Sound quality: Ion-Audio's AquaSport Max had Fair overall sound quality - this model has sonic shortcomings that leave a lot to be desired when listening to music but don't rule it out for dialog. With the custom EQ set for the most even tonal balance, bass has good impact, but is a bit boomy and the deep bass is lacking. Midrange is grainy, hazy and a touch nasal. Treble is a bit prominent and sizzly, somewhat smeared, and the upper treble is muted. Does a so-so job of recovering room ambience and is somewhat congested. There is no significant difference between Bluetooth and Aux inputs. When two units are combined to form a stereo pair, the sound stage can be made wider depending on placement. Provides a decent volume level in a medium sized room. Testing note: According to the User Guide (https://www.ionaudio.com/aquasport-max - see "what's included" section and click on "User Guide" link) this model will shut down after 15 minutes when there is no Bluetooth connection or no audio signal was received when battery operated; However, during our tests all three of our test samples intermittently shut off prematurely (after 2 to 5 min) when there was a Bluetooth connection but no audio was being streamed.
