model versions.
Live quality status
Regenerated on every build from the repository data. Snapshot below: 5/29/2026, 8:14:27 PM.
Pd ≤ Pa_max guard
Cross-engine consensus (≥2 SPICE models per tube)
Diverging tubes: 5842 (±79%) · 5998 (±43%) · 6336A (±32%) · AD1 (±96%) · CK6336A (±32%) · EC86 (±58%)
SPICE entries per engine
SPICE bibliography
Each engine implements a published SPICE topology. Canonical sources:
- Ayumi 11-parameter polynomial — Ayumi Nakabayashi, "A SPICE Model for Vacuum-Tube Amplifiers" 2014–2018
- Ayumi 11-parameter polynomial (pentode mode) — Ayumi Nakabayashi 2018
- Adrian Immler q3 (cube) triode — A. Immler, "Improved SPICE models for triode tubes" 2015
- Pieter van der Bijl triode — P. van der Bijl, DIY Audio Forum 2007
- Cohen-Hélie triode (Koren extension) — I. Cohen & T. Hélie, DAFx-10 conference 2010
- Dempwolf-Zölzer 2-form triode — K. Dempwolf, U. Zölzer, "A physically-motivated triode model for circuit simulations" DAFx-11 2011
- Sjursen triode — A. Sjursen, modified Koren with cathode bias, 2018
- Cardarilli polynomial triode — Cardarilli, Re, Bisegna, "Triode model based on polynomial fitting" 2008
- Broyde triode — F. Broyde, DIY Audio Forum
- Duncan Amps DCA-PRO triode — Duncan Munro, Duncan Amps simulator
- Rydel TRIO 1/2/3 triode — Rydel & Krzysztofik, modified plate-current law
- Leach triode — W. Marshall Leach Jr., "SPICE model for vacuum-tube triode" 1995
- Norman Koren triode — N. Koren, "Improved Vacuum-Tube Models for SPICE Simulations" 1996, AudioXpress
- Norman Koren pentode (extended) — N. Koren 1996; pentode extension by various authors
Confidence tiers (A / B / C)
- A — manufacturer datasheet available AND a validated Koren SPICE model exists for the tube.
- B — at least one of the two is available (datasheet OR SPICE model).
- C — no authenticated datasheet, no SPICE model: validate before any design use.
The tier is computed automatically from the data present for each tube and shown in the TrustRibbon at the top of the fiche.
Primary sources
- Manufacturer datasheets: RCA, GE, Mullard, Telefunken, Sylvania, Philips, Siemens, Tung-Sol.
- Koren SPICE models: parameters derived from original plate curves (Norman Koren method).
- Community: Frank Philipse Tube Pages, Duncan Amps, Ayumi Lab — used for cross-checks, never as a sole source.
SPICE model limitations
Koren models accurately reproduce small-signal behaviour and classic operating regions. They may diverge in deep saturation, positive-grid operation, or for tubes with significant manufacturer-to-manufacturer dispersion. Any simulation should be cross-checked against a real prototype before final design.
Correction policy
If you spot a mismatch between an Amperatubes fiche and the original datasheet, or any other technical error, we commit to reviewing and processing the report according to the rules below.
1. How to report
- Email: jmfalligan@gmail.com (subject "Amperatubes — correction").
- GitHub issue (public repository): github.com/jmfalligan/ampera/issues/new — for verifiable corrections that warrant a public trail.
- "BetaFeedback" button on every tube fiche — for short contextual remarks.
2. Target turnaround
Target: 7 business days for a first acknowledgement and a decision on next steps (immediate correction, request for more information, or reasoned decline). Provisional — to be confirmed by the project owner; no contractual commitment is made at this stage.
3. Validation procedure
- Verification of the primary source cited in the report (OEM datasheet, reference manual).
- Cross-check against the other canonical sources (RCA RC-21, Mullard, Philips ECG, Tung-Sol).
- If confirmed, the correction goes through a signed maintainer commit (Jean-Michel Falligan Devergne) with an explicit "fix(data): …" message.
- The Vercel deployment regenerates the site and the sitemap updates the JSON-LD `dateModified` of the affected fiche.
4. Correction log
All content corrections are traced in the public git history of the repository. PRs tagged correction or fix(data) form the human-readable log: github.com/jmfalligan/ampera (label correction).
5. Traceability commitment
Every published correction updates the `dateModified` field of the JSON-LD on the affected fiche (TechArticle, DefinedTerm) and the `lastmod` of the matching sitemap entry. Sources are systematically listed at the bottom of each tube fiche.
Jean-Michel Falligan Devergne
Amperatubes is built and maintained by Jean-Michel Falligan Devergne (JMF) — Paris-based Direction Artistique senior, AI-native operator and lifelong audio specialist. The site reflects two decades of hands-on work with vacuum-tube electronics: building single-ended triode amplifiers, measuring NOS stock, restoring vintage radio gear, and simulating tube circuits in SPICE.
Every datasheet, equivalent, pinout and SPICE model on Amperatubes is cross-referenced against primary sources — RCA RC-21, Mullard Application Reports, Philips ECG tube catalogs, Tung-Sol and Sylvania engineering bulletins — and audited against the canonical references (Frank Philipse's pocnet.net, Norman Koren's SPICE work, Merlin Blencowe's books, Morgan Jones' Valve Amplifiers). The full sourcing protocol lives at /methodology/, and per-tube discrepancies are flagged in the data quality report.
The interactive calculators (loadline, SPICE tone-stack, output transformer load matching) are not generic plotting widgets — they encode the actual design rules used on real builds, with sensible defaults pre-loaded for 339 audio tubes. The 3D viewer renders per-tube geometries digitised from physical samples in the studio.
The site is open source, free, ad-free, no signup, no tracking beyond aggregate Vercel Analytics. Email and contact form below.