Sony ULT Field 7 Review

Design

• Cylindrical form factor
• IP67 waterproof and dustproof
• Dual integrated carry handles

The ULT Field 7 is unmistakably a Sony product, sporting the company’s recent penchant for utilitarian design wrapped in premium materials. At 512 x 224 x 222mm, this is a substantial speaker that makes no apologies for its size..

The tubular chassis combines hard plastic end caps with a rugged mesh fabric wrapped around the midsection. It’s undeniably tough-looking, and the IP67 rating backs up that impression. You can submerge this thing in a metre of water for 30 minutes, and it’ll shrug off dust storms without complaint. It’s even saltwater-resistant, so beach trips won’t see it corroding into oblivion.

At 6.3kg, the ULT Field 7 is no featherweight. Sony’s provided two sturdy rubberised handles moulded into the top surface, and they’re substantial enough to inspire confidence during transport. That said, you’re not going to want to lug this thing on a country ramble. It’s a car-to-garden speaker, not a hiking companion.

The passive radiators dominating each end are impossible to miss — two large circular drivers with LED rings that illuminate during playback. They’re visually striking when the lights are active, though the effect is admittedly Marmite.

Some will love the disco vibes; others will find it naff. At least you can switch the lights off if they’re not your cup of tea.

The top control panel houses six physical buttons: power, Bluetooth pairing, play/pause, volume up/down, and the star of the show — that ULT button. They’re well-spaced and responsive, though you’ll likely default to phone controls for most functions.

Here’s where things get interesting. A flush-mounted panel on the rear hides a treasure trove of connectivity and controls. Pop it open and you’ll find a figure-eight power input (more on that annoyance later), USB-A port for device charging, 3.5mm aux input, and a 6.3mm jack for microphones or guitars. There are also dedicated controls for key adjustment (useful for karaoke), echo levels, lighting on/off, and battery care mode.

The design does have one significant Achilles heel: it’s a magnet for dust, fluff, and general detritus. Both the fabric grille and the rubberised elements seem to attract lint with supernatural efficiency. If you’re house-proud, this will drive you spare. At least the speaker can be hosed down thanks to that IP67 rating.

Features

• Dual ULT bass modes
• LDAC high-res Bluetooth
• Party Connect multi-speaker pairing
• Karaoke and guitar functionality

The ULT Field 7’s headline feature is right there in the name: ULT Power Sound. Sony’s not mucking about — this is a bass-first speaker, and those ULT modes are front and centre.

A single press of the ULT button engages ULT1, emphasising deep, subterranean bass frequencies. It’s designed for tracks with serious low-end content — think hip-hop, dubstep, Barry White. A second press switches to ULT2, which Sony describes as “powerful and punchy.” This mode boosts mid-bass for increased impact and loudness, ideal for outdoor use where low frequencies dissipate quickly.

It’s not just marketing fluff. The ULT modes genuinely transform the speaker’s character. ULT1 adds proper depth and weight, though it can overwhelm more delicate material. ULT2 is less refined but undeniably effective for getting a party started. With both modes off, the speaker adopts a more neutral profile that’s actually quite balanced for a bass-centric speaker.

Connectivity is comprehensive. Bluetooth 5.2 provides the wireless foundation, with support for SBC, AAC, and crucially, LDAC. Sony’s hi-res codec can transmit up to 990kbps at 24-bit/96kHz, significantly outperforming standard Bluetooth quality. Audiophiles will appreciate the difference, even if the ULT Field 7’s tuning isn’t exactly reference-grade.

Multipoint connection allows pairing with two devices simultaneously, handy for households with multiple phone-wielding party attendees. Fast Pair makes Android connections nearly instantaneous, though iOS users are left with standard Bluetooth pairing.

Party Connect is Sony’s answer to JBL’s (now defunct) PartyBoost. Link two ULT Field 7 speakers for proper stereo separation, or daisy-chain up to 100 compatible Sony speakers for neighbourhood-annoying volume levels. The lighting effects sync across connected speakers too, which is admittedly quite spectacular when you’ve got multiple units firing.

