Remember the days when people carried massive boomboxes on their shoulders, blasting disco so the whole neighborhood could hear? In many ways, not much has changed. People still carry their music with them everywhere, they just do it now with compact Bluetooth speakers.
The global portable speaker market was valued at around $12.9 billion in 2023 and is expected to nearly double to approximately $27.9 billion by 2030, with a compound annual growth rate (CAGR) of about 11.6%. Those numbers haven’t gone unnoticed by the major players—Sony among them.
Sony Holds Its Ground
Sony entered the Bluetooth speaker space over a decade ago, and it hasn’t looked back. Last year, the company introduced its ULT Power Sound lineup, featuring models like the ULT Tower 10 and 7, along with headphones equipped with a dedicated ULT button designed to boost bass output.
The idea behind the ULT series is simple: deep, powerful bass, something Sony believes resonates strongly with younger audiences. The dedicated ULT button instantly enhances bass levels, allowing users to tailor the listening experience on the fly.
ULT Power Sound Expands
In April, Sony expanded the lineup with additional models: ULT Field 3, 5, and 9, under the slogan “Massive Bass, Ultimate Vibe,” aiming to deliver a front-row concert experience.
The series includes large tower-style speakers (ULT Tower 9), available in both battery-powered and wired versions, which are less portable due to their size. The Field 3 and Field 5, however, are designed for mobility, each equipped with a carrying strap. The Field 3 review can be found here.
ULT Field 5: The Sweet Spot
From my perspective, the ULT Field 5 is the standout model in the lineup. It strikes a compelling balance: large enough to deliver serious power, yet still portable enough for outdoor use: camping trips, beach days, or backyard parties, thanks to its comfortable shoulder strap.
Design
The Field 5 features a rugged, compact design with a prominent shoulder strap. It’s wrapped in a durable exterior and accented with colorful LED lighting that pulses in sync with the music. A sleek Sony logo adds a modern touch.
The speaker can be positioned either vertically or horizontally, depending on your setup. With an IP67 rating for water and dust resistance, it’s built to handle environments like the beach or pool without concern.
Around the back, all ports are protected by a sealed cover to keep out sand and moisture. Connectivity includes a 3.5mm input, USB-C charging, a battery protection option that limits charging to 90%, and the ability to disable lighting to conserve power.
Technical Specifications
The ULT Field 5 supports Bluetooth 5.3 and includes Auracast compatibility, allowing connection with up to 100 speakers simultaneously, what Sony calls Party Connect.
Inside the speaker you’ll find two 60mm woofers, two 40mm midrange drivers two tweeters and dual passive radiators.
The built-in battery delivers up to 25 hours of playback, and a quick 10-minute charge provides around two hours of listening time. Output is rated at 30W RMS, and supported codecs include SBC, AAC, and LDAC.
Sound Connect App
Once I opened the Sound Connect app, it apeared that Sony has clearly invested effort into it to maximize the Field 5 experience. One surprising limitation is that pairing the speaker requires using the app: the speaker won’t connect directly through the standard Bluetooth menu, which may feel unintuitive at first.
Once connected, the app prompts a firmware update, which takes a few minutes. After that, it unlocks the full audiovisual experience Sony is aiming for. The app keeps you engaged throughout use to switch between sound modes, adjust lighting colors and patterns, control bass intensity and customize EQ with a 10-band equalizer.
Sony also includes a battery care feature that limits charging to 90% to extend battery lifespan, which I find as a thoughtful addition.
User Experience
From the moment I powered on the ULT Field 5, it became clear that its compact appearance is misleading, because this speaker packs serious power. The bass is deep, punchy, and physically present. It fills the space and adds a sense of energy to any track. Mid frequencies do take a slight step back, but not enough to detract significantly from the overall balance.
Controls are located on the back of the unit. Buttoms include ULT, volume, power, and Bluetooth, and they are easy to access and use. During testing, I found that ULT1 mode offers the best balance. It enhances bass while keeping the rest of the soundstage open and clear.
For example:
“Back in Black” by AC/DC sounded dynamic and well-defined, with crisp harmonics and a lively feel. The “Blinding Lights” by The Weeknd delivered a more balanced and controlled output in ULT1 mode. And “Titanium” by David Guetta showcased the speaker’s ability to energize a space. It’s really hard not to move when it’s playing
ULT2, on the other hand, is best suited for outdoor environments where you want maximum bass impact, like open-air parties. Each press of the ULT button triggers a distinct sound cue, reinforcing the sense of stepping up the intensity.
To complete the experience, the speaker’s LED lighting syncs with the music, creating a visual layer that enhances the atmosphere. It’s not just about sound, but about presence. That said, lighting does impact battery life. Fortunately, you can enable a power-saving mode that disables lighting and reduces ULT intensity. Battery status can be monitored through the app or via LED indicators on the speaker itself.
Final Thoughts
If you’re looking for a Bluetooth speaker that can handle outdoor settings, such as picnics, beach days, pool parties, while delivering powerful, room-filling bass, the ULT Field 5 hits the mark. It’s fun, energetic, and fully lives up to Sony’s “Massive Bass, Ultimate Vibe” promise. Activating ULT mode genuinely creates a front-row experience.
This speaker clearly targets younger audiences and anyone looking to bring a party wherever they go, but it also appeals to travelers who want portability without sacrificing performance. It’s not the lightest speaker out there, but the shoulder strap makes it easy to carry, and the weight quickly becomes a non-issue.
Bottom line: if you’re after big sound, bold bass, colorful lighting, and durability for outdoor use, the Sony ULT Field 5 delivers a surprisingly powerful and enjoyable package.
Price (approx.): $320