Short answer: the Partybox 520 if you want JBL’s app, EQ, and lightshow at a lower price; the Bromley 750 if all-day battery life and even room coverage matter more. These rank #11 and #6 out of 11 large-party speakers, at $1299.99 and $799.95, with the Bromley 750 costing $500.04 more.
Battery life is the biggest gap here. The Bromley 750 is rated for 40-plus hours against the Partybox 520’s 15 - currently the biggest battery-powered JBL - despite the two being rated at the same 400W output. The Bromley 750 also disperses sound more evenly in every direction, where JBL’s Partybox line tends to fire mostly forward.
The Partybox 520 answers with tuning control and value. It has a proper app with a 5-band EQ and Auracast pairing, while the Bromley 750 only offers basic bass and treble sliders - and its own notes flag a frequency response that isn’t great, with some midrange peaks. The Partybox 520 also costs noticeably less.
Both are wheeled, handle-equipped party speakers with guitar and karaoke-style mic inputs, and the Bromley 750 adds true XLR-level connectivity the Partybox 520 doesn’t match.
Buy the Partybox 520 for the lower price and real EQ control. Buy the Bromley 750 if the much longer battery and even dispersion are worth the extra cost to you.
If sound quality matters at all to you, skip the Marshall Bromley 750. It ranks near the bottom of the 11 large party speakers, so look higher up the list instead.
If battery life is a priority, the Marshall Bromley 750 is rated for 40 hours versus 15 hours for the JBL Partybox 520.
Specifications Side By Side
| Marshall Bromley 750 | JBL Partybox 520 | |
|---|---|---|
| Price | $1299.99 | $799.95 |
| Ranked | #11 of 11 in Large Party Size Portable Bluetooth Speakers | #6 of 11 in Large Party Size Portable Bluetooth Speakers |
| Aux Input | Yes (3.5mm, RCA) | Yes |
| Battery Life | 40+ hours (Manufacturer specified) | 15 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC, AAC, LC3 | SBC |
| Guitar Input | Yes | Yes |
| IP Rating | IP54 | IPX4 |
| Microphone Input | Yes (2x XLR/6.35mm combo) | Yes (Karaoke mode with echo effect) |
| Power Bank | Yes (USB-C) | Yes (USB-C) |
| Power Input | USB-C | AC Power cord |
| Weight | 52.7 lbs / 23.9 kg | 56.2 lbs / 25.5 kg |
| XLR Input | Yes (2x combo) | - |
| App | Yes (Marshall Bluetooth app) | Yes |
| Built in Microphone | No | No |
| EQ | Yes | Yes (5 band) |
| Party Mode | Yes (Auracast) | Yes (Auracast) |
| Stereo | Yes | Yes |
| TWS | No | Yes |
| USB Playback | No | Yes |
| Wifi | No | No |
| Bluetooth Version | 5.3 | 5.4 |
| Dimensions | 16.3" x 25.7" x 14" (413 x 652 x 355 mm) | 16.3" x 30.3" x 14.5" (415 x 769 x 369 mm) |
| Drivers | 2x 10" woofers, 2x 5.25" mid-ranges, 2x 1" tweeters, 2x 0.8" tweeters | 2x 7.5" woofer, 2x 1" dome tweeter |
| Output Power | 400W | 400W |
| Digital Aux Input | Yes (USB-C) | No |
| Removable Battery | Yes | Yes |
| Charging Time | 3.5 hours | - |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) | - |
| Discontinued | No | - |
The Two Speakers In Full
Marshall Bromley 750: $1299.99 Amazon
Pros: Much wider, more consistent off-axis dispersion than the JBL Partybox 720, which only fires forward - the Marshall’s standout feature, sounding about the same from any angle.
Cons: Not as deep bass as the JBL Partybox 330 or JBL Partybox 720. Not a great frequency response overall, with some midrange peaks. Only basic bass/treble controls, no full custom EQ like the JBL Partybox 720’s app. Default bass (dynamic mode) is overdone out of the box and needs trimming.
