Cooltron
The Cooltron series of pedals was created by Vox, a company that began back in 1957.
They produced only guitar amps at that point, but today, they now have many different lines of amps and pedals. The Cooltron effects pedals all feature 12AU7 preamp tubes that operate at a low voltage. The Cooltron pedals are some of the only pedals to make use of this type of tube since it is very difficult to use tubes in battery-powered pedals. However, the seven different Cooltron pedals all not only do this but they also add incredible sound and tone to your instruments.
The Cooltron pedals achieve this by using special circuits that use two special signal paths. The first creates the conditions for the tube to work. The second is the main power supply that constantly provides a low voltage power to the tube’s heater elements. This allows it to operate on a much lower power level. It doesn’t generate nearly as much heat as a full amp would, which is why it can be done in a pedal. Because of this lower power usage, each Cooltron pedal can run for 16 hours on just 4 AA batteries. (more...)


However, with just a flick of a switch, you can move over into full-range mode and boost all of your frequencies at once. This makes it very easy to make your overdriven amp move into heavy drive mode. The Cooltron features a gain control that allows you to add anything just a bit of mellow gain to full on, plus the tone control allows you to make fine adjustments to the EQ. The Cooltron also features true bypass so you will get completely unaltered tones when the pedal is not engaged.