The R Weaver FX Silicon Face of Spades Fuzz is a handbuilt two-transistor fuzz pedal. R Weaver FX describes it as based on the legendary Square Face Fuzz built by Cesar Diaz, and says it can go from full-on wooly fuzz, down to a gritty overdrive tone, and all the way down to a nice glassy, chimey clean tone1. That range comes from the Fuzz Face style circuit layout, where rolling the guitar's volume back cleans the circuit up, a behavior shared with related designs like the Dunlop Fuzz Face Mini Silicon.
The controls
The Silicon Face of Spades keeps the classic two-knob Fuzz Face layout1:
| Control | What it does |
|---|---|
| FUZZ | Controls the amount of fuzz or distortion of the circuit1 |
| VOLUME | Sets overall output level1 |
The bypass footswitch uses true bypass to take the fuzz effect out of the signal path1. In the broader Fuzz Face circuit family, the fuzz control is a low-value pot and the volume control a higher-value audio pot, a pairing documented in independent circuit analyses of the silicon Fuzz Face design2.
Transistors and circuit
The pedal uses two NTE123AP silicon transistors. R Weaver FX says these offer great fuzz and sustain and nice stable performance even in hotter temperatures1. Silicon transistors are the usual choice for players who want Fuzz Face behavior without the temperature sensitivity of germanium; Dunlop's silicon Fuzz Face Mini likewise uses silicon transistors like the later '70s Fuzz Face, as Vintage Guitar magazine's review noted3. The pedal is built on a high quality multi layer PCB, which the maker says is for durability and minimal noise floor1.
Silicon Fuzz Face circuits can be prone to oscillation, which is why some layouts of the circuit offer an optional filter cap version, as the Guitar FX Layouts project noted in its NPN silicon Fuzz Face layout4. The maker's product page for the Silicon Face of Spades does not go into this detail, so treat the pedal's behavior as the maker and your own playing describe it.
Power and warranty
The pedal runs on a standard 9V 2.1mm center negative DC power jack, and the maker is explicit: use a 9V isolated Power Supply only1. A 9V battery also works, with a Carbon-Zinc type recommended1.
Because the maker specifies an isolated 9V supply only, a daisy-chained or non-isolated supply is off the table for this pedal.
R Weaver FX says the pedal is handbuilt with premium components for durability, and it is backed by a 1-year, non-transferrable warranty against operational defects1.
Availability
As of 26 October 2026, the maker's product page lists the Silicon Face of Spades as sold out, at a listed price of £152.00 GBP1. R Weaver FX also builds other takes on the design family, including the Face Of Spades Axis Edition.
Videos
Vivien Verdier
Sergei Pugachev
Questions
What circuit is the R Weaver Silicon Face of Spades based on?
R Weaver FX describes the Silicon Face of Spades as based on the Square Face Fuzz built by Cesar Diaz. The Square Face itself belongs to the Fuzz Face family of two-transistor fuzz circuits, the same design family that the Dunlop Fuzz Face Mini Silicon carries on with silicon transistors. The pedal uses two NTE123AP silicon transistors, which the maker says offer great fuzz and sustain and stable performance even in hotter temperatures.
Is the Silicon Face of Spades true bypass?
Yes. The maker's product page lists True Bypass switching, and the bypass footswitch uses true bypass to take the fuzz effect out of the signal path. That means the pedal's circuit is removed entirely when off, leaving your guitar's signal to pass straight through to the output.
Can I use a non-isolated power supply with the Silicon Face of Spades?
No. The maker specifies a standard 9V 2.1mm center negative DC power jack and says to use a 9V isolated power supply only. A daisy chain or non-isolated supply is ruled out by that instruction. A 9V battery also works, with a Carbon-Zinc type recommended.
What transistors does the Silicon Face of Spades use?
The pedal uses two NTE123AP silicon transistors. R Weaver FX says these offer great fuzz and sustain and nice stable performance even in hotter temperatures, a common reason builders choose silicon over germanium in Fuzz Face style circuits.
Does the Silicon Face of Spades have a warranty?
Yes. The pedal is backed by a 1-year, non-transferrable warranty against operational defects, according to the maker's product page. R Weaver FX also notes the pedal is handbuilt with premium components for durability.
Sources (4)
- Silicon Face of Spades Fuzz, R Weaver FX Handbuilt Pedals
- bbp_FuzzFace_Rev1_2, beavisaudio.com, 2019
- Dunlop Fuzz Face Mini Distortion Pedals, Vintage Guitar magazine, 2015-01-07
- Guitar FX Layouts: NPN Silicon Fuzz Face, Guitar FX Layouts (tagboardeffects.blogspot.com), 2012-06-02
