Everything learned while compiling the code tables, written down — including the parts of amp dating that do not work.
Fender kept no amplifier serial records before 1994. Here is the order that works on a vintage Fender: tube chart, transformer, speaker and pot codes.
2026-10-14 ↗Tube chart referenceBoth Fender tube chart cycles, letter by letter: the vintage 1951–1969 alphabet, the 1990–2015 reissue alphabet, and how to tell which one your amp is.
2026-10-14 ↗Component codesHow to read EIA component codes on transformers, speakers and pots: the format, the manufacturer numbers, the decade trap.
2026-10-14 ↗Marshall, five systemsAll five Marshall numbering systems, 1962 to today: year letters, the barcode sticker, M-YYYY-WW and the model numbers that look like years.
2026-10-14 ↗Ampeg, six erasAmpeg published its own serial guide, and it admits two eras cannot be dated. Year digit, month, six-digit ranges, SLM letters and the safety warning.
2026-10-14 ↗Vox, three systemsVox AC30 dating: JMI dated serial points, Thomas Organ year prefixes and the Korg era, where no code was ever published. Three systems that never mix.
2026-10-14 ↗Our methodWhy a component code dates a part and never an amp: the bounds rule, stock lag, post-dated pots and what we refuse to claim about your amplifier.
2026-10-14 ↗Components firstNo serial number, no table? How to date an amp from transformer, speaker, pot and chassis codes, and when a component code cannot help.
2026-10-14 ↗Before you buyFender tube chart cycles, Plexi cosmetics and the reissues that look identical to the original: a pre-purchase checklist for buyers.
2026-10-14 ↗Value, not guessesWe publish no price ranges yet. Here is the method: the five factors that move an amp price, the sold-price rule, and why our data says not collected.
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