These are not really the same size class, and that is the honest framing here. The Marshall Acton III ranks #11 of 28 powered desktop speakers by sound quality at $298.99; the JBL Authentics 300 ranks #44 of 99 boombox speakers by sound quality at $499.95.
The case for the Marshall Acton III: Ac-powered operation and limited-stereo playback make its feature set practical for its intended room or portable use. It keeps a wired aux input, which the JBL Authentics 300 lacks.
The JBL Authentics 300 is the battery-powered pick. Integrates both Amazon Alexa and Google Assistant simultaneously (rare for smart speakers). Its battery is rated for 8 hours, while the Marshall Acton III needs an outlet. It streams over Wi-Fi as well as Bluetooth, which the Marshall Acton III cannot. It links with other speakers (Wi-Fi Multi-Room), which the Marshall Acton III cannot. The catch: Narrow sounding, bass not as deep as others.
Buy the Marshall Acton III at $298.99 if you want a powered desktop speaker. Buy the JBL Authentics 300 at $499.95 if you want a boombox speaker instead.
Still deciding? The full Powered Home rankings and Portable Bluetooth rankings cover every ranked option.
Specifications Side By Side
| Marshall Acton III | JBL Authentics 300 | |
|---|---|---|
| Price | $298.99 each | $499.95 |
| Ranked | #11 of 28 in Medium Size Powered Desktop Speakers | #44 of 99 in Boombox Size Portable Bluetooth Speakers |
| Aux Input | Yes | No |
| Battery Life | No Battery | 8 hours (Manufacturer specified) |
| IP Rating | None | None |
| Power Bank | No | No |
| Stereo | Partially (1 woofer) | Partially (1 woofer) |
| Weight | 6.3 lbs (2.85 kg) | 10.8 lbs (4.9 kg) |
| App | Yes | Yes |
| Bluetooth Codecs | SBC | SBC |
| Bluetooth Version | 5.2 | 5.3 |
| Dimensions | 10.2” x 6.7” x 5.9” (260 x 170 x 150 mm) | 13.5” x 7.7” x 7.1” (342 x 195.6 x 180.3 mm) |
| EQ | Yes (Bass/Treble) | Yes (App EQ) |
| Frequency Response | 45Hz - 20kHz (Manufacturer specified) | - |
| Inputs | Bluetooth, Aux | - |
| Drivers | 4” (midrange/woofer), 1x 4” midrange, 2x 0.75” Dome tweeters | 1” tweeter + 4” woofer + passive radiators |
| Party Mode | No | Yes (Wi-Fi Multi-Room) |
| TWS | No | Yes |
| Wi-Fi | No | Yes |
| Woofer Cabinet | ported | - |
| Amplifier Power | 60W (Woofer: 30W, Tweeters: 2x15W) | 100W |
| XLR Input | No | - |
| RCA Input | No | - |
| TRS Input | No | - |
| Optical Input | No | - |
| Coaxial Input | No | - |
| USB Input | No | - |
| HDMI Input | No | - |
| AES Input | No | - |
| Bluetooth | Yes | Yes |
| Bass Extension (-10dB) | - | 45Hz |
| Maximum SPL | - | 100dB (measured by Alan Ross Reviews) |
| Power Input | - | AC Power cable |
| Omnidirectional | - | No |
| USB Playback | - | Yes |
| Built-in Microphone | - | Yes |
| MicroSD Playback | - | No |
| Digital Aux Input | - | No |
| Voice Assistants | - | Amazon Alexa & Google Assistant (simultaneous) |
| Strap | - | No |
Related Speaker Comparisons
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Prices on this page were last checked October 14, 2026 at 2:38 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 Acton III: $298.99 each Amazon $298.99 Marshall $299.99 eBay
Newer model: the Marshall Acton IV, estimated 3.7/5, released Jul 2026. It adds party mode, AAC, LC3 and LDAC.
Older model: the Marshall Acton II (ranked lower, rated 3.5/5). See every Marshall home speakers generation.
Same family: the Marshall Stanmore III (larger model, ranked higher, rated 3.8/5) and the Marshall Woburn III (larger model, ranked higher, rated 4.1/5).
