Benson Amps Stonk Box Fuzz Pedal

The Stonk Box takes the raw, primitive character of a classic MK1-style germanium fuzz and makes it considerably more controllable and consistent. Benson started with the basic architecture of the early Tone Bender MK1, with some of the midrange character associated with the Supa MK1, then expanded the circuit with additional control over gain, filtering, and overall tonal balance.

At the heart of the Stonk Box are germanium transistors paired with Benson’s Automatic Thermal Bias technology. Germanium devices are notoriously sensitive to temperature, so the pedal uses an analog circuit that gently warms the transistors to a predetermined operating point. This allows the bias and transistor gain to remain much more consistent as ambient temperature changes.

The indicator LED shows what the thermal-bias circuit is doing. Amber indicates that the transistors are being warmed, while green indicates that the target operating point has been reached and the heater has switched off. The LED may alternate between the two colors during normal operation as the circuit continually maintains the proper temperature and bias. After first applying power, allow roughly two to three minutes for the pedal to settle into its intended sound.

TRIM controls the gain immediately before the two amplifying germanium transistors. Fully clockwise corresponds most closely to the gain structure of the original circuit. FILTER changes both the gain and bias of the first gain stage; reducing it lowers gain and bass response while introducing an unusual dynamic-expander-like response. FILTER and TRIM are highly interactive, allowing the Stonk Box to move through a broad range of fuzz and distortion textures.

TONE is a low-pass filter placed at the end of the circuit and is designed to balance the naturally bright attack of the original-style fuzz with its full-bodied low and mid frequencies. VOLUME controls the final output level, with substantially more output available than the vintage circuit for pushing the front end of an amplifier.

Unlike some traditional vintage fuzz designs, the Stonk Box was also developed to be more tolerant of buffers and different pedal-order placements. It remains an intentionally primitive, aggressive fuzz circuit, however, and certain high-gain or high-output settings can produce significant hiss and noise as part of the effect.

Features:

• Heavily modified MK1-style germanium fuzz
• Supa MK1-influenced midrange character
• Germanium 2N404 or 2N527 transistors
• Benson Automatic Thermal Bias technology
• Analog transistor-heating and bias-regulation circuit
• More consistent response across changing temperatures
• Amber/green thermal-bias status LED
• Expanded four-control layout
• Interactive Trim and Filter controls
• Tone control for balancing bright attack and fuller body
• Significantly increased output level compared with the vintage circuit
• More buffer- and pedal-order-friendly than traditional MK1-style fuzz designs
• Top-mounted input, output, and power connections
• No battery operation

Controls:

• Trim: Controls gain ahead of the two amplifying germanium transistors
• Filter: Adjusts first-stage gain, bias, bass response, and dynamic behavior
• Tone: Low-pass filter for overall tonal balance
• Volume: Overall output level

Specifications:

• Effect Type: Germanium Fuzz
• Circuit Inspiration: Tone Bender MK1 / Supa MK1
• Transistors: 2N404 or 2N527 Germanium
• Bias System: Automatic Thermal Bias
• Controls: Tone, Volume, Filter, Trim
• Input: 1/4" Mono
• Output: 1/4" Mono
• Power Requirements: 9V DC only, center-negative
• Current Draw: Less than 100mA with heater engaged
• Battery Operation: No
• Power Supply: Not included
• Manufacturer Warranty: 2 Years
• Country of Manufacture: USA

Power / Setup Note:

Use only a 9V DC center-negative power supply. The Stonk Box requires a short warm-up period after power is connected before the germanium transistors reach their regulated operating point. The internal bias trimmer is factory-set and should not be adjusted.