Sony ULT Field 7

How does it perform?

The ULT Field 7 strikes an impressive balance between portable speaker and party box, excelling where it matters most. Expert measurements confirm crystal-clear vocals and instruments at moderate volumes, while customer reviews consistently praise its room-filling volume and bass. The 30-hour battery claim holds up at reasonable listening levels, though enabling ULT modes and LED lighting cuts that down to 10-12 hours in real-world party conditions. Its exceptionally low latency—sub-150ms for both iOS and Android—eliminates audio-video sync issues entirely, making it ideal for streaming movies or gaming. The IP67 rating and rust-resistant construction handle genuine abuse at beaches and pools without breaking stride.

What’s it do best?

The ULT Field 7 excels as a karaoke-ready party speaker that actually sounds good. Those built-in 1/4-inch mic and guitar inputs aren’t just gimmicks—they transform this into a legitimate PA system for backyard weddings or karaoke nights. The IP67 rating survives real outdoor punishment, from poolside splashes to dusty camping trips. Bass performance stands out, with genuine 20Hz extension that you feel in your chest, not just hear. And that sub-150ms latency means you can use it for video production or streaming without the audio lagging behind the picture—rare for a Bluetooth speaker at any price.

Audio performance Quality

Frequency Response Range

Wide frequency coverage determines how completely the speaker reproduces music across the audible spectrum.

• Expert Measured: 20Hz bass extension confirmed with reduced volume
• Manufacturer Claimed: 20Hz to 20kHz

The Field 7 achieves genuine low-frequency extension down to 20Hz, though like most portable speakers, output drops significantly at the extremes.

Total Harmonic Distortion (THD)

Lower distortion preserves audio fidelity, especially important for vocal clarity and instrument definition.

• ULT 1 Mode: 4.1% THD measured
• ULT 2 Mode: 3.3%

THD measured Despite powerful bass enhancement, THD remains within acceptable ranges, contributing to the speaker’s praised vocal clarity.

Sensitivity/Maximum SPL

High sensitivity enables louder output from available power, crucial for party and outdoor applications.

• MDAQS Timbre (MOS-T) score (ULT 1): 4.10
• MDAQS Timbre (MOS-T) score (ULT 2): 3.80
• Maximum Peak Intensity: 104.3 dBc at 1.5m

Multiple reviews confirm the Field 7 achieves substantial volume levels suitable for large gatherings, with objective measurements supporting its high output capability. However, bass-forward tuning can obscure midrange detail at party volumes, and some reviewers note strings sound “shrieky” when pushed hard.

Connectivity Performance

Audio Latency

Low latency ensures proper audio-video synchronization for streaming content.

• iOS/Android: Sub-150ms measured

• Expert Testing: “Exceptional” latency performance noted

The Field 7 excels in video applications, with reviewers specifically praising its sync performance, making it ideal for multimedia consumption.

Codec Support Quality

Advanced codec support improves wireless audio fidelity and connection stability.

• Supported Codecs: SBC, AAC, LDAC

• LDAC Bitrate: Up to 990kbps transmission

LDAC support enables high-resolution wireless transmission for compatible devices, contributing to the speaker’s audio fidelity.

Power Management and Battery Performance

Battery Capacity

Larger capacity enables extended playback duration for portable applications.

• Battery Voltage: 7.22V
• Battery Capacity: 5200mAh
• Estimated Capacity: 37Wh (based on 5200mAh at 7.22V)

While Sony doesn’t publish exact capacity, real-world endurance impresses users at moderate volumes, with objective data supporting its substantial capacity.

Playback Duration

Extended runtime reduces charging frequency during events and travel.

• Manufacturer Claim: Up to 30 hours
• Real-World Testing (LED/ULT disabled at 25% volume): 30 hours
• Real-World Testing (ULT on, volume 36%, lights off): 25 hours
• Real-World Testing (ULT on, volume 36%, lights on): 10 hours
• Real-World Testing (50% volume with lights on in ULT mode): 12 hours

Battery life consistently meets manufacturer claims at moderate volumes with features disabled, but drops dramatically to 10-12 hours when you actually use it as a party speaker with ULT bass modes and LED lighting enabled.

Charging Time

• Recharge Time (0-100%): 3.83 hours (average)

Full recharge time is approximately under 4 hours, which is efficient for its battery capacity. However, the speaker charges via AC power only using a figure-eight plug—no USB-C charging option, which feels dated for a $500 speaker in 2024.

Fast Charging Capability

Quick charging reduces downtime between uses.

• Quick Charge: 10 minutes for an average of 152 minutes playback

Fast charging capability provides practical convenience for busy users, offering significant playback from short charges.

Build Quality

Water Resistance Rating

IP67 certification ensures protection against dust and temporary immersion.

• Rating: IP67 (dust-tight, 1-meter submersion for 30 minutes)
• Additional Protection: Rust-resistant coating

The comprehensive environmental protection exceeds typical Bluetooth speaker standards, making it highly suitable for outdoor use.

Enclosure Material Quality

Construction materials determine long-term durability and premium feel.

• Materials: Mesh fabric exterior with plastic housing
• User Feedback: “Rugged feel” and “built like a tank”

Multiple reviewers confirm solid construction quality, ensuring durability for demanding environments.

Soundstage

Directivity Pattern

This covers how well a speaker does at projecting audio out from its speakers to create the feeling of instruments and sounds being in a “place”, instead of just being a noise that’s coming out of a device in front of you.

• Reviewers note “sub-par directivity” and “music is projected in only one direction (towards Sony logo)” in some orientations, though its vertical/horizontal placement adds versatility.

While its directivity could be improved, the ability to position it vertically helps optimize bass.

Setup and Usability

Multi-device Management

The ULT Field 7 supports simultaneous connection to two devices via Bluetooth 5.3, allowing for smooth switching between sources like a tablet and a phone. This feature enhances user convenience for multi-device setups.

Software Integration

The speaker uses the Sony Sound Connect app (an update from the previous Music Center app), offering features like a 7-band EQ, ULT mode controls, and lighting customization. However, the app receives significant criticism for being “poorly designed,” “laggy,” “unintuitive,” and experiencing “connection issues,” with some reviewers describing it as “lackluster” and “appalling.” The app’s poor performance undermines what should be straightforward control over the speaker’s extensive feature set.

Control Interface Design

The speaker features dedicated control buttons for power, pairing, track, volume, and ULT modes, with the ULT button being RGB backlit. However, some users find the volume buttons increment microscopically, requiring many presses for noticeable change, which becomes genuinely annoying during use. The USB-A output for charging devices also maxes out at a piddly 7.5W, which is weak for a $500 speaker.