The Carl Martin Andy Timmons Signature Compressor Limiter is one of the most useful and musical guitar processors on the market. It has 2x pre-sets one for more subtle parts and one for hard compression. In order to take up less space the Threshold and response settings are fixed for both pre-sets. There is an extra ¼ jack for switching the pre-sets (latching) The pedal can be powered via a 9V DC 200mA power supply but runs at +- 12 internally thanks to the newly developed DC/AC converter circuitry.