The TAP knob controls the mix of main delay vs. Clockwise movement favours the second tap; counter clockwise favours the main delay. The result is a warm, smooth sound reminiscent of the vintage tape units used in the 50s and 60s. The DeLayla is able to capture one of the hardest sounds: that authentic rock n roll slapback echo that digital processors are unable to emulate.The unit also features a built in regulated (+-12V) power supply. With the exception of Brazil, all orders from South America Peru, Chile, Venezuela, etc. The item "Carl Martin Delayla Vintage Style Echo Tape Analog Delay Guitar Effect Pedal" is in sale since Tuesday, February 28, 2017. This item is in the category "Musical Instruments & Gear\Guitars & Basses\Parts & Accessories\Effects Pedals\Delay, Echo & Reverb". The seller is "srzmusic" and is located in Eureka, California. This item can be shipped worldwide.