Many of the folks who work here are builders too, and we often have the occasion to put together interesting builds that we show off on our social media and elsewhere. When possible, we document the design and bill of materials so that these pedals can easily be built by any DIYers without going through the trouble of hunting down all the required parts.
This dual pedal is a combination of the classic Dallas-Arbiter Fuzz Face and the Dallas Rangemaster (treble boost). Fuzz + treble boost is a classic combo seen in pedals such as the AnalogMan Sun Lion and the Hornby Skewes Shatterbox. This version has an added bias control knob for the Fuzz Face side, and an input cap selector switch for the Rangemaster side. It is built on our black 20x10 vintage (0.15”) spacing stripboard.
The original Rangemaster had a single control (besides on/off), and that was the volume pot. The input cap selector is an easy way to expand the Rangemaster’s versatility by adding a control that changes the cutoff frequency of the input high pass filter. If you’d like to read about how it works, see our tech article Rangemaster Modification / Variant: Input Capacitor Switch.
Figure 1 is a stripboard layout for the Fuzz Face / Rangemaster combo pedal. Note that the input capacitor switch can be removed by simply removing the connections to it and changing the yellow 1nF capacitor to ~5nF. The bias knob can be removed by removing the connections to it (and the 2.2kΩ resistor) and wiring an 8.2kΩ resistor (or a 10k+ trimpot for trimmer bias control) from D11 to F11 or from D1 to H1.
Figure 1: Stripboard layout of an NPN Fuzz Face / Rangemaster combo build with input capacitor switch and bias knob.
Figure 2: Fuzz Face / Rangemaster NPN Schematic
The recommended wiring for the jacks and switches wires each section of the effect as if they were separate - the Fuzz Face section has its own footswitch and LED for engaging the effect as well as its own input and output jack, as does the Rangemaster section. However, the output jack of the Fuzz Face section and the input jack of the Rangemaster section both use a switched jack, with their switched contacts wired to each other. The result is that with nothing plugged into the Fuzz Face output jack or the Rangemaster input jack, the effects will be put in series with the Rangemaster after the Fuzz Face. This is the "default" way to use the pedal with a single input and output signal.
The Fuzz Face output and Rangemaster input jacks (also marked "SEND" and "RETURN" in Figure 3) can be used to insert external effects between the two, to switch the order (Rangemaster before Fuzz Face), or to use the two effects separately.
The input jack of the Fuzz Face section will disconnect battery when the plug is removed.
Figure 3: NPN Recommended Wiring
|1 kΩ Linear||R-VAM1KL-SS||Fuzz control |
|500 kΩ Audio/Log||R-VAM500KA-SS||Fuzz volume |
|10 kΩ Audio/Log||R-VAM10KA-SS||Boost volume |
|10 kΩ Linear||R-VAR-B10K||Fuzz bias |
|NPN germanium||P-Q2SD77||Fuzz Face Q1The NPN germanium transistor of your choice can be used here. P-Q2SD77 is a good option |
|NPN germanium||P-Q2SD77||Fuzz Face Q2The NPN germanium transistor of your choice can be used here. P-Q2SD77 is a good option |
|NPN germanium||P-Q2SD77||Rangemaster Q1The NPN germanium transistor of your choice can be used here. P-Q2SD77 is a good option |
|10 nF||C-MD01-630||Fuzz Face output cap |
|10 nF||C-MD01-630||Rangemaster output cap |
|1 nF||C-MD001-630||Rangemaster input cap |
|2 nF||C-R82-2N2||Rangemaster input cap (parallel) |
|3.9 nF||C-PEID0039-100||Rangemaster input cap (parallel) |
|10 nF||C-PEID01-100||Rangemaster input cap (parallel) |
|20 nF||C-PEID02-100||Rangemaster input cap (parallel) |
|47 nF||C-PEID047-100||Rangemaster input cap (parallel) |
|220 nF||C-PEID22-100||Rangemaster input cap (parallel) |
|2 μF||C-SA2-50||Fuzz Face input cap |
|25 μF||C-ET25-50-MOD||Fuzz Face emitter cap |
|50 μF||C-ET50-50-MOD||Rangemaster emitter cap |
|100 μF||C-ET100-100-MOD||Voltage stabilizing cap |
|470R||R-I470||Fuzz Face volume divider resistor |
|2.2 kΩ||R-I2D2K||Fuzz Face minimum bias resistorOptionally, replace with 100k trimmer to modify biad knob range |
|4.7 kΩ||R-I4D7K||Rangemaster emitter resistorOptionally, replace with 10k trimmer to vary bias |
|33 kΩ||R-I33K||Fuzz Face Q1 collector resistor |
|68 kΩ||R-I68K||Rangemaster base bias resistor 1Optionally, replace with 100k trimmer to vary bias |
|100 kΩ||R-I100K||Fuzz Face feedback resistor |
|470 kΩ||R-I470K||Rangemaster base bias resistor 2 |
|1 MΩ||R-J1M||Fuzz Face input cap shunt resistor(Optional, not in original) |
|1 MΩ||R-J1M||Rangemaster input cap shunt resistor(Optional, not in original) |
|1 MΩ||R-J1M||Rangemaster output cap shunt resistor(Optional, not in original) |
|Stripboard||P-PC-STD15-1-BLK||Black vintage-spacing 20x10 stripboard |
|2P6T rotary switch||P-H392||Rangemaster input cap selector |
|SPST rocker switch||P-H518||Battery enable/disable |
|Silver footswitch||P-H501-L||3PDT footswitch control for Rangemaster |
|Black footswitch||P-H501-L-BLK||3PDT footswitch control for Fuzz Face |
|Silver dress nut||P-H52-NUT-DRESS||Dress nut for Rangemaster footswitch |
|Black dress nut||P-H52-NUT-DRESSBK||Dress nut for Fuzz Face footswitch |
|Large black knob||P-K650||Fuzz Face volume knob |
|Large black knob||P-K650||Fuzz Face level knob |
|Large silver knob||P-K650-SIL||Rangemaster level knob |
|Small black knob||P-K670||Fuzz Face bias knob |
|Small silver knob||P-K670-SIL||Rangemaster input cap knob |
|Switched Lumberg DC jack||P-JBLB-IN-S||Power jack |
|1/4" stereo enclosed Switchcraft jack||W-SC-112BX||Fuzz Face input jack |
|1/4" mono enclosed Switchcraft jack||W-SC-112AX||Fuzz Face output jack |
|1/4" mono enclosed Switchcraft jack||W-SC-112AX||Rangemaster input jack |
|1/4" mono enclosed Switchcraft jack||W-SC-111X||Rangemaster output jack |
|Wire||S-W3024TC-BL-50||Offboard wire, topcoat, 24AWG |
|Red/black prewired LED||P-LPW-FLATBK-R||Fuzz Face indicator |
|Red/silver prewired LED||P-LPW-FLAT-R||Rangemaster indicator |
|Battery clip||K-P155||Power pedal with 9V battery |
|Gorva S90 black||P-H1590BB-GORVA-B||Enclosure |
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