There is a wide range of what is consdered a Horn speaker, we like to have front horn loaded from 120hz up.
At these frequencies one amplifier will make most of the music through the horn and given the inherent lower sensibility of the bass systems we use a separate amplifier for bass on most of our systems. For bass my personal favorite is ClassD, it seems to blend better with Single Ended tube amplifers running the horns from 100 hz up.
We have used almost every type of amplifier on our horn speakers and all sounded fantastic, given the high sensibility the amplifier will only be using the "First watt" it generates which is said to be the cleanest one. This makes horn speakers a fair ground to test any amplifier against each other without power limitations. I can tell you that a 2 watt amp can have more dynamic prowess than a 400 watt amp, and that a Class D amp can have sweeter highs than tubes, though for most class D highs are unbearable if the design is not top notch. Solid State Class A amps have a lot of detail, but Single Ended amps do a reconstruction of instruments that is more believable than SS, some of out favorite of all time amps are OTL. So take your pick!
At these frequencies one amplifier will make most of the music through the horn and given the inherent lower sensibility of the bass systems we use a separate amplifier for bass on most of our systems. For bass my personal favorite is ClassD, it seems to blend better with Single Ended tube amplifers running the horns from 100 hz up.
We have used almost every type of amplifier on our horn speakers and all sounded fantastic, given the high sensibility the amplifier will only be using the "First watt" it generates which is said to be the cleanest one. This makes horn speakers a fair ground to test any amplifier against each other without power limitations. I can tell you that a 2 watt amp can have more dynamic prowess than a 400 watt amp, and that a Class D amp can have sweeter highs than tubes, though for most class D highs are unbearable if the design is not top notch. Solid State Class A amps have a lot of detail, but Single Ended amps do a reconstruction of instruments that is more believable than SS, some of out favorite of all time amps are OTL. So take your pick!