The Avalon AD2044 Dual Mono-Stereo, Pure Class A Opto-Compressor. For vocals, bass, acoustic piano, and across the mix bus, it is one of the most musical and transparent compressors available today. The Avalon AD2044 features 100% discrete, pure class A signal amplifier configured with high speed current monitored optical control elements. These "invisible" opto elements enable the AD2044 to deliver totally transparent, low noise gain reduction within the minimalist signal path design. No VCAs are incorporated. Variable attack and release controls plus side chain access, provide unlimited creative control from soft compression to hard limiting. The AD2044 can be found in the world's leading recording studio's, mastering facilities and artist/producers outboard racks. These professionals rely on the AD2044 daily to help them complete their "sonic signature" and turn recordings into musical masterpieces