Soundcore Boom 3i Review: A Saltwater-Ready Speaker That Floats Upright

The Soundcore Boom 3i is the portable speaker to buy if it's going on a kayak, a paddleboard, a boat or a sandy beach. It is IP68, built for saltwater, and floats with its drivers pointing up so the music stays audible. Skip it if you mostly listen on land and care most about sound quality or party linking: it plays in mono, lacks deep bass, and only pairs with one other Boom 3i.

Soundcore rates the Boom 3i at 50 W with 16 hours of playback, Bluetooth 5.3 and a 1-meter drop rating. RTINGS measured 15 hours with the lights off and rates it good for outdoor use, and SoundGuys calls it the one to get for lake days, paddleboarding trips and river floats.

ArmorSound has not tested the Boom 3i. This review combines Soundcore's specifications with independent reviews from RTINGS, SoundGuys and Headphonecheck.

Where to buy

Our verdict

Soundcore Boom 3i

Best for: Kayaking, boating and beach days

Output

50 W

Battery

16 hr rated, 15 hr in RTINGS testing

Water rating

IP68, saltwