Previously Featured Builds

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Michele

Michele

Finally I am successful to finish to my Pearl phono stage. After any of vicissitudes for the tuning of the… More...
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Seungyun Lee

Seungyun Lee

In this project, we designed and developed the some PCB for input selection by using relay device. This board supports… More...

Amp Camp Project — Pass DIY / 2016

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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...

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