The Midium

Stacks FX's description of the Stacks FX Zeñor analog overdrive pedal (Signature Edition signed by creator Miguel Vasquez and artist Baked Papaya)



Cam: Recognizing the people behind a musical instrument's creation is as vital as recognizing the artist who plays it, and the audience who appreciates it. In that spirit, The Midium® asked Miguel Vasquez––founder of Stacks FX––and artist Baked Papaya (@bakedpapaya), who did the custom art on the Stacks FX Zeñor pedals in our collection at The Midium®, to please sign them for us and our Artists. It is our hope at The Midium® that you feel a deeper connection with your Stacks FX Zeñor analog overdrive Signature Edition, with the knowledge that the makers have added a personal touch to the pedal you order from us. We hope you enjoy this special pedal, as it was designed, created, and built by Miguel Vasquez (a local Southern California-based pedal inventor who is challenging established design and tonal principles with his music machines and effects units) and his partner Baked Papaya (@bakedpapaya), whose paintings and art can be enjoyed at various locations, galleries, and exhibits in SoCal and beyond.



Most overdrives are tailored for very specific sounds. They give you 3 parameters that mostly get the job done but I [Miguel Vasquez, owner of Stacks FX and creator of the Stacks FX Zeñor overdrive pedal] felt I needed more flexibility. I wanted something that could cover a wide range of sounds without sacrificing the overall tone. I experimented for months and months on my breadboard. I distilled/re-examined everything countless times and after reaching the brink of insanity, I came up with this circuit.

The Stacks FX Zeñor overdrive has six control knobs and two 3-position toggles. With these 8 parameters, you can get a WIDE range of sounds. It nails low and mid-gain sounds.

It can be a clean preamp that just lifts and sculps.

It can be a great dynamic "edge of breakup" drive with great touch sensitivity.

When dimmed, it can dish out saturated rhythms and leads. Stacks really well with other drives and it won't mangle your fuzz sound if placed after your fuzz pedals.

With the BLEND control, you can make it as transparent as you'd like! All the classic sounds and beyond.

Premium components were chosen for ultra-low noise operation and sound quality. This pedal quickly became my personal favorite. I'm now using three of these on my pedal board for boost, light overdrive, and main drive. Plus I can stack them together in different combinations for even more sounds! It's madness.


  • VOL is your final output level and there's plenty on tap for clean boosting into your amp. 

  • BLEND goes between your clean unaffected signal and overdrive signal paths. 

  • DRIVE controls the amount of saturation. Starts really clean and adds saturation and harmonics as you turn it up. The amount of available saturation is dependent on clipping toggle positions. 

  • CUT is a high-frequency filter that acts as a LPF. Gentle, very musical. 

  • MID controls the amount of cut or boost to the mid frequencies centered around 630hz with a gentle slope. Flat position means it's doing nothing. 

  • DRIVE BODY (BASS) controls how much the low end is being saturated. This pretty much works as a bass control but also really affects the feel and overall low-end grit. 

  • HARD CLIPPING toggle selects between MOSFET clipping (OCD, Fulldrive style) and GERMANIUM diode clipping (Klon style). Both are different sounds with different amounts of available gain. 

  • SOFT CLIPPING toggle selects between SYMMETRICAL clipping (TS-808 style) and ASYMMETRICAL clipping (Lightspeed, Timmy style). When both toggles are in the NONE position, you are getting pure 4558 opamp clipping. 

  • These 2 toggles give you 9 different possible clipping combinations. 

  • 9 to 18 Volt operation. 2.1mm Center negative jack. Draws less than 20mA

**All parts and components are top-notch, Wima and Nichicon fine gold foil capacitors. JRC and Burr-Brown op-amps. Heavy-duty 3pdt foot switch. Solid aluminum knobs. Powder-coated enclosure with control panel overlay.