CRATE STEALTH GT50 Lee Jackson

CRATE STEALTH GT50 / GT50-H - CH2 (DISTORTION) PREAMP + TIGHTENING BOOST =================================================== WHAT IT IS ---------- A Neural Amp Modeler capture of the Lee Jackson- designed Crate Stealth GT50 distortion channel (CH2) PREAMP, with a tube-screamer-style tightening boost built into the front. *** Preamp only. NO cab, NO power amp. This is a DI capture. *** Run a guitar DI through it and stack a cab IR after it. Same circuit model as the "Crate Stealth CH2 Preamp" capture (built from the real factory schematic, Crate drawing 07S292-01, reverse- engineered stage by stage in LTspice and dialed in by ear against a recording of a real Stealth), with one thing added ahead of it: - A 2-pole 320 Hz input high-pass, the same low-end trim you'd get from a Tube Screamer / SD-1 set clean in front. It pulls ~3-4 dB out of the sub, tightens palm mutes, sharpens the pick attack and firms up the note edges - without adding its own dirt. (Corner tuned by ear against a real Stealth; fits put it 300-340 Hz.) - Everything downstream is unchanged: V1B 12AX7 -> RC4558 IC1A (freq-shaped, mid-hump voicing) -> IC1B (inverting, 1N746 zener soft-clip) -> GAIN pot -> MPSA13 transistor stage with 1N914 hard clip -> IC2A -> V2B 12AX7 recovery -> Marshall FMV tone stack -> master -> V2A 12AX7 output. - Architecture 2 (A2), trained on the TONE3000 standard sweep through the circuit model. Matches the circuit within ~0.5 dB per band. The Stealth was Lee Jackson's take on a hot-rodded JCM800 - "the tone you get by adding another 12AX7 to a stock 800." This is that, already tightened: fat-but-controlled lows, forward (not scooped) mids, a bright-but-in-check top, medium-high gain. SETTINGS CAPTURED ----------------- The model is one fixed snapshot of the circuit, at these positions (0-10): - GAIN (CH2, dual-gang) ........ 10 (maxed) - VOLUME (CH1 stage) ........... ~6 - BASS ........................ ~7.5 - MID ......................... ~6 - TREBLE ...................... ~5.5 - MASTER ...................... ~6 - Front tightening boost ...... 320 Hz corner Presence and the CH2 voicing switch are not in the capture (post-preamp / power-amp side). Gain is maxed because CH2 is the hot-rod channel; back off with your guitar volume for crunch. RECOMMENDED RIG --------------- 1. THIS NAM. The tightening is already in it - you do NOT need a Tube Screamer in front for low-end control. - Run it RAW (loudness normalize OFF). - Input calibration: +12 dBu (the usual default). Feed a normally-tracked DI at its natural recorded level. It tracks pick dynamics - dig in and it saturates, back off and it cleans up. - Want MORE gain (not more tightness)? Put a distortion / overdrive pedal - or a NAM of one - in front. The capture is chunky enough to sit under a smoother, finer distortion and stay defined. 2. Your usual post EQ / bus chain. DIALING NOTES ------------- - Too tight / want more thump? Use the "Crate Stealth CH2 Preamp" capture instead (same amp, no boost), or a cab IR with more body. - Too raw up top? A darker 57 IR or a gentle high cut around 8-10 kHz. - Responds to pick dynamics and the guitar volume knob - roll it back for crunch. CREDITS ------- - Circuit source: Crate / SLM Electronics factory schematic, drawing 07S292-01 (L. Jackson design; 1992) - Early LiveSPICE traces used to get started: MARKTHERENCE - Circuit modeling, voicing, NAM training: edgiljr5 ===================================================