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Aleph J MOSFET and JFET kit

Part of the Aleph J project
Choose ConfigurationCurrently Selected: MOSFETs & JFETs
$ 80.00 USD
Circuit Boards
$ 25.00 USD
$ 60.00 USD
$ 60.00

Included in this kit are the following semiconductors needed to complete an Aleph J amplifier. This kit provides for 2 channels (one stereo amplifier).

MOSFETs and JFETs were graded and matched specifically for use in the Aleph J by expert hands.

Kit Contents:

  • 8 x IRFP140/240 N Channel MOSFETs (all 8 are matched to within 0.1V)
  • 4 x Linear Systems LSJ74 (4-5mA, matched to 1mA)
  • 4 x ZTX450
  • 2 x ZTX550


  • Current batch contains IRFP048 instead of 140/240

    Aleph J Project

    • Power Amplifier
    • Designed by Nelson Pass
    • Intermediate Difficulty
    • Basic Build Guide
    • Only PCBs Available

    Visit the Aleph J project page for more information about this project.

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    Aleph J MOSFET and JFET kit

    $ 60.00 USD

    Note - Photos include parts available at the time of publishing. Individual components are subject to change based on availability.

    Customer Reviews

    Based on 15 reviews
    david p.

    I made mono blocks with the superb pcb you are selling and the fets.
    i am astonished by the results. they have only few hours and they start to open up!
    Thanks Mister Pass and DIY audio store, what you do is revolutionnary.

    Marco L.

    Great Kit it all worked first try. It's a great price and you know you get genuine parts. So highly recommended!!!

    Jun L.
    Aleph J

    It came nicely packed and I actually bought this FET Kits separately and bought the other parts to complete the whole Aleph J Amp. The sound signature of this design, thanks to the very generous Mr. Pass is so unique with holographic and engaging sound stage, well controlled lows and very sweet mids and highs.

    This is my reference DIY amp now after building the ACA and the F4. Its is just a cut above all the ones I built. So worth the time and money and I am delighted I decided to build it.

    Alpha J

    The kit worked flawlessly. Thanks very much!

    Kelly T.
    Outstanding Amp

    This was my first amp build and with the high quality boards and components, it was very enjoyable. I purchased another Aleph J kit and the M2X boards and power supply boards. I believe the boards are bulletproof and extremely well laid out which allowed a greater chance of success. The DIY Audio forum is extremely helpful, shout out to 6L6, and other for the build guides, not exactly paint by numbers but very well done.

    John S.
    No reason to expect anything but excellent

    My eyes are bigger than my stomach and I buy too much. I'll get to it, certainly, but haven't yet. Nonetheless, I'm sure I'll be happy with everything. Thus far all that I've purchased from Diyaudio has been well supported and as described. The electronics world can, it seems, be a tough crowd. I sometimes see stones cast at and Nelson Pass. The same two are responsible for me daring to try and succeeding. I'm very thankful despite not having any measurements of what I've built to date.