In normal phase HPLC, the mobile phase is relatively non-polar and the. stationary phase is relatively polar. Other more general types of HPLC include partition, adsorption, ion-exchange, size-exclusion, and thin-layer chromatography.
This particular guitar loop pedal is the Boss RC-30. Simply put, a loop pedal is a device used to capture sound clips which are then played over and over again (looped) and often overdubbed. While loop machines have been around for quite a while, the idea of a guitar loop pedal is relatively recent. Instead of the traditional box controlled by the hands of a DJ, loop pedals allow guitarists to control the looping and overdub features via foot switches.
How to Use a Guitar Pedal. Guitar pedals, sometimes called effects pedals, effects units, or stomp boxes, are small electronic units that alter your guitar's sound in a specific way. Traditionally, guitar pedals are used to produce special effects such as wah-wah, delay, tremolo, chorus, flanger, distortion, and fuzz.