The TUBE-TECH CL 2A is an all-tube optical compressor with two independent, linkable channels. CL 2A is a great compressor on all sources, and it is widely known as an excellent "problem solver" when delicate gain control is called for. Use it on keyboards, guitars, vocals or even on the mix buss – the result is always musical, smooth and transparent. Among engineers, the CL 2A is loved because of its ability to keep instruments at their right place in the mix, while still retaining their dynamics.