Coopersonic Audio Engineering produce a range of hand-wired effects in Nottingham, England. Not all of them feature vacuum tubes, but two of their most talked-about pedals — the Valveslapper and Tubecleaner — make no secret of their valve-centric design. The Tubecleaner is described as a valve booster and buffer and, with just one knob to control volume, it's the simpler and more compact of the two pedals. While the larger Valveslapper uses a pair of full-sized, dual-triode valves, the Tubecleaner employs a single sub-miniature 6112 valve, which is a military-spec dual-triode.
The Valveslapper, billed as a tube overdrive, has controls for volume, bass, treble and gain — amusingly (or not, depending on your point of view) labelled thrust, balls, tits and ass, respectively. Inside are two 6N2P-EV valves, which can be swapped for 12AX7s or, indeed, 12AU7s or 12AT7s if you wish to experiment with the amount of gain on tap.
Neither pedal features any kind of vent or opening to let out heat generated by the valves. Preamp-type valves like these do not produce anything like the heat of the larger valves you'd find in a guitar amp's power section, but the Valveslapper, in particular, does get very warm in use. This will ultimately shorten the life of the valves and possibly other components too, although their life span should nevertheless be long. In short, it's not ideal, but it's not catastrophic either!
Each pedal requires a non-standard power supply, thoughtfully included by Coopersonic. There's a 9V DC centre-positive supply for the Tubecleaner, and 12V DC centre-positive for the Valveslapper. Running either off a communal supply would not be advisable in any case, due to their high current demands. Both pedals multiply the voltage internally, so the valves can work on the proper high voltage, meaning that they both draw a lot of juice.
While many valve overdrive pedals are designed to act as a low- to medium-gain preamp, the Valveslapper is most definitely a distortion device. Sharing the same taste for edgy, aggressive distortion as the rest of the Coopersonic range, this is most definitely not a smooth blues machine! Classic rock, punk and even metal, however, are on the menu, but the Valveslapper is not just about top-end bite and break-up. The sounds on offer are full-bodied and solid in the low end too. For anyone with a good-quality single-channel valve amp who wants to instantly add a distortion channel, this could be the ideal solution. If a straightforward distortion stomp-box is what you're after, there are plenty of less bulky, less costly alternatives to choose from, but although this is undoubtedly a deluxe option, for a hand-built device the price is very reasonable.
While the Valveslapper will certainly give your valve amp a good slap about the chops, the Tubecleaner is equally true to its name, providing up to 22dB of completely clean and full-sounding boost. When the processing is bypassed, the indicator LED is green, reminding us that this pedal is acting as a signal buffer, sending out a low-impedance signal that will retain treble detail over long cable runs. Switched on, the LED is red and the volume knob comes into play. The gain on offer might be clean, but there's more than enough of it to push a good valve amp into overdrive. It's also highly effective when placed in front of other overdrive and distortion pedals — applying a moderate boost here can create some wonderful additional sustain and break-up. As with the Valveslapper, the need to accommodate an additional adaptor on your pedalboard is one of the few negatives you can pin on the Tubecleaner, a pedal that delivers great results and is actually cheaper than some solid-state, mass-produced boost pedals. David Greeves
Valveslapper £149; Tubecleaner £109. Prices include VAT.Valveslapper £149; Tubecleaner £109.