Audio Pro A28, A36 & A48 frequency response measurements
Added 2022-12-08 12:19:24 +0000 UTCI performed some measurements of all 3 Audio Pro speakers, as usual outdoors from a distance of 50cm. I also did some control measurements from 1m, but they looked more or less the same with the exception of some increased ground influence creeping in. I measured without and with cover (purple) to demonstrate the influece on treble.
You can see that the A36 has a very weird transition from bass to mids, which probably is the reason for the hollow character that we noticed from my recent videos. It seems to have a smoother treble response with mounted cover, while the A48 gets the 8khz area pushed even more, which probably is the reason for the slightly grainy treble character. The A48 would have the most even response if not that bump between 300-400Hz. Apart from less bass extension than the bigger ones, and less bass overall, it would have the most even response with exception of the slight dip at 8khz which gets pronounced even more with the cover mounted, at the same time the dip shifts up and becomes broader. Off axis the 8khz peak smoothens out, but overall treble response remains rather busy.
Neither of them is really "flat", although I think that the A48 with 2 correcting filters for the 350hz area and the 8khz peak would offer the best performance.
