Having had a C370 powering my M80's at one time I can assure you that it will drive them well enough on its own. If you want even MORE power instead of bridging the amps and using them as mono blocks you can biamp instead using say the C370 for the mids and tweeter drivers and the C270 on the woofers. Thanks to the second preamp output on the C370 you can do this. The amplifier sections are identical in both of those amplifiers as I am sure you are well aware.

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