Moreschi Wah-Fuzz (A Gary Hurst Design) Pedal Teardown
The first of the legendary line of Tonebender fuzz pedals was the unofficially-named Tonebender Mk1. Pre-dating the Fuzz Face and of course the more common Tonebender Mk2, the Mk1 was a tweak on the circuit topology used in the very first fuzz pedal, the Gibson-built Maestro FZ-1. While the FZ-1 was powered by 3V, the Mk1 was modified to use 9V battery power, and tends to have more output volume and sustain than an FZ-1. The Mk1 was designed and built by Vox Engineer Gary Hurst, and originally built in a wood enclosure. Gary Hurst later partnered with Macari’s Musical Exchange, and the Tonebenders started being branded with Macari’s Sola Sounds brand. Gary Hurst was also involved in the design of the Tonebender Mk2, which was often marketed as a “Gary Hurst Design”.
Gary Hurst went on to design and build a variety of pedals, many under his Electronic Sounds brand. Gary Hurst also built his pedals for other brands, including CBS/Arbiter. Gary also built pedals for the Italian company Moreschi, which was mostly known for its accordions.
The Moreschi Wah-Fuzz uses Gary Hurst’s design for the Electronic Sounds UFO Wah Fuzz Swell. While the Electronic Sounds pedals and the Gary-Hurst-designed CBS/Arbiter pedals came in a large plastic enclosure, the Moreschi pedals use metallic blue folded steel enclosures. The Moreschi Wah-Fuzz has a 2-transistor silicon Fuzz Face topology for its fuzz section which precedes the wah section. Both the Fuzz and Wah sections can be engaged or bypassed. Though the circuit topology is the same as the Fuzz Face, many of the component values are different which will result in different voicing. Note also that RV2, the volume pot, is wired differently, and there is a miller cap on Q1 for taming some of the high frequencies.
While better-known for his 3-transistor fuzz designs, Gary Hurst has claimed to be the original designer of the Tonebender Mk1.5[1], which uses a 2-transistor Fuzz Face topology. The origins of this topology in fuzz pedals is disputed, but Gary Hurst is one of the more likely possibilities.
The original footswitches have been replaced and a DC barrel jack has been added to this particular unit. Those modifications are not represented in the schematic.
Figure 1: Moreschi Wah-Fuzz schematic
Figure 1 is the schematic taken from a trace of an original unit. In this unit, R8 was bypassed with a simple wire lead. Doing so will provide more gain out of Q3, which a previous owner must have determined was beneficial to the Wah section.
Figure 2: Moreschi Wah-Fuzz board trace
Figure 2 shows both sides of the Moreschi Wah-Fuzz circuit board, as well as the component side of the board with component annotations and traces drawn. Note that although C7 is soldered in a strange location, it is present in other units as well. There are solder pads for it which are unused. It is possible the original needed to be replaced at some point.
Note also that ES-60 is written on the trace side of the board. “ES” is possibly an abbreviation of “Electronic Sounds”, Gary Hurst’s pedal brand.
| Transistor | Collector | Base | Emitter |
|---|---|---|---|
| Q1 | 1.73 V | 0.62 V | 0 V |
| Q2 | 6.22 V | 1.73 V | 1.09 V |
| Q3 | 4.36 V | 0.69 V | 0.1 V |
| Q4 | 9.35 V | 3.75 V | 3.3 V |
| Q3 (R8 bypassed) | 3.79 V | 0.59 V | 0 V |
| Q4 (R8 bypassed) | 9.41 V | 3.27 V | 2.81 V |
The table above shows the voltage measurements taken from each transistor leg. These can be useful for biasing the transistors to match original units. Q3 and Q4 voltages are included both with and without resistor R8 bypassed. The voltages on Q1 and Q2 did not change.
Citations:
[1] Rae, Kit. "The Tone Bender Timeline" www.bigmuffpage.com/The_Tonebender_Timeline_3.html. Accessed February 1 2023.