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Knowledge entry · 1984 Out of the Cellar → 1990 Detonator

Warren DeMartini — Jose-modded 1959 Plexi (Ratt era)

Warren DeMartini · Modified Marshall 1959 Super Lead Plexi (Jose-mod chain, no diode pair)

Caveat first: DeMartini's specific Jose-mod chain is *less* publicly documented than Mick Mars's Dr. Feelgood amp or Lynch's JCM800. There's no famous Pete-Thorn-style teardown video, no recreate-thread that converged on a definitive component list. The recipe in JMIL is a best-effort reconstruction based on period interviews, photos of the rig, and forum testimony from techs who worked the Ratt camp. Treat it as DeMartini-*adjacent* rather than a verified verbatim recipe.

What's reasonably certain about the era voicing: - A Jose-modded 1959 SLP (not a 2203 — DeMartini was a Plexi guy through Ratt's commercial peak) - No diode clipping — DeMartini's tone is open, articulate, mid-forward; the diode squash isn't there. Same family as Mick Mars in that respect, but… - Brighter and less compressed than Mars: bright-cap retained (or only mildly reduced), cathode-bypass switched in for the higher-cathode-bypass-cap voicing. - V0 + cascade + Jose MV + NFB tightened — the canonical no-diode Jose chain underneath.

Why the recipe still makes sense as a template even with the citation gap: every documented Jose-1959-no-diode build from the era converges on this approximate component set. DeMartini's tone has the audibly-defining traits of that family (open, articulate, mid-forward, vocal sustain on bends) and lacks the diode-shelf signatures of Lynch or the 12V-zener squash of bedroom Brown Sound. Reasoning from family resemblance.

JMIL surface area: the "Warren DeMartini 1959 (no-diode, articulation)" preset applies V0 + cascade + bright-cap + cathode-bypass + Jose-MV + NFB on a 1959 SLP, no diode pair. Pair with a single-coil-loaded Strat for the canonical voice; humbuckers also work but lose some of the upper-mid articulation that's the preset's whole point.

Friedman rig recall (Amp Panel #8 + #9, Aug-Oct 2025) — significant new detail: - Main amp: a lay-down-transformer 1968 Plexi (canonical EVH-era chassis) with one light extra gain stage added to the front end — NOT the full V0 + cascade Jose treatment. Effectively "an 800 front-end on a Plexi" hybrid. - Running settings: Master at 10, Gain ~6-7, bright cap kicking in at that gain setting. - Stage-volume control: runs into a power station (load-box-style attenuator) for usable volumes. *"in his studio he's using into a power station."* - Marshall borrowed his Plexi for cloning during the 1993 reissue program — the famous "220pF treble-wiper-to-ground cap" in the 1993 1959 reissue (see evh-era-plexi-specs) was added because Marshall was cloning DeMartini's specific Plexi and that cap was in his amp.

This is more specific than the existing JMIL preset suggests — the canonical DeMartini rig is closer to a lightly-Jose'd Plexi (one extra gain stage, no cascade, no diodes) than the full V0+cascade+Jose-MV Brown Sound treatment. Players chasing DeMartini specifically should treat the JMIL preset as a starting point and dial back the gain-staging if they want closer fidelity to his actual rig.

Related mods (6)

  • Extra preamp tube (V0 stage)T1
  • Cascaded V1 → V2 (cold clipper)T1
  • Bright cap reduction / removalT1
  • Cathode-bypass switching (Saturation / Pull-Gain)T1
  • Jose Master Volume (pre-tone-stack)T1
  • NFB resistor change (100k / 4Ω tap)T1

Citations