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The original F5 amplifier was a commercial product made by First Watt in 2008, and like other FW projects, in a limited quantity. Also like other FW amplifiers it was relatively low power Class A, emphasizing simplicity and sonic quality.


  • Simpler design to the original F5, without compromising the qualities which made the original popular.
  • Input impedance: 47k Ohm
  • Damping factor: ~50

A range of 2U, 3U and 4U deluxe-style chassis with UMS are in the works to suit this amplifier, and expected to be available in late June. Don't let that stop you from building your amp now if you'd like to DIY your chassis or order one from Modushop. 

Please select from the two products listed below to make your purchase:


  • F5M Essentials

    Original price $ 40.00 - Original price $ 40.00
    Original price
    $ 40.00
    $ 40.00 - $ 40.00
    Current price $ 40.00
    Out of stock

    F5M Essentials kit, consisting of one PCB for each channel, a PCB for the power supply, and active devices.  Limit 1 per DIYer (combining a shipmen...

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  • F5M Completion Kit

    Original price $ 85.00 - Original price $ 85.00
    Original price
    $ 85.00
    $ 85.00 - $ 85.00
    Current price $ 85.00
    10+ in stock

    F5M completion kit, which contains a bunch of things to help you complete the amplifier. It does not include the essentials kit, nor a transformer,...

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