These sit in different size classes, so this is not a straight ranking comparison. The Marshall Kilburn III ranks #41 of 97 large speakers by sound quality at $379.99; the Marshall Bromley 750 ranks #12 of 12 large party speakers by sound quality at $999.95.
The Marshall Kilburn III is the lighter option. Spacious soundstage with broad stereo dispersion from Marshall’s True Stereophonic multi-driver layout, delivering warm, room-filling sound with 45Hz bass extension. At 6.3 lbs (2.85 kg) it weighs much less than the Marshall Bromley 750 at 52.7 lbs (23.9 kg). The catch: Noticeable dips in the midrange compromise frequency response neutrality, making vocals and acoustic instruments sound somewhat recessed or muffled compared to more linear competitors like the JBL Xtreme 4 unless the bass dial is dialed back.
What the Marshall Bromley 750 does well: 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. Watch for: Not as deep bass as the JBL Partybox 330 or JBL Partybox 720.
Buy the Marshall Kilburn III at $379.99 for a large speaker, or the Marshall Bromley 750 at $999.95 for a large party speaker instead.
Looking for alternatives? See the complete Portable Bluetooth rankings.
Specifications Side By Side
| Marshall Kilburn III | Marshall Bromley 750 | |
|---|---|---|
| Price | $379.99 | $999.95 |
| Ranked | #41 of 97 in Large Size Portable Bluetooth Speakers | #12 of 12 in Large Party Size Portable Bluetooth Speakers |
| Amplifier Power | 50W | 400W |
| App | Yes | Yes (Marshall Bluetooth app) |
| Aux Input | Yes | Yes (3.5mm, RCA) |
| Bass Extension (-10dB) | 45Hz | - |
| Battery Life | 50 hours (Manufacturer specified) | 40+ hours (Manufacturer specified) |
| Bluetooth | Yes | Yes |
| Bluetooth Codecs | SBC, AAC | SBC, AAC, LC3 |
| Bluetooth Version | 5.3 | 5.3 |
| Built-in Microphone | No | No |
| Digital Aux Input | No | Yes (USB-C) |
| Dimensions | 10.7” x 5.9” x 6.7” (272 x 150 x 170 mm) | 16.3” x 25.7” x 14” (413 x 652 x 355 mm) |
| Drivers | 1x 4” woofer + 2x 2” full-range drivers | 2x 10” woofers, 2x 5.25” mid-ranges, 2x 1” tweeters, 2x 0.8” tweeters |
| EQ | Yes | Yes |
| Frequency Response | 45Hz - 20kHz | 20Hz - 20kHz (Manufacturer specified) |
| IP Rating | IP54 | IP54 |
| Maximum SPL | 91dB | - |
| Omnidirectional | No | Yes |
| Party Mode | Yes (Auracast) | Yes (Auracast) |
| Power Bank | Yes | Yes (USB-C) |
| Power Input | USB-C | USB-C |
| Stereo | Yes | Yes |
| Strap | Yes (built-in strap) | No |
| TWS | Yes | No |
| Weight | 6.3 lbs (2.85 kg) | 52.7 lbs (23.9 kg) |
| Guitar Input | - | Yes |
| Microphone Input | - | Yes (2x XLR/6.35mm combo) |
| XLR Input | - | Yes (2x combo) |
| USB Playback | - | No |
| Wi-Fi | - | No |
| Removable Battery | - | Yes |
| Charging Time | - | 3.5 hours |
| Lights | - | Yes |
Related Speaker Comparisons
How Marshall Kilburn III compares with other leading options:
- JBL Xtreme 5 vs Marshall Kilburn III
- Tribit Stormbox Lava vs Marshall Kilburn III
- Brane X vs Marshall Kilburn III
- Soundcore Boom 2 vs Marshall Kilburn III
- Marshall Stockwell II vs Marshall Kilburn III
Prices on this page were last checked October 2, 2026 at 10:18 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.
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The Two Speakers In Full
Marshall Kilburn III: $379.99 Amazon eBay
Older model: the Marshall Kilburn II (ranked lower, rated 3.8/5).
