Raul,
I have some Yamaha amplifiers (M-80 and M-40) that have "Class A" switches on them.
Normally, the amps operate in class AB mode with output of up to 250wpc (for the M-80). But, if you engage the "Class A" switch, the amp will operate in Class A mode to approximately 30wpc (for the M-80), then automatically go to AB mode for >30wpc.
The downside is, of course, the amps run much hotter with the "Class A" switch engaged.
I have some Yamaha amplifiers (M-80 and M-40) that have "Class A" switches on them.
Normally, the amps operate in class AB mode with output of up to 250wpc (for the M-80). But, if you engage the "Class A" switch, the amp will operate in Class A mode to approximately 30wpc (for the M-80), then automatically go to AB mode for >30wpc.
The downside is, of course, the amps run much hotter with the "Class A" switch engaged.