the mc402 is not meant to be ran as a monoblock, the only current 2 channel amp mcintosh makes that's meant to be ran as a monoblock (bridged) is the mc252, what your thinking of doing with 2 mc402's is meant for vertical biamping plus if you run your amps hard while pushing 4ohms to an 8ohm speaker the amps will get roasting hot & quickly go into protection mode (been there & done that :(
i had the mc402 & the mc252 at the same time & i thought both amps were so close in performance that i ended up keeping the mc252 over the 402, i then added a 2nd mc252 & ran them both bridged as monoblocks & the performance was excellent but still not like the mc501's.
i have ran a ton of mcintosh 2 channel amps as monoblocks & i liked them too but none compared to the mc501's or mc1201's,i still havnt tried the mc1000's so i cant comment on them.
the better move would be to sell your mc402 & upgrade to the mc501's instead,if you bought your mc402 used at $3,500 & found another mc402 for the same price you would still have 7k into the pair & mc501's can be had for less than that brand spankin new .
mike.
i had the mc402 & the mc252 at the same time & i thought both amps were so close in performance that i ended up keeping the mc252 over the 402, i then added a 2nd mc252 & ran them both bridged as monoblocks & the performance was excellent but still not like the mc501's.
i have ran a ton of mcintosh 2 channel amps as monoblocks & i liked them too but none compared to the mc501's or mc1201's,i still havnt tried the mc1000's so i cant comment on them.
the better move would be to sell your mc402 & upgrade to the mc501's instead,if you bought your mc402 used at $3,500 & found another mc402 for the same price you would still have 7k into the pair & mc501's can be had for less than that brand spankin new .
mike.