Zenductor III BAF Edition (No PSU)
This kit contains everything you need to build two Zenductor III monoblocks except the power supplies. A 12VDC supply capable of delivering 3A is required for each channel. The barrel connection is 5.5mm x 2.1mm with a center positive.
The photo is one channel; one monoblock.
This is the famous Zenductor III created by Nelson Pass for the 2025 Burning Amplifier Festival (BAF) Build Camp.
Two monoblock amplifiers can be assembled by most DIYers in an afternoon.
Details
The Zenductor III continues in the series of fabulous little amplifiers inspired by Mike Rothacher. It is an exercise in simplicity with lovely results. It is reminiscent of the original Zenductor, but simplified further.
"So here we are, Zenductor #3. I think you will find it surprising that so little can deliver so much. I am running my 86 dB / 3.8 ohm SR1's will them, and it sounds great and plays pretty loud." - Nelson Pass
Please read Nelson's article for additional details.
Link to Nelson Pass Zenductor III article
For an overview of the build process, please see the Zenductor III thread at diyAudio.com. Since BAF '25, the feet were changed to aid in stability and a few parts values were updated. Please be sure to read the thread for all updates. Nelson's article provides the history, the thread provides current information.. As always, a huge thank you to Jim (a.k.a. 6L6) for creating an exceptionally well-documented guide.
Important Information
This is an open chassis project. The heatsinks reach temperatures approaching 70C, 160F for a typical build. If you have children, pets, anyone, or anything that could be injured, scared, or damaged by these temperatures, please adjust the bias current to a level suitable for your environment and/or increase the heatsinking. They should be operated in an area with at least 8" of ventilation on all sides. Do not operate them in a fully closed rack.