VFE Dragon Hound

The VFE Dragon Hound is a dual overdrive and distortion pedal that combines the core circuits from two other VFE designs, the Alpha Dog distortion and the Pale Horse overdrive, into one box¹. Instead of stacking the two gain stages in series, it runs them in parallel and blends between them, so each circuit keeps its own character while the mix control sets how much of each you hear¹².

The idea came out of designer experimentation with multiband distortion. As the project documentation puts it¹:

The result, in the maker's description, is a pedal "able to add more harmonic saturation without losing the clarity of each note, and do it naturally"¹. The first prototype was code named "Crown Jewel"¹. The original built pedal is now discontinued².

What it does: overdrive and distortion in parallel

Most two-gain-stage pedals run one into the other, so the second stage clips an already-clipped signal. The Dragon Hound splits the signal instead, sending it through the Alpha Dog distortion circuit and the Pale Horse overdrive circuit at the same time, then blending the two outputs¹². Each circuit has its own dedicated drive control, and the blend control can dial in saturated distortion tones that retain the clarity of an overdrive².

The maker's own preference is telling: the designer writes, "I prefer the Dragon Hound over both the Alpha Dog and Pale Horse, especially for chords"¹.

The controls

The pedal has six knobs, plus one internal trimmer¹.

Because FAT is dual-gang, it shifts the low end of both parallel circuits together rather than thickening one side and not the other¹. One documented modification narrows the Filter control's range: lowering C17 from 47n to 22n reduces the full counter-clockwise treble cut and gives more control over the clockwise setting¹.

Power: bipolar supply, about 33mA

The Dragon Hound does not run on a standard single-supply pedal power scheme. The project documentation states plainly: "This circuit does use the bi-polar power option (+/-9v)"¹. Current draw is about 33mA, measured on a 9.42V One Spot supply¹. You can use a 12V or 15V Zener for the protection diode on the switching board¹.

For anyone debugging a build, the documentation includes reference voltages taken with all knobs set to noon: IC1 (LM308N) pin 2 reads 4.27, IC2 (OPA2134a) pin 1 reads -250mV, and on the 2N5458 JFET the drain reads 8.62, the source 0.75 and the gate 0¹.

Building one: the DIY board and layouts

Although the built pedal is discontinued, the Dragon Hound lives on as a DIY project. VFE released its design files, including the Dragon Hound's, in a public archive¹, and the project documentation permits purchased circuit boards to be used for both DIY and small commercial operations. The PCBs themselves may not be offered for resale or as part of a commercial kit, though peer-to-peer re-sale is fine¹.

Two routes exist for a builder:

• The official PCB, documented in the VFE project file, with build notes, voltage references and a parts list¹.
• A vero (stripboard) and tagboard layout, available for DIY build and verified working by builder glasspak73².

On difficulty, the documentation is encouraging: "As vfe builds go, this one is actually pretty easy even with two circuits in one," though it notes that a couple of areas on the 16mm pots are a bit tricky to solder¹. Technical assistance for builds is available through the madbeanpedals forum rather than by email¹.

Parts are mostly standard, with two exceptions. The LM308N op-amp must be sourced on your own, through eBay, forum members or other online shops¹. The 2N5484 JFET is also hard to get, and a J113 can be substituted since it has the same pinout¹. Note that the two JFETs in the circuit are different: a 2N5484 and a 2N5458, and they are not interchangeable positions¹.

glasspak73's verified build report is a useful data point for anyone considering the project. He moved the COMP trimmer outside as a B100k pot, and reported²:

He went on to describe it as his main overdrive/distortion².

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