Short answer: the B&O Beolit 20. It ranks #33 of 75 boombox speakers by sound quality at $599.99; the Diamondboxx M3 ranks #53 and costs $700, so there is little reason to consider the other one.
What the Diamondboxx M3 offers: An unusually compact 5kg high-output boombox, with a claimed 200W RMS Class A/B amplifier, 114dB maximum level, active crossovers and a choice of large battery packs. It has aux input, USB-C power and TWS pairing, while the aluminum heat sink is designed to sustain loud playback without thermal shutdown. Watch for: Despite its output, bass does not reach as deep as the best large portables and can distort when pushed hard. The treble-forward tuning can sound aggressive, there is no app or EQ to correct it, and the lack of a water rating makes it a poor match for poolside or rough-weather use.
What the B&O Beolit 20 offers: B&O Beolit 20 uses 2x 30mm tweeters + 2x 40mm mid-range + 1x 60mm woofer + dual passive radiators. Its 2.7 kg, claimed 8 hours (Manufacturer specified) battery life, IPX4 protection, aux input, up to 93dB and mono playback make it a practical option for its intended room or portable use. Watch for: Bass is limited by its 45Hz specification.
Buy the B&O Beolit 20. It ranks higher for sound quality than the Diamondboxx M3 and costs less, which settles it without a real tradeoff to make.
There is a real battery-life gap here: the Diamondboxx M3 is rated for 40 hours, the B&O Beolit 20 only 8 hours.
If water resistance matters to you, the B&O Beolit 20 at IPX4 (splashing) holds up far better than the Diamondboxx M3 at no water resistance.
Want more options? Browse the full Portable Bluetooth rankings.
Specifications Side By Side
| Diamondboxx M3 | B&O Beolit 20 | |
|---|---|---|
| Price | $700 | $599.99 |
| Ranked | #53 of 75 in Boombox Size Portable Bluetooth Speakers | #33 of 75 in Boombox Size Portable Bluetooth Speakers |
| Aux Input | Yes | Yes |
| Battery Life | 40 hours (Manufacturer specified) | 8 hours (Manufacturer specified) |
| IP Rating | None | IPX4 |
| Stereo | Yes | No |
| Omnidirectional | No | Yes |
| Weight | 11 lbs (5 kg) | 6 lbs (2.7 kg) |
| Bluetooth Codecs | SBC | SBC |
| App | No | Yes (Bang & Olufsen app) |
| EQ | No | Yes (App EQ) |
| TWS | Yes | Yes |
| Party Mode | No | No |
| Power Bank | No | Yes (USB-C) |
| USB Playback | No | No |
| Built-in Microphone | No | Yes |
| Power Input | USB-C | USB-C |
| FM Tuner | No | - |
| Amplifier Power | 200W RMS / 400W peak | 240W peak |
| Dimensions | 14.7" x 9" x 8" (373.4 x 228.6 x 203.2 mm) | 5.3" x 9.1" x 7.4" (135 x 230 x 189 mm) |
| Drivers | 3" woofer + tweeter array | 2x 30mm tweeters + 2x 40mm mid-range + 1x 60mm woofer + dual passive radiators |
| Digital Aux Input | No | No |
| Bass Extension (-10dB) | - | 45Hz |
| Maximum SPL | - | 93dB (Manufacturer specified) |
Related Speaker Comparisons
More worthwhile head-to-heads for B&O Beolit 20:
- B&O Beolit 20 vs Earfun Uboom X
- Tribit Stormbox Blast vs B&O Beolit 20
- JBL Partybox Encore 2 vs B&O Beolit 20
- JBL Partybox Encore Essential 2 vs B&O Beolit 20
- JBL Partybox Encore vs B&O Beolit 20
Prices on this page were last checked September 16, 2026 at 12:41 AM 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
Diamondboxx M3: $700 eBay
Pros: An unusually compact 5kg high-output boombox, with a claimed 200W RMS Class A/B amplifier, 114dB maximum level, active crossovers and a choice of large battery packs. It has aux input, USB-C power and TWS pairing, while the aluminum heat sink is designed to sustain loud playback without thermal shutdown.
Cons: Despite its output, bass does not reach as deep as the best large portables and can distort when pushed hard. The treble-forward tuning can sound aggressive, there is no app or EQ to correct it, and the lack of a water rating makes it a poor match for poolside or rough-weather use.
Full Diamondboxx M3 review and specifications →
| Amplifier Power | 200W RMS / 400W peak |
|---|---|
| App | No |
| Aux Input | Yes |
| Battery Life | 40 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Built-in Microphone | No |
| Digital Aux Input | No |
| Dimensions | 14.7" x 9" x 8" (373.4 x 228.6 x 203.2 mm) |
| Drivers | 3" woofer + tweeter array |
| EQ | No |
| FM Tuner | No |
| IP Rating | None |
| Omnidirectional | No |
| Party Mode | No |
| Power Bank | No |
| Power Input | USB-C |
| Stereo | Yes |
| TWS | Yes |
| USB Playback | No |
| Weight | 11 lbs (5 kg) |
- Reviews, Comparisons and Sound Samples
- No independent measurement review is linked for this model; it is ranked from hands-on listening and comparison against similarly priced speakers.
- Head-to-Head Comparisons
- Diamondboxx M3 vs W-King D10
- Diamondboxx M3 vs Demerbox DB2
- Diamondboxx M3 vs Turtlebox Grande
- Diamondboxx M3 vs Bumpboxx Flare 6
- Diamondboxx M3 vs EcoXGear Defender
- Diamondboxx M3 vs JBL Partybox On the Go
- Diamondboxx M3 vs Onn Medium Party Speaker Gen 2
- Diamondboxx M3 vs Marshall Tufton
- See all 44 comparisons
B&O Beolit 20: $599.99 Amazon eBay
Pros: B&O Beolit 20 uses 2x 30mm tweeters + 2x 40mm mid-range + 1x 60mm woofer + dual passive radiators. Its 2.7 kg, claimed 8 hours (Manufacturer specified) battery life, IPX4 protection, aux input, up to 93dB and mono playback make it a practical option for its intended room or portable use. Measured bass extension of 45Hz (-10dB).
Cons: Bass is limited by its 45Hz specification.
Full B&O Beolit 20 review and specifications →
| Amplifier Power | 240W peak |
|---|---|
| App | Yes (Bang & Olufsen app) |
| Aux Input | Yes |
| Bass Extension (-10dB) | 45Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth Codecs | SBC |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 5.3" x 9.1" x 7.4" (135 x 230 x 189 mm) |
| Drivers | 2x 30mm tweeters + 2x 40mm mid-range + 1x 60mm woofer + dual passive radiators |
| EQ | Yes (App EQ) |
| IP Rating | IPX4 |
| Maximum SPL | 93dB (Manufacturer specified) |
| Omnidirectional | Yes |
| Party Mode | No |
| Power Bank | Yes (USB-C) |
| Power Input | USB-C |
| Stereo | No |
| TWS | Yes |
| USB Playback | No |
| Weight | 6 lbs (2.7 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Joy & Oluv’Sone: B&O Beolit 20 vs Earfun UBoom X - everything fake? More from Oluv’Sone →
- Joy & Oluv’Sone: $600 premium Bluetooth speaker vs $115 cheapo UBoom X
- techkiste.net: B&O Beolit 20 vs Vifa Copenhagen 2.0 sound-comparison with different music-genres
- Oluv Patreon: B&O Beolit 20 - frequency response measurements
- Head-to-Head Comparisons