nux optima air dual-switch acoustic guitar simulator with a preamp,ir loader, capturing mode nux nux optima air is a dual-switch acoustic guitar simulator with a preamp for acoustic and electric guitar players. it simulates the acoustic guitar profiles with the best-optimized sound depending on your guitar and pickup type. ir loader combined with a preamp which is equipped with 3-band eq and gain controls. and there is an additional one-knob-control reverb effect. if you want to connect any effect pedal you can use the send/return effect loop and add the optima air into the signal chain. nux optima air has a unique profile capture function, you can create your own acoustic guitar profile (ir file) by capturing your favorite acoustic guitar's sound. there is an xlr di output for direct line/mixer connection, headphones output for silent play and auxiliary input to connect a music player to play along.