Internet forum lore from the early 2000s onward propagated the claim that biasing tube amps hot (high plate current) produces better tone. Per Dave Friedman in Headfirst Amp Panel #9 (October 2025, ~[160:40]):
> *"I feel like this became a thing in the amp community of just guitar players that if you bias the amp hot it was going to be better. I don't know exactly where that came from. Was that EVH when he turned the variac up all the way?"*
Dan Gower: *"It was the rig days, the forums… everyone used to be saying"* hot bias is good.
Friedman: *"Blind leading the blind."*
The actual practice across professional Jose-era and modern boutique work:
- Safe bias range for 6L6/EL34 100W amps: 30–40 mA per tube ([Panel #9 163:12]).
- Anything significantly above 40 mA risks shortened tube life and excess heat dissipation without meaningful tonal payoff.
- Mark Cameron is the documented exception — Friedman concedes Cameron biased some "hot-40s, hot-50s" amps higher than 40 mA for a specific Cameron-school crunch character. Situational, not universal.
Why the myth persists:
1. EVH famously ran his rig through a variac, lowering the AC mains voltage. Players observed his bias was *effectively* hotter relative to lower B+, but the *mechanism* was misinterpreted as "hot bias on stock voltage = good." 2. Some boutique builders started shipping amps biased hot to differentiate them tonally, and forum readers concluded "all amps should be biased hot."
What hot bias actually does:
- Increases idle plate dissipation → more heat, shorter tube life.
- Shifts the operating point — can give slightly more sustain at the cost of headroom and dynamic range.
- Beyond ~80-85% of the tube's maximum plate dissipation rating, the trade-off is essentially all cost, no benefit.
JMIL position: the lab's audio model doesn't expose bias as a user-toggleable control because it's a service-side adjustment, not a tone-shaping mod. Players reconstructing a Jose-school amp on real hardware should bias to manufacturer specs (typically 30-40 mA cold/hot range for matched EL34 / 6L6) rather than chasing the "hot bias = better" forum claim.