The karaoke and guitar functionality elevates the ULT Field 7 beyond typical party speakers. Plug a dynamic microphone into the 6.3mm jack, adjust the echo and key controls on the rear panel, and you’ve got a karaoke system ready to go. Swap the mic for a guitar and you’ve got an impromptu amp. Not something you’d record with, but perfectly serviceable for casual jamming.

Sound Field Optimization is Sony’s adaptive EQ that adjusts output based on the surrounding environment. In practice, it’s subtle and not the dramatic room correction you’d get from high-end smart speakers, but helpful for quickly adapting when you move from indoors to outdoors.

Connectivity

• Straightforward setup
• Rock-solid Bluetooth connectivity
• Versatile source options

Getting the ULT Field 7 operational takes approximately 30 seconds. Turn it on, hold the Bluetooth button, select it from your phone’s pairing menu, and you’re streaming. Sony’s Fast Pair makes Android connections even quicker — just bring your phone close and tap the notification.

Bluetooth range is excellent. I maintained a connection across approximately 12 metres with one brick wall in between, and probably could have pushed further outdoors.

The aux input provides an alternative for devices without Bluetooth, though it’s a 3.5mm jack rather than the dual RCA you’d find on some party speakers. It’ll handle phones, laptops, and MP3 players without fuss, but DJ gear with professional outputs might need adapters.

I didn’t have the opportunity to test the karaoke or guitar functionality extensively, but initial impressions are positive. The dedicated echo control provides genuine customisation rather than fixed presets, and the key adjustment buttons let you shift songs into your vocal range. It’s more capable than you’d expect from what’s ostensibly an add-on feature.

Battery

• 30 hours battery life
• Fast-charging
• Powerbank support

The speaker shipped with about 40% charge, and the supplied figure-eight power cable is frustratingly short at perhaps two feet. You’ll want to charge near an outlet unless you’ve got a spare cable knocking about. Why Sony didn’t opt for USB-C is baffling, especially given the speaker only draws 45 watts.

That battery, though, is a marathon runner. Sony claims 30 hours with ULT1 or ULT2 engaged, volume at 16 (roughly mid-level), and lights deactivated. In practice, I managed 28 hours across a week of testing with mixed volume levels and occasional light show activity. That’s genuinely impressive, comfortably outlasting the JBL Boombox 3’s 24 hours.

Variables affect battery life significantly. Activate the RGB lighting and expect to shed several hours. Push volume to maximum and you’ll drain the battery in roughly three hours – still respectable, but a fraction of the potential runtime.

Use Stamina mode (a battery-saving preset in the app that reduces bass response) and you might squeeze past 30 hours.

Quick charging delivers three hours of playback from a 10-minute charge, though a full 0-100% charge takes roughly four hours. You can use the ULT Field 7 whilst it’s charging via mains power, handy for extended garden parties where you’ve access to an outlet.

The USB-A port on the rear panel functions as a power bank for charging phones or tablets. Maximum output is a paltry 7.5 watts — enough for slow emergency charging, but hardly impressive in an era where 20W+ charging is standard. It’s better than nothing but feels mean-spirited on a £349 speaker.

One niggle: there’s no battery percentage display on the speaker itself, just a vague LED indicator. You’ll need to check the app for the precise remaining charge, which is unnecessarily fiddly.

Battery Care mode limits charging to 90% to extend the battery’s lifespan over years of use. It’s a thoughtful inclusion that more manufacturers should adopt, even if it means sacrificing a couple of hours of runtime.

Sound Quality

• Powerful bass performance
• Warm, cohesive tonality
• Excellent outdoor projection
• Detail takes a backseat

Make no mistake: the Sony ULT Field 7 is built for bass, and it delivers in spades. Those square 114mm x 114mm X-Balanced woofers shift serious air, aided by substantial passive radiators at each end. The result is low-frequency performance that can genuinely rattle your ribcage.

