Sounds like a second 75SE is definitely worth considering. But, before
monoblocking them, why not try vertical biamping with two 75SE's; one
channel for the mid/low and the other for the tweet. Can't speak re these
amps specifically, and it sounds like Jfrech got excellent results, but it is
well documented than there are many examples of amps that when mono
blocked yield the benefits of the additional power, but also lose finesse
and purity. It may not be the case with these, but costs nothing to try first,
and is a simpler possible solution. And if you already like the sound of the
amps it can only be a step up; no risk of any losses.
monoblocking them, why not try vertical biamping with two 75SE's; one
channel for the mid/low and the other for the tweet. Can't speak re these
amps specifically, and it sounds like Jfrech got excellent results, but it is
well documented than there are many examples of amps that when mono
blocked yield the benefits of the additional power, but also lose finesse
and purity. It may not be the case with these, but costs nothing to try first,
and is a simpler possible solution. And if you already like the sound of the
amps it can only be a step up; no risk of any losses.