FET/RACK Revision F
Partial DIY Kit


Message About Price Increases

Customize your build

This kit is for the DIY enthusiast who has parts, experience, and the desire to tinker.

You’ll receive all of the hard-to-source parts for the build in the Hairball Audio partial kit. Obtaining the rest of the parts is up to you. You can utilize our pre-loaded mouser cart, located in the "Mouser BOMS" tab below, or go your own route.

NOTE: In the current supply-chain crisis, ordering all of the missing parts could end up costing more than simply purchasing the complete kit.  This Partial kit is intended for pro DIYers who have parts already in-house or are savvy at sourcing parts.

Recommended for advanced builders.
  • Revision F (v1.12) PCBs designed by MNATS 
  • Black anodized front panel with red stripe made in Seattle, USA
  • Custom 18 gauge steel zinc plated enclosure made in Seattle, USA
  • Custom Ed Anderson O-12 reproduction input transformer made in the USA
  • Custom Ed Anderson B11148 reproduction output transformer made in the USA
  • Custom Ed Anderson 11754 reproduction power transformer made in the USA
  • Custom BI Technologies T-Pad input attenuator, output, and attack pots.
  • Bourns release pot
  • Custom VU Meter
  • Interlocking push button switches with “All Buttons In” mode
  • JST connectors and pre-assembled wire harnesses
  • All mounting hardware
  • Matched FETs
  • Authentic control knobs


Not all of the parts needed to complete your build are included in this partial kit. This kit is designed for more advanced builders who are not afraid to source parts, or already have parts in their shop.

Mouser.com Cart Sharing
Mouser.com has a feature that allows us to create a custom shopping cart pre-loaded with most of the additional parts you need. To use this feature, simply click the Mouser cart link below. This will fill your cart with the parts you need for your revision. You can edit your cart and customize it all you like, you will not be altering our saved cart.

FET/RACK Revision F (Latest Version)
Mouser Cart Link | Bill of Materials PDF Download

Mouser.com does not stock the MPSW06 and MPSW56 output transistors. You need one of each. Check Newark or Farnell for them or email us and ask us to toss a set in your kit.

If you'd like to learn more about substitutions for out of stock parts, please have a read through our substitution guide.
Substitution Guide.

Digikey.com may also have stock it Mouser is backordered.

Disclaimer: Lists are not guaranteed to be accurate. We do our best to double and triple check the lists however we update them a lot and do make errors. Hairball Audio, LLC is not responsible for any BOM errors. If you do find an error, please let us know so we can update our BOM's for accuracy.

Build Support Services

We got your back! We offer flat rate repair on all of our DIY builds if you get stuck.

Get info on Build Services

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