In standard mode (both ULT settings off), the ULT Field 7 presents a warm, slightly bass-forward signature that’s actually quite pleasant. Vocals come through with clarity and surprising presence given the speaker’s party-centric tuning. There’s decent separation between instruments, and the high-efficiency tweeters provide adequate sparkle in the upper frequencies.

Streaming Charli XCX’s Von Dutch via Apple Music, the speaker handles the energetic bassline without muddying the crisp vocals. There’s genuine punch to the kick drums, and the synth layers remain distinct rather than collapsing into mush. It’s hardly audiophile territory, but it’s considerably more refined than you’d expect from a bass-monster party speaker.

Engage ULT1, and the character transforms. Low frequencies gain substantial weight and depth, extending into genuinely deep territory. Kendrick Lamar’s bass-heavy production on GNX comes alive, delivering the sort of visceral impact that makes your chest resonate. It’s intoxicating stuff for bass enthusiasts, though purists will bemoan the elevated low-end response.

The catch? ULT1 can overwhelm more balanced recordings. Orchestral music becomes bass-heavy to the point of absurdity, and acoustic guitar takes on an unnatural warmth. This isn’t a criticism, per se; after all, the ULT Field 7 knows its audience, and that audience is looking to ‘get lit’ or simply ‘flex’, not pore over the finer details of Tchaikovsky’s 1812 Overture.

ULT2 is the outdoor party mode, emphasising mid-bass for increased perceived loudness and projection. It’s less refined than ULT1, trading deep extension for punchy immediacy. Played at volume in an open space, it’s devastatingly effective. You can feel the music from significant distances. Indoors, it’s bordering on obnoxious unless you’ve got space to spread out.

Testing across genres, the ULT Field 7 excels with modern production. Hip-hop, dance, pop, and rock all benefit from the speaker’s muscular low-end and energetic presentation. Jazz and classical fare less well, though again, you’re probably not buying this speaker for late-night Miles Davis sessions.

Maximum volume is properly loud enough to entertain a garden party or small outdoor gathering without strain. There’s some compression as you approach the limits, but the speaker remains composed until you’re well into antisocial territory. Your neighbours will let you know when you’ve gone too far.

Detail isn’t the ULT Field 7’s strong suit. Subtle touches, delicate instrumental textures, and nuanced vocals take a back seat to sheer impact. It’s the trade-off you make for a speaker tuned to move air rather than reveal micro-details.

Stereo imaging is respectable for a tubular design. The two tweeters and woofers are spaced reasonably far apart, creating a decent sense of width. It’s not proper audiophile-grade, but you can discern left-right positioning reasonably well.

One genuine strength: the ULT Field 7 maintains coherence and clarity even at high volumes outdoors. Some portable speakers fall apart when asked to fill open spaces, but Sony’s speaker projects admirably. Bass remains tight, vocals stay intelligible, and the overall presentation hangs together impressively.

App

• Sony Sound Connect
• Modern, responsive interface
• Comprehensive features

The ULT Field 7 has been compatible with Sony’s Sound Connect app since April 2025, replacing the older Music Center app. Sound Connect offers a significantly improved experience with a modern interface and more intuitive navigation.

Comprehensive controls include a customisable 7-band EQ, lighting controls with multiple patterns, Party Connect management, Sound Field Optimization, and various sound presets, including the ULT modes and Stamina. There are even DJ-focused tools, including an isolator and flanger effects.

Functionally, it’s well-designed and responsive. The interface is clean and accessible, making adjustments straightforward. Setup is intuitive, and the app stays connected reliably in the background.

You rarely need the app, however. Physical controls on the speaker cover most essential functions, including the ULT modes, volume, playback, and lighting on/off. You’ll probably use the app for initial setup and occasional EQ tweaking, then rely on the physical buttons.

Note: To use Sound Connect with the ULT Field 7, you may need to update the speaker’s firmware first using the Music Center app.

Should you buy it?