@joelepo wrote:
I have a McIntosh 402, rated 400 watts continuous per channel. If I use it to drive a pair of Klipshorns or LaScala [specified to handle 100 watts continuous] or similar high-efficiency speakers, do I risk damage to such speakers?
The La Scala’s are just around or slightly above 100dB’s measured sensitivity, and so would be very loud even with limited power supplied by the McIntosh; practically you likely won’t get to where your speakers are challenge thermally let alone mechanically, whereby the power in reserve will come in handy with loads of headroom (which is a good thing). However, something tells me the La Scala’s thrive on tube-based amps, preferably moderate to higher powered variants, so that might be worth experimenting with.
With inefficient and passively configured speakers in general (and most are), I’d recommend at least double the amp output power of the speaker’s long term max. power handling capacity. Less SPL requirements/shorter listening distance/more lively damped rooms can do with less amp output power.
Efficient and typically passively configured speakers of yore/vintage origins or inspired (with lower to moderate power handling) seem to thrive on and get by with low powered amps, tube-based in particular, whereas more modern and pro segment high efficiency speaker designs with larger voice coils and stiffer suspensions like to be fed by high powered SS amps - they simply come better and more assuredly to life this way, not least actively. Both approaches have their strengths; the former can come across seemingly a bit more lively and with more character, while the latter has the more solid and, to my ears, "neutral" and resolved imprinting. I prefer the latter camp for a variety of reasons, but I can appreciate either approach.