Pros: At 2.85 kg, Marshall Acton III combines 4” (midrange/woofer), 1x 4” midrange, 2x 0.75” Dome tweeters with Bluetooth, Aux. Ac-powered operation and limited-stereo playback make its feature set practical for its intended room or portable use.
Cons: Bass is limited by its 45Hz to 20kHz (Manufacturer specified) specification.
Full Marshall Acton III review and specifications →
| Released | Oct 2022 (4 years ago) |
|---|---|
| AES Input | No |
| Amplifier Power | 60W (Woofer: 30W, Tweeters: 2x15W) |
| App | Yes |
| Aux Input | Yes |
| Battery Life | No Battery |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.2 |
| Coaxial Input | No |
| Dimensions | 10.2” x 6.7” x 5.9” (260 x 170 x 150 mm) |
| Drivers | 4” (midrange/woofer), 1x 4” midrange, 2x 0.75” Dome tweeters |
| EQ | Yes (Bass/Treble) |
| Frequency Response | 45Hz - 20kHz (Manufacturer specified) |
| HDMI Input | No |
| IP Rating | None |
| Inputs | Bluetooth, Aux |
| Optical Input | No |
| Party Mode | No |
| Power Bank | No |
| RCA Input | No |
| Stereo | Partially (1 woofer) |
| TRS Input | No |
| TWS | No |
| USB Input | No |
| Weight | 6.3 lbs (2.85 kg) |
| Wi-Fi | No |
| Woofer Cabinet | ported |
| XLR Input | No |
- Links
- Reviews, Comparisons and Sound Samples
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JBL Authentics 300: $499.95 Amazon $499.95 eBay
Same family: the JBL Authentics 200 (smaller model, rated 3.7/5) and the JBL Authentics 500 (larger model, rated 4.1/5).
Pros: Integrates both Amazon Alexa and Google Assistant simultaneously (rare for smart speakers). Retro seventies design with leather and Quadrex grille. 100-watt amp, carries well with leather-trimmed handle. Rechargeable battery rated ~8 hours. Measured bass extension of 45Hz (-10dB).
Cons: Narrow sounding, bass not as deep as others. Peaky upper mids. No TWS. No IP rating. Not as loud as others. Not much battery life.
Full JBL Authentics 300 review and specifications →
| Released | Sep 2023 (3 years ago) |
|---|---|
| Amplifier Power | 100W |
| App | Yes |
| Aux Input | No |
| Bass Extension (-10dB) | 45Hz |
| Battery Life | 8 hours (Manufacturer specified) |
| Bluetooth | Yes |
| Bluetooth Codecs | SBC |
| Bluetooth Version | 5.3 |
| Built-in Microphone | Yes |
| Digital Aux Input | No |
| Dimensions | 13.5” x 7.7” x 7.1” (342 x 195.6 x 180.3 mm) |
| Drivers | 1” tweeter + 4” woofer + passive radiators |
| EQ | Yes (App EQ) |
| IP Rating | None |
| Maximum SPL | 100dB (measured by Alan Ross Reviews) |
| MicroSD Playback | No |
| Omnidirectional | No |
| Party Mode | Yes (Wi-Fi Multi-Room) |
| Power Bank | No |
| Power Input | AC Power cable |
| Stereo | Partially (1 woofer) |
| Strap | No |
| TWS | Yes |
| USB Playback | Yes |
| Voice Assistants | Amazon Alexa & Google Assistant (simultaneous) |
| Weight | 10.8 lbs (4.9 kg) |
| Wi-Fi | Yes |
- Links
- Reviews, Comparisons and Sound Samples
- JOY‘s 🎧3D🔈Audio-Show: JBL Authentics 300 - sound quality test More from Oluv’Sone →
- Oluv Patreon: JBL Authentics 300 - update
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- Alan Ross Reviews: Not quite! JBL Authentics 300 review and sound test vs Boombox 3, Encore and Stormbox Blast More from alanrossreviews →
- Storytripper HD: W-King H330 vs JBL Authentics 300 More from storytripperhd →
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