Short answer: the JBL Flip 6. It ranks #13 of 179 medium speakers by sound quality (rated 4.2/5) at $79.95 and is still sold new; the EarFun Uboom Slim ranks #43 (rated 3.7/5) and is discontinued, so it is only an option used.
The JBL Flip 6 is the better-sounding, deeper-bass pick. A small, rugged speaker with very neutral sound for its size, an excellent choice for most people. Its bass reaches about 56Hz before falling 10dB, against 63Hz for the EarFun Uboom Slim. It supports AAC Bluetooth, which the EarFun Uboom Slim lacks. It has an adjustable EQ, which the EarFun Uboom Slim lacks. The catch: Some slight upper mids emphasis.
The EarFun Uboom Slim is the longer-running option. A slim, affordable waterproof stereo speaker with long battery life that doubles as a speakerphone. It is rated for 16 hours of battery against 12 for the JBL Flip 6. It keeps a wired aux input, which the JBL Flip 6 lacks. It plays in stereo from a single unit, unlike the JBL Flip 6. The tradeoff: Not as deep bass as others.
Buy the JBL Flip 6. It is rated higher for sound quality; the EarFun Uboom Slim is no longer sold new.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Prices on this page were last checked November 7, 2026 at 7:34 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
As an eBay Partner, we may be compensated if you make a purchase.
Specifications Side By Side
| JBL Flip 6 | EarFun Uboom Slim | |
|---|---|---|
| Price | $79.95 | $79 Discontinued |
| Ranked | #13 of 179 in Medium Size Portable Bluetooth Speakers | #43 of 179 in Medium Size Portable Bluetooth Speakers |
| App | Yes | No |
| Aux Input | No | Yes |
| Bass Extension (-10dB) | 56Hz | ~63Hz |
| Battery Life | 12 hours (Manufacturer specified) | 16 hours (Manufacturer specified) |
| Built-in Microphone | No | Yes |
| EQ | Yes (3 band) | No |
| IP Rating | IP67 | IPX7 |
| Bluetooth Latency | 116ms | - |
| Maximum SPL | 98dB (measured by Alan Ross Reviews) | - |
| Party Mode | Yes (PartyBoost up to 100 speakers) | - |
| Power Bank | No | - |
| Stereo | No | Yes |
| Omnidirectional | No | No |
| TWS | Yes | Yes |
| Weight | 1.2 lbs (544 g) | 1.2 lbs (560 g) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | AAC, SBC | SBC |
| Bluetooth Version | 5.1 | 5.2 |
| Dimensions | 6.9” x 2.7” x 2.8” (176 x 68 x 72 mm) | 2.6”H x 7.1”W x 2.6”D (65 x 180 x 65 mm) |
| Drivers | 44mm x 80mm woofer, 16mm tweeter | 45mm speaker drivers |
| Power Input | USB-C | USB-C |
| Amplifier Power | 30W | 20W |
| Digital Aux Input | No | No |
| Strap | Yes (built-in loop) | - |
Related Speaker Comparisons
More worthwhile head-to-heads for JBL Flip 6: