Amplifiers:Pass Labs 5FT

NameF5Turbo Power Amplifier
Approx Cost$xxxxx
TypePush/Pull Class A
DesignerNelson Pass


Specifications

NameDescription
Volatge Gainxxxx dB
Bandwidthxxx
Phasexxx
Output PowerF-5T v2 - 50 Watts per channel into 8ohm
F-5T v3 monoblock - 100 Watts into 8ohm
S/N Ratio
xxxx
Rated Consumptionxxxx
Idle Consumptionxxxx
Output Impedancexxxx

Intro

This page is under active construction as of 9/2020.
I'll be cribbing most material from 6L6's excellent Illustrated Build Guide. Once I start getting into my own build, I may swap out some pictures and details with my own experience.
Even this introduction is going to go away. Authors waxing-poetic doesn't age well, and the audience just wants the goods.
At the time of this writing, 9/2020, the wiki image system seems busted. I've been using imgur for years, so I'll do that again here to make it work.

Schematic/Blueprint


There is one error in this schematic - R26 should be 10K

Also, in my opinion, C3 and C4, labeled here as ‘OPT’, are required for stability from destructive oscillation. This is a very high bandwidth design and those caps help protect it from ultrasonic HF oscillation. Use 1000pF. Also, if oscillation is a problem for your build, increase the value of the gate resistors (R13 -16 and similar) any value from 47.5R to 680R will work and sound fine, the higher the value the more damping occurs.

Bill of Materials

PCB $49 diyaudiostore

Enclosures
Recommended enclosure is the diyaudio 5U $499. Includes: heat-sinks, screws, and many other things you'll need.
height 210mm, width 360mm, depth 400mm. height 8 1/4in x width 14 1/4in

Heat sinks
Included with diyaudio 5U above: Two 40mm thick x 200mm deep

Simulations and Analysis

xxxx

References

Firstwatt F5 article, Nelson Pass
F5 Manual PDF, Pass talks about this manual as required reading before attempting this build
F5 Turbo Power Amp PDF, Nelson Pass

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