It looks like the ohm are all over the map. The round being 32ohm, and the square being 6ohm.
Wattage for most of the small ones I am seeing is 0.5 to 0.8 W.
I understand a bit about impedance, but what would be a good fit for a proffie?
Because it’s a blaster, the bass (probably) isn’t too big of a concern, but it would be nice if it sounds good and has plenty of volume.
Those things will never happen with a small speaker.
Proffies can only output 10v peak-to-peak, so higher impedance means less watts. That may not be a problem if your speaker can’t handle the ~3 watts that a proffieboard can deliver. Impedances below 4 ohms are not supported and may potentially damage the amplifier.
Watt specifcations for small speakrs are also all over the map. They don’t consistently measure the same thing, and some lists how many watts can be delivered with a maximum TDP, while others lists how many watts are unlikely to damage the speaker…
Of the ones you listed, the PUI one seems to be the best match. 8 ohms is quite reasonable for a small speaker. At 8 ohms, a proffieboard can deliver about 1.5 watts, and the speaker has a maximum input power of 1.5 watts, which means that it should be difficult to break the speaker by adjusting the volume too high.
Cell phones do better than most small speakers. I wouldn’t go so far as to say they sound “good” though. Cell phones have a DSP that employs a range of tricks like over-driving, bass boosting and lost fundamentals to improve the sound. It may be possible to implement some of those tricks in ProffieOS, but it would probably use up a lot of cpu cycles.
We also know that the parts that surround the speaker make a big difference in sound volume and quality, but I’m not sure that anybody knows how well enough to give advice on what works and what doesn’t.