Hello all. To be honest, I'm not sure if this is a .22 or a .22 +, never been able to figure that part out. It is a late '80's, according to Boogie, and 87. It is a two channel amp, but it has one set of controls. The EQ can be set to be always on, never, or only in the lead channel. There is a Boogie mod to give separate volume controls for each channel. Very cool amp but when stacked next to my Recto-verb, well....... Dan