Previously Featured Builds

build

Gregor Doler

Gregor Doler

This is my first Class A amplifier ever. I was always more into AB class amplifiers, because of smaller power… More...
build

Elliott Wolf

Elliott Wolf

This was my first attempt at building an amplifier, or anything even remotely similar. Before building this, I built an… More...

Amp Camp Project — Pass DIY / 2016

More...

A40 Part Substitutions — Nelson Pass / 2000

After 22 years, it appears that quite a few DIY enthusiasts are still eyeing the A40 Class A amplifier design, but are discovering that not a single transistor from this design is still available. The following information is for those scouting out substitute parts: The Lambda output devices are no longer available, and they weren’t that common to begin with. Lambda appears to still be in business, but not in the business of power transistors. Common everyday complementary power darlington transistors will substitute for these. They need to be rated at 75 watts or higher, 5 amps for higher, and… More...

Copyright © 2016 Pass Laboratories, Inc. All rights reserved

Telephone: 530.878.5350