I'm building a rough-and-ready 3-way which uses the Dayton RS-52 metal dome midrange driver. I noticed that this driver has a response that reaches very close to 20kHz. It occurred to me that the RS52 might work as a tweeter. Now, there is a rather nasty peak at around 13kHz but I thought I could tame that with my DSP crossover.
So I did it. I must say that it doesn't sound half bad. I managed to suppress the peak at 1344Hz and implement as a 2-way. It is passable. There was a hint of sibilance still, but I think these would cut it a surround speakers (as suggested above). However, the real performance became evident when I implemented the 3-way design: the tweeter just added that missing sparkle and cleanness at the top. Possibly, with a boost to the upper frequencies for the 2-way and individual equalisation (matching) of the RS52s, a better performance can be achieved.
BTW, for the 2-way the crossover was LR4 at 600Hz, and the 3-way was LR4 at 600Hz and 3.5kHz.RS52 response. Light blue is raw response, black is target, red is filter response, and dark blue is final response.Total loudspeaker response of the 2-way.Response of the 3-way.
Some more info about the loudspeaker: the box and driver cutouts were originally intended for another project that was aborted, thus the hack job you see. The tweeter is an OEM unit claimed to be from the Vifa factory, and the woofer is a Super8 from ApexJr. The box is sealed, and there is some equalisation applied to the woofer to extend its response. A very quick and nasty effort.Box