Short answer: the Partybox 520. At essentially the same price, it ranks #8 of 13 large party speakers against the Tower 9’s #10, and the Tower 9 does not have a clean counter-argument on price to make up the difference.
The Tower 9’s own cons are the story here. Its notes say it is not as deep of bass and loses more bass at high volume, even compared to lower end Partybox speakers, with bass dropping off a lot as you turn it up. It is also listed as not quite as loud as its own sibling, the ULT Tower 10. The 520 has no such complaint in its notes, and it is rated at 400W against the Tower 9’s 148W, driven by dual 7.5 inch woofers rather than the Tower 9’s single 12.6 inch woofer and midrange array.
Durability favors the JBL too. The 520 carries an IPX4 splash rating; the Tower 9 has no water resistance rating at all. That matters more on a speaker this size, since it is the one most likely to end up outdoors at a party.
What the Tower 9 does better: battery life is a real advantage at 25 hours against the 520’s 15, it supports AAC and LDAC over Bluetooth where the 520 is SBC only, and its 10 band EQ is finer grained than the 520’s 5 band EQ. Sony’s own listed strength for the Tower 9 is that it sounds slightly better than the ULT Tower 10, so it is not without merit as a listening device, just not one that outsells the 520 on price or output.
Buy the Partybox 520 unless you specifically need the Tower 9’s longer battery life or its wider codec support. It costs about the same, hits harder, and holds up to splashes the Tower 9 cannot survive.
Buy the Tower 9 if all-day unplugged runtime and hi-res Bluetooth codecs matter more to you than raw output and weather resistance.
Still deciding? The full Portable Bluetooth rankings cover every ranked option.
A loud battery party speaker with deep bass, wheels, a capable app EQ, and inputs for mics and instruments.
A battery powered party tower with good sound, a long battery, karaoke inputs, and a detailed app EQ.
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Specifications Side By Side
| JBL Partybox 520 | Sony ULT Tower 9 | |
|---|---|---|
| Price | $879.95 | $898.00 |
| Ranked | #8 of 13 in Large Party Size Portable Bluetooth Speakers | #10 of 13 in Large Party Size Portable Bluetooth Speakers |
| App | Yes | Yes |
| Aux Input | Yes | Yes |
| Battery Life | 15 hours (Manufacturer specified) | 25 hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC | SBC, AAC, LDAC |
| EQ | Yes (5 band) | Yes (10 band) |
| Guitar Input | Yes | Yes |
| IP Rating | IPX4 | None |
| Microphone Input | Yes (Karaoke mode with echo effect) | Yes (Karaoke mode with echo effect) |
| Party Mode | Yes (Auracast) | Yes (Auracast up to 100 speakers) |
| Power Bank | Yes (USB-C) | Yes (USB-A, 5V/1.5A) |
| Power Input | AC Power cord | AC Power cord |
| Removable Battery | Yes | No |
| TWS | Yes | Yes |
| USB Playback | Yes | Yes |
| Weight | 56.2 lbs (25.5 kg) | 65.3 lbs (29.6 kg) |
| Built-in Microphone | No | No |
| Stereo | Yes | Yes |
| Omnidirectional | No | No |
| Wi-Fi | No | No |
| Bluetooth Version | 5.4 | 5.3 |
| Dimensions | 16.3” x 30.3” x 14.5” (415 x 769 x 369 mm) | 16.1” x 35.8” x 18” (410 x 910 x 456 mm) |
| Drivers | 2x 7.5” woofer, 2x 1” dome tweeter | 7 drivers: 1x 12.6”x12.6” woofer, 2x 4.7” midrange, 2x 2” tweeter, 2x 1.6” rear tweeter |
| Amplifier Power | 400W | 148W |
| Digital Aux Input | No | No |
| Lights | Yes | Yes |
| Wheels | Yes | - |
| Strap | No | No |
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