EM1 Headphone Amplifier is a rechargeable and portable personal in-ear monitor amplifier specially designed for stage musicians. The excellent technical, tonal characteristics, high audio reproduction and non-audio rendering have been translated into a more compact format for EM1, so you can clearly hear the sound of playing on stage anytime, anywhere. Whether you are a drummer, keyboardist, vocal or other musicians, EM1 stage amplifier is an excellent stage partner. Meanwhile, EM1 is also used for practicing instruments and studio recordings as an audio monitor with high power and volume.