Full Marshall Bromley 750 review and specifications →
| App | Yes (Marshall Bluetooth app) |
|---|---|
| Aux Input | Yes (3.5mm, RCA) |
| Battery Life | 40+ hours (Manufacturer specified) |
| Bluetooth Codecs | SBC, AAC, LC3 |
| Bluetooth Version | 5.3 |
| Built in Microphone | No |
| Charging Time | 3.5 hours |
| Digital Aux Input | Yes (USB-C) |
| Dimensions | 16.3" x 25.7" x 14" (413 x 652 x 355 mm) |
| Discontinued | No |
| Drivers | 2x 10" woofers, 2x 5.25" mid-ranges, 2x 1" tweeters, 2x 0.8" tweeters |
| EQ | Yes |
| Frequency Response | 20Hz - 20kHz (Manufacturer specified) |
| Guitar Input | Yes |
| IP Rating | IP54 |
| Microphone Input | Yes (2x XLR/6.35mm combo) |
| Output Power | 400W |
| Party Mode | Yes (Auracast) |
| Power Bank | Yes (USB-C) |
| Power Input | USB-C |
| Removable Battery | Yes |
| Stereo | Yes |
| TWS | No |
| USB Playback | No |
| Weight | 52.7 lbs / 23.9 kg |
| Wifi | No |
| XLR Input | Yes (2x combo) |
As an eBay Partner, we may be compensated if you make a purchase.
- Links
- Reviews, Comparisons and Sound Samples
- Joy & Oluv’Sone: Marshall Bromley 750 vs JBL Partybox 720 - outdoor test
- Storytripper HD: W-King T12 vs Marshall Bromley 750
- Danny Pops: I Finally Got The Marshall Bromley 750 Everyone Wanted
- Oluv Patreon: JBL Partybox 720 vs Marshall Bromley 750
- Oluv Patreon: Marshall Bromley 750 - battery issues in the cold
- Oluv Patreon: Marshall Bromley 750 & Teufel Rockster Air 2 - outdoor test
- Oluv Patreon: Marshall Bromley 750 - 2nd look after update
- Oluv Patreon: Marshall Bromley 750 - first impressions
- Reddit Search for Marshall Bromley 750 Review
- Head-to-Head Comparisons
JBL Partybox 520: $799.95 Amazon Bhphotovideo
Pros: Handle and wheels are convenient. Lightshow ability. The biggest battery powered JBL currently.
Cons: Very large and heavy. Note, JBL daisychain is not compatible with any other non-JBL speaker and is possibly a fully digital signal.
Full JBL Partybox 520 review and specifications →
| App | Yes |
|---|---|
| Aux Input | Yes |
| Battery Life | 15 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.4 |
| Built in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 16.3" x 30.3" x 14.5" (415 x 769 x 369 mm) |
| Drivers | 2x 7.5" woofer, 2x 1" dome tweeter |
| EQ | Yes (5 band) |
| Guitar Input | Yes |
| IP Rating | IPX4 |
| Microphone Input | Yes (Karaoke mode with echo effect) |
| Output Power | 400W |
| Party Mode | Yes (Auracast) |
| Power Bank | Yes (USB-C) |
| Power Input | AC Power cord |
| Removable Battery | Yes |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | Yes |
| Weight | 56.2 lbs / 25.5 kg |
| Wifi | No |
As an eBay Partner, we may be compensated if you make a purchase.
- Links
- Reviews, Comparisons and Sound Samples
- Oluv Patreon: JBL Partybox 520 & 720 - indoor listening session
- Oluv Patreon: JBL Partybox 520 vs 720 - outdoor test
- Oluv Patreon: JBL Partybox 320 vs 520 - indoor listening session
- Oluv Patreon: JBL Partybox 320 vs 520 - outdoor test
- Oluv Patreon: JBL Partybox 520 vs Teufel Rockster Neo
- Oluv Patreon: W-King T12 vs JBL Partybox 520
- AudioTribe: JBL PartyBox 520 Loudness & BASS Test Will Shock You!
- GYMCADDY: JBL Partybox 720 Vs JBL Partybox 520
- AudioTribe: JBL Partybox 720 vs JBL Partybox 520 Who’s Better?
- Reddit Search for JBL Partybox 520 Review
- Head-to-Head Comparisons
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Product prices and availability were last checked August 12, 2026 at 5:33 PM UTC 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.