The Seamoon Funk Machine is an all-analog envelope filter with a built-in sub harmonic generator, made in the USA by Seamoon1. An envelope filter opens and closes a filter in response to how hard you play, producing the elastic, vowel-like "auto-wah" sound heard on funk records. Seamoon describes the Funk Machine as providing "a chromatic wonderland of envelope filter fun-with a few added surprises"1.
The design dates to the 1970s, when audio filters first arrived on working guitarists' pedalboards and Seamoon released the original Funk Machine2. Premier Guitar's history of stompbox classics notes that "Seamoon was best known for the Funk Machine (designed by well-known DIY author Craig Anderton)"3. Seamoon has since brought the pedal back, announcing its return in August 2026.00 USD14.
The controls
The current Funk Machine carries four knobs1:
| Control | What it does |
|---|---|
| Frequency | Sets the center frequency of the filter, the core of the effect's vocal character |
| Blend | Mixes the filtered signal with the dry signal |
| Depth | Sets how far the envelope sweeps the filter |
| Volume | Sets the output level |
The sub harmonic generator is the added surprise in the circuit: alongside the swept filter, it produces a sub harmonic of the played note, which is one reason the pedal has drawn interest from bass players1.
Guitar, bass and horns
Seamoon says the Funk Machine is "Equally at home with guitar, bass and horns"1. The company also lists the pedal as a bass envelope filter5, and it sits naturally among bass pedals for players who want a dynamic filter rather than a fixed wah. Because an envelope filter tracks picking strength, it responds well to the low, percussive attack of a bass.
History and the ADA connection
The Funk Machine belongs to the first wave of envelope filter pedals. GuitarPlayer's look at six pioneering effects builders of the 1970s, speaking with Art Thompson, Chris Gill and Rod Brakes, observes that "Seamoon's Funk Machine and Studio Phase look suspiciously like precursors of ADA's Flanger and Final Phase"62. That makes the Funk Machine an early Seamoon design whose visual and circuit ideas resurfaced later in ADA's rack-era effects.
Seamoon also makes the related Funk Filter, a separate envelope filter pedal in the current lineup2. The Funk Machine returned most recently with Seamoon's August 2026 announcement1.
Videos
SEAMOON FX
SEAMOON FX
BassTheWorld.com
Questions
Who designed the Seamoon Funk Machine?
The Funk Machine was designed by Craig Anderton, a well-known DIY electronics author. Premier Guitar's history of stompbox classics notes that Seamoon was best known for the Funk Machine, and credits Anderton as its designer. Seamoon released the pedal in the 1970s, when audio filters first arrived on working guitarists' pedalboards.
Is the Seamoon Funk Machine analog?
Yes. Seamoon describes the Funk Machine as an all-analog envelope filter with a sub harmonic generator. The circuit is analog throughout, and the sub harmonic section adds a note an octave below the played note alongside the filtered signal.
Can I use the Seamoon Funk Machine with bass?
Yes. Seamoon's product page says the Funk Machine is equally at home with guitar, bass and horns. The company also lists it as a bass envelope filter, and bassist Neil Jason has presented it among Seamoon's bass-centric pedals. Envelope filters respond to playing dynamics, which suits bass well.
Is the Seamoon Funk Machine related to the ADA Flanger?
There is a documented family resemblance. GuitarPlayer's history of pioneering 1970s effects builders, quoting Art Thompson, Chris Gill and Rod Brakes, describes Seamoon's Funk Machine and Studio Phase as looking suspiciously like precursors of ADA's Flanger and Final Phase.
Where is the Seamoon Funk Machine made?
Seamoon builds the Funk Machine in the USA. The company states this plainly on its product page, and the current version is sold directly through Seamoon's own site.
Sources (6)
- Funk Machine, Seamoon FX, 2026-10-07
- Knight School Filter DIY Kit, Catalinbread Effects
- Stompbox Classics: A/DA Flanger, Premier Guitar, 2008-05-12
- MORE! - Seamoon FX Pedals, Seamoon FX
- Octatron, Seamoon FX, 2026-10-07
- Six Pioneering Effects Builders of the 1970s, GuitarPlayer, 2022-05-26
