Boss CS-2 Compression sustainer compressor (black label, made in Japan, s/n 225500)

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Introduced in 1981 as the successor to the CS-1, the Boss CS-2 Compression Sustainer is a vintage analog compressor with an immediate response and smooth sustain. It reduces the difference between hard-picked and softer notes, helping clean chords, arpeggios and rhythm parts sound more even. At stronger settings, the compression becomes more audible and helps lead notes ring longer. The CS-2 uses a VCA circuit and has three controls. Attack shapes how the compressor responds to the start of each note, so you can retain more of the pick’s impact or soften it. Sustain sets the amount of compression, while Level adjusts the output volume. This gives you a choice between subtle control of your playing dynamics and a more pronounced compressed sound. Notable CS-2 users include David Gilmour (Pink Floyd), Matthew Bellamy (Muse) and Mark Knopfler (Dire Straits). This example was made in Japan and has a black label and serial number 225500.