Pros: Spacious soundstage with broad stereo dispersion from Marshall’s True Stereophonic multi-driver layout, delivering warm, room-filling sound with 45Hz bass extension. Independent physical bass and treble dials allow quick tonal adjustments on the fly, backed by app-based EQ and placement compensation. Battery life is outstanding at up to 50+ hours with USB-C power-bank charging, IP54 splash resistance, 3.5mm aux input, and Bluetooth 5.3 with Auracast broadcast support. Measured bass extension of 45Hz (-10dB).
Cons: Noticeable dips in the midrange compromise frequency response neutrality, making vocals and acoustic instruments sound somewhat recessed or muffled compared to more linear competitors like the JBL Xtreme 4 unless the bass dial is dialed back. Kilburn II retains slightly punchier perceived loudness at maximum volume due to a more aggressive V-shaped contour. At 2.85 kg with only IP54 splash resistance, it is heavy and cannot withstand water immersion. Lacks a built-in microphone and LDAC codec support.
Full Marshall Kilburn III review and specifications →
| Amplifier Power | 50W |
|---|---|
| App | Yes |
| Aux Input | Yes |
| Bass Extension (-10dB) | 45Hz |
| Battery Life | 50 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC, AAC |
| Bluetooth Version | 5.3 |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 10.7” x 5.9” x 6.7” (272 x 150 x 170 mm) |
| Drivers | 1x 4” woofer + 2x 2” full-range drivers |
| EQ | Yes |
| Frequency Response | 45Hz - 20kHz |
| IP Rating | IP54 |
| Maximum SPL | 91dB |
| Omnidirectional | No |
| Party Mode | Yes (Auracast) |
| Power Bank | Yes |
| Power Input | USB-C |
| Stereo | Yes |
| Strap | Yes (built-in strap) |
| TWS | Yes |
| Weight | 6.3 lbs (2.85 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Marshall Kilburn III vs Marshall Kilburn II
- Marshall Kilburn III vs JBL Xtreme 4
- Marshall Kilburn III vs Ultimate Ears Everboom
- Marshall Kilburn III vs W-King T9
- Marshall Kilburn III vs Marshall Middleton
- Marshall Kilburn III vs Devialet Mania
- Marshall Kilburn III vs Marshall Middleton II
- Marshall Kilburn III vs Sony ULT Field 5
- See all 31 comparisons
Marshall Bromley 750: $999.95 Amazon eBay
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 →
| Amplifier Power | 400W |
|---|---|
| App | Yes (Marshall Bluetooth app) |
| Aux Input | Yes (3.5mm, RCA) |
| Battery Life | 40+ hours (Manufacturer specified) |
| Bluetooth | Yes |
| 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) |
| 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 |
| Lights | Yes |
| Microphone Input | Yes (2x XLR/6.35mm combo) |
| Omnidirectional | Yes |
| Party Mode | Yes (Auracast) |
| Power Bank | Yes (USB-C) |
| Power Input | USB-C |
| Removable Battery | Yes |
| Stereo | Yes |
| Strap | No |
| TWS | No |
| USB Playback | No |
| Weight | 52.7 lbs (23.9 kg) |
| Wi-Fi | No |
| XLR Input | Yes (2x combo) |
- Links
- Reviews, Comparisons and Sound Samples
- Joy & Oluv’Sone: Marshall Bromley 750 vs JBL Partybox 720 - outdoor test More from Oluv’Sone →
- Storytripper HD: W-King T12 vs Marshall Bromley 750 More from storytripperhd →
- Danny Pops: I Finally Got The Marshall Bromley 750 Everyone Wanted More from DannyPops →
- 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
- Head-to-Head Comparisons
- Marshall Bromley 750 vs Sony SRS-XV900
- Marshall Bromley 750 vs Sony ULT Tower 10
- Marshall Bromley 750 vs Sony ULT Tower 9
- Marshall Bromley 750 vs Teufel Rockster
- Marshall Bromley 750 vs JBL Partybox 520
- Marshall Bromley 750 vs JBL Partybox 710
- Marshall Bromley 750 vs JBL Partybox 720
- Marshall Bromley 750 vs Teufel Rockster 2
- See all 24 comparisons