Surprisingly loud. I got mine to brighten up an 80 watt acoustic amplifier combo, this really did the job and did the job well, in fact I may have to attenuate it a little.
There is various wiring diagrams on line to help wire these things up in many different ways, while keeping them sounding good and lasting well.
I have used them before to replace "gone weak" compression horns on PA speakers, then they got so abused using them for "disco" & keyboard speakers, I was sure they'd be blown in little time, but I was wrong.
These really bring out the highs, sweet and bright and the price is nice.