The Stanmore 3 is a mains-powered speaker with a 2.1 channel setup (50W Class D amp for the woofer, and 2x15W for the tweeters), supporting Bluetooth 5.2 with LE Audio readiness and custom EQ control via the app or its physical knobs. It doesn’t have a battery—this one’s meant to live on a shelf. The JBL Xtreme 4, meanwhile, is fully portable with a 24-hour battery life, Bluetooth 5.3 with Auracast support, dual woofers and dual tweeters, and IP67 dust and water resistance. It even works as a power bank via USB-C. So while the Stanmore 3 leans toward refined indoor listening with power and clarity (no need to worry about recharging), the Xtreme 4 is built for on-the-go bass-heavy blasting with rugged durability and battery flexibility.
Comparing the Specs
The Stanmore 3 is a stationary speaker powered by AC, so there’s no internal battery. It uses a three-class D amplifier setup—one 50-watt amp for the woofer and two 15-watt amps for the tweeters. The frequency response runs from 45Hz to 20kHz, which gives it a strong low-end presence for a speaker its size. It supports Bluetooth 5.2 and is ready for LE Audio, which is forward-looking but not fully usable yet unless you’ve got compatible devices. What I appreciate is the classic analog control layout on top—separate knobs for volume, bass, and treble—which lets me tweak the tone directly without relying on the app.
The JBL Xtreme 4 on the other hand is a battery-powered speaker rated for 24 hours of playtime, using a USB-C port for charging and even doubling as a power bank. It runs on Bluetooth 5.3 with support for Auracast, which is a nice step up if you want to link up multiple speakers easily. The output is driven by two woofers and two tweeters, but JBL doesn’t list wattage in as much detail—the sound is definitely louder and more bass-heavy when outdoors though. It’s also IP67 rated, meaning it’s fully waterproof and dustproof, which makes it the more travel-friendly choice. In my hands, the Xtreme 4 feels like a tank with a practical strap for carrying, while the Stanmore 3 looks and feels like something I’d never want to move from its place in the living room.
Table Comparison
| Specification | Marshall Stanmore III | JBL Xtreme 4 |
| Power Output | 80W total: 50W Class D amplifier for the woofer and two 15W Class D amplifiers for the tweeters. | AC mode: 2 x 30W RMS woofers + 2 x 20W RMS tweeters (total 100W). Battery mode: 2 x 20W RMS woofers + 2 x 15W RMS tweeters (total 70W). |
| Frequency Response | 45 Hz – 20,000 Hz. | 44 Hz – 20,000 Hz. |
| Bluetooth Version | Bluetooth 5.2, ready for Bluetooth LE Audio. | Bluetooth 5.3 with Auracast support. |
| Battery Life | Not applicable (requires AC power). | Up to 24 hours of playtime, plus 6 hours with Playtime Boost. |
| Charging Time | Not applicable. | Approximately 3.5 hours. |
| Water/Dust Resistance | None. | IP67 rated (dustproof and waterproof). |
| Connectivity Options | Bluetooth, 3.5 mm input, RCA input. | Bluetooth, USB-C (audio/power), supports powerbank functionality. |
| Dimensions (W x H x D) | 350 x 203 x 188 mm (13.78 x 8.00 x 7.40 in). | 297 x 149 x 141 mm (11.7 x 5.9 x 5.6 in). |
| Weight | 4.25 kg (9.37 lbs). | 2.1 kg (4.63 lbs). |
| Additional Features | Analog controls for volume, bass, and treble; Placement Compensation; Dynamic Loudness; Marshall Bluetooth app support. | AI Sound Boost; Auracast multi-speaker connection; built-in powerbank; JBL Portable app with EQ presets; Playtime Boost feature. |
Sound Comparison
The first thing I noticed when listening to both the Marshall Stanmore 3 and the JBL Xtreme 4 was how differently they treat the low end and bass frequency ranges. Testing with “Nikes” by Frank Ocean, the Stanmore 3 brought out this deep warmth in the bass that felt more textured and restrained. It didn’t overwhelm the mids or the upper frequencies. The 50-watt Class D woofer and two 15-watt tweeters gave it this full-room sound without sounding bloated. Vocals came through clearly even when I nudged the bass knob up just a little (that physical control really helps when dialing in the tone). The stereo spread was surprisingly wide for a single-unit speaker, likely due to its angled tweeter waveguides, and I appreciated the detail it pulled out of the track’s layered production.
Switching to the JBL Xtreme 4 with “Titanium” by David Guetta and Sia, I could tell this speaker was built to be felt more than analyzed. There’s a punchier, more forward bass presence here—especially when outdoors or in bigger open rooms. The Xtreme 4 has two woofers and two tweeters pushing a combined 100 watts in AC mode and 70 watts on battery, so it has real power when it needs to. But compared to the Stanmore 3, it’s more aggressive in the way it pushes lows and highs. In tracks like “Lose Yourself to Dance” by Daft Punk, the kick drum and bass guitar felt energetic but a bit more compressed. I didn’t get the same air or separation in the mids—vocals felt closer to the surface, which makes sense for a speaker designed for outdoor playback.
I tried both speakers with “Don’t Know Why” by Norah Jones to see how they handle softer, acoustic tracks. The Stanmore 3 gave me a smoother, more relaxed presentation. Her voice felt centered and organic, with just enough sparkle on the piano to bring out the emotion of the song. With the JBL Xtreme 4, the same track felt brighter and more immediate, but the subtleties in her vocal dynamics didn’t land the same way. Overall, the Stanmore 3 delivers a more refined and detailed sound ideal for indoor listening and critical ears, while the Xtreme 4 throws more energy into the room and thrives when the priority is impact, not nuance.
Design Comparison
The Marshall Stanmore 3 design taps into that vintage amplifier vibe—textured vinyl wrap, brass-colored knobs, and the script logo that feels more rock ‘n’ roll than tech gadget. It’s a fairly heavy unit at 4.25 kg and doesn’t pretend to be portable. The build feels dense and solid, and there’s a physicality to it that’s rare in most Bluetooth speakers. I actually like how the knobs for volume, bass, and treble give me a tactile connection to the sound. The cabinet houses a 50-watt woofer and two 15-watt tweeters, and the placement of the tweeters with custom waveguides is a quiet nod to performance-driven design. This is something I’d keep on a bookshelf or a side table—it looks like part of the decor but built with the weight of a real audio system.
The JBL Xtreme 4 is designed for outdoor use and is rugged and waterproof. It’s shaped like a barrel with passive radiators on both sides, wrapped in durable fabric mesh. It weighs 2.1 kg which makes it far easier to carry around, and the detachable strap (with a built-in bottle opener) makes it pretty obvious that it’s aimed at outdoor use. The IP67 rating means it’s waterproof and dustproof, so I’ve had no problem tossing it in a bag or even using it near the pool. The build feels practical and tough rather than elegant—it’s more about surviving drops and splashes than blending into a room. While it doesn’t give the same sense of polish or finesse as the Stanmore 3, it’s clearly engineered for mobility and wear.
The Stanmore 3 feels like something I’d leave plugged in permanently and use as home as a solid fixture in my space with a focus on aesthetics and acoustic control. The Xtreme 4, on the other hand, is the kind of speaker I’d grab without thinking if I were heading out for the weekend. It trades in the elegance of materials for weatherproofing and battery life. In use, both feel sturdy and well-built, but the experience of interacting with them—the weight, the textures, the intent—feels completely different.
The Verdict?
Personally, I would go with the Marshall Stanmore 3 if I were choosing a speaker for a fixed spot at home. The sound is just more refined—it feels fuller, more balanced, and gives me room to really hear the layers in a track, especially when listening to softer or more detailed music like Norah Jones or Bon Iver. I like having physical knobs to dial in bass and treble directly, and the weight and design make it feel like a proper part of my setup. It doesn’t have a battery, and there’s no water resistance, but for a speaker that’s meant to live in one place and deliver high-quality sound all day, it does exactly what I want. The Bluetooth 5.2 with LE Audio support also gives it a bit of future-proofing if that standard gains traction.
That said, if I were looking for something to take on trips, use outside, or throw into a party setting, I think the JBL Xtreme 4 is hard to beat. It’s got serious volume, deeper bass for outdoor listening, and the IP67 rating means I never worry about where I’m putting it. The 24-hour battery life plus the built-in powerbank is genuinely useful on the go. But in terms of pure listening experience and design that complements a living space, the Stanmore 3 hits a more personal note for me. Overall, I’d say the Stanmore 3 is the better speaker if you care most about detail and sound quality at home, while the Xtreme 4 is the better all-around portable speaker if you are looking for a speaker to take outdoors or by the beach.