With these types of Bluetooth mini speakers, good sound is a relative term. Overall, they just don't sound great, they offer virtually no stereo separation, and they have their limitations as far as clarity and bass performance go. All that said, relatively speaking, the Oontz Angle sounds decent for its modest price point and size. It plays fairly loud, with a reasonable amount of detail and some bass, though not quite enough to keep it from sounding a little thin. Like most speakers of this type, it's strongest in the midrange, so it will sound best with lighter fare (less bass-heavy music) and acoustical tracks.
It doesn't sound quite as good as the $99.99 UE Mobile Boombox, though it's less than half the price (UE Mobile Boombox is a sturdier unit with a slicker look; it also plays a little louder). In terms of sound, the Oontz Angle is right there with the $49.99 Philips SoundShooter, one of our favorite tiny speakers. However, it doesn't sound as good or play as loud as the $99 JBL Flip, though the Oontz Angle does offer better battery life. I also think it sounds a touch better than the $49.99 HMDX Jam Plus, though you can pair two of those HMDX speakers to get stereo sound; however, the Oontz Angle's battery life is significantly better.
Compared with the higher-priced Oontz, the Oontz Angle doesn't offer as much bass and just sounds a little thinner overall. It's not a huge difference, but it is noticeable. In some ways that's a shame because I like the design of the Oontz Angle a bit better (perhaps Cambridge will do a slightly bigger version of the Angle in the future).
It is worth noting that you will get some distortion with this speaker (and the larger Oontz) at higher volumes, and while the speaker does have rubber feet, it may move around a bit on smooth surfaces if you play tunes with heavier bass lines at high volumes.
As noted, battery life is good. I exceeded the 10 hours of rated battery life in my tests, though I played my music at more moderate levels.
For a while Cambridge SoundWorks was selling the Oontz Angle for $49.99, but it recently shaved the price by $10, lowering it to $39.99. While it doesn't have as much bass as the $49.99 Oontz and sounds a little thinner as a result, the Angle still is one of the better values in Bluetooth speakers at $39.99 -- and I liked its design better than the Oontz's.
While I have a few gripes (Mini-USB port, bright blue light on front), overall I think most people will be happy with the Angle's performance and features at this modest price level. If you value sound quality over design, it's probably worth paying the extra $10 to get the step-up Oontz instead of this model. But if you prefer the Angle's design, save the $10.