It depends! If you have an older pedal like a mini tube pedal or one of the earlier X-series pedals then it is for adjusting the high voltage supplied to the tubes. Before the pedal was shipped, it was set at a specific value. If you really think you want to mess with this, please reach out to me via the Contact link above and I can give you more details. There is also an internal trimpot on the newer versions of Space Heater, Underground Accelerator, Dr. Wattson, and JC Emerald. This trimpot is usually labeled as "ATTEN" and it is an output attenuator that I add to pedals with an unusually hot output. It is effectively a second "master control" that will limit the overall master volume of the pedal. This is typically set right in the middle at shipping and can be adjusted to any position without damaging the pedal. Additionally Smoke Signal (May 2022 onward) has internal trimpots to adjust the brightness of the LEDs. These should be labeled as "RED" and "BLU" and control the respective red and blue channel LEDs on the pedal. Fluffy Kitten has 4 internal trimpots to adjust the voltage delivered to the JFETs in the pedal, these are biased specifically before the pedal is shipped and while adjusting them will not damage the pedal in any way, there are certain bias points where the pedal will not produce sound. Newer Fluffy Kitten units (July 2022 onward) have an additional trimpot towards the bottom of the circuit board that controls the brightness of the indicator LED.

The X series pedals became so popular, I decided to discontinue the submini tube pedals. 12AX7/12AT7/12AU7 tubes draw less power, are easier to procure, are easier to self-replace, and overall have less problems (like becoming microphonic).

It's a bit difficult for me to keep every color in-stock myself, so I now only stock black and silver knobs. If you're looking for something different, the exact knobs I use are these: Anodized Aluminum Knob - "The Magpie" - 1/4" Smooth Shaft (12.5mm OD)

Here's a few different power supplies that people have been using without issue:

• Cioks DC7 @ 9v setting
• Strymon Zuma with Voodoo Lab PPAP current doubler cable
• Truetone 1 Spot

No. All Sushi Box tube pedals have internal voltage regulators, which means whatever voltage you send it (9-12v) it is always running at the same internal tube voltage of ~235v. If you're looking to change the breakup, you could look at replacing the tube itself. Stop by Talkbass or TheGearPage forums and ask away! Or you can also find me on Facebook The exceptions are of course Fluffy Kitten and Echosaurus, neither of which have a high voltage regulator, so the voltage you give it is the voltage it's getting.

Up until now all builds have been using surface-mount (SMD or SMT) components for cost and ease of assembly. Currently these are mostly placed via pick-and-place machine in the same factory that manufactures the circuit boards themselves. There are a handful of specialty components that the factory doesn’t stock that are added by hand at Sushi Box, but the rest are done by machine. Hand-wired uses more traditional through-hole components that you’re likely to see in tube amplifiers, like carbon-composition resistors and film capacitors. There’s plenty of debate on the “sound” of different component materials and it’s extremely subjective so I won’t get into that. One very audible difference, however, is the voltage at which the tubes are run. In typical SMD builds I use 250V capacitors for cost and size reasons, so I run the circuits around 240V. The capacitors I use in the handwired builds range from 400V to 630V, which allows me to run the circuits around 350V. The difference in voltage gives the handwired circuits a noticeably warmer, fuller sound.

If the pedal you purchased is defective, I will take it back and either repair or replace it, and cover the cost of shipping it back to you. If a pedal comes back for repair and it is determined that either nothing is wrong with it or damage was caused by user error, the customer will be responsible for return shipping. If you are not satisfied with your purchase, you can request a return for refund. All refund requests must be initiated within 10 calendar days of receiving the pedal. All returned pedals will be subject to a 10% restocking fee, and pedals returned not in their original condition (i.e. damaged, missing pieces, etc) may be subject to additional fees. The customer is also responsible for any shipping costs involved in the return.