I tried the Astrotec S60 today. They have one of the smallest cases ever, use a Knowles BA, (apparently) support AAC and SBC, and have USB-C and wireless charging compatibility.
I was attracted by the BA design and also the fact that the small case is made of metal and looks like it can be stepped on...not that I intend to step on it.
It was pretty nice. The case is the size of 3 lip balm sticks taped together in a triangle. It has a nice weight to it and definitely feels indestructible. The case uses a magnet to close, and the magnet is quite strong. It is a little hard to open the case. The buds are also held down by magnets. The case feels indestructible.
The buds themselves are made of plastic and are quite light. They look like they were made to nestle in your ear conch comfortably and block off sound that way, but the buds themselves are a little too small to fill in the whole conch, and the fit is a little shallow. The eartips on the demo were also small, so it doesn't feel super stable, but I have a feeling better eartips might fix that. They have a single super-large button, and you can press it up above your earhole, so it's not bad.
I was using my M0 to test it out, but it wouldn't connect to AAC...this happens a lot, for some reason they say AAC compatible, but it only works with an Iphone, which is frustrating. It connected fine in SBC though. That being said, I am not sure if it is because it is not a dynamic driver, but the separation was good, and I couldn't hear any typical SBC graininess. The soundstage also sounded very nice.
The sound was pretty good. It has a pretty deep far-reaching bass. Very nice slam on Killshot and a good rumble. The mids were a little recessed, but they had a huge BA sound. I am a big fan of vocals rendered by a balanced armature, so I was happy to hear that. The vocals were very clear (unlike the Earmin M2), and reminded me a little of the Etymotic HF5. I tested the highs with a few songs of Adele, and couldn't hear any graininess or sound lacking. I really regret not trying out the Foo Fighter's Everlong for cymbals, but the sound reminded me so much of the HF5 that I strongly suspect that they might be rolled off.
Overall, it was a very nice sound profile. The only thing that irks me is the AAC not working with my gear, but I've had this issue with 2 or 3 other sets of TWE and was told that some only support AAC for Iphones. I really loved those detailed vocal crystal clear mids, and they really tuned it to maximize that bass response from their Balanced Armature. I feel the recessed mids does a nice job adding to the soundstage, and there was a nice amount of air between the instruments. I might have to listen again to hear those cymbals, as muted cymbals are sometimes irritating.
The case was super nice, but maybe a little too tall. I think even though bigger, the Mavin case is more pocketable because it is thinner. I do like how indestructible the case felt though, having two young children asking me to hold them, it is not uncommon for them to accidentally kick my pockets. I'd get worried with a flimsy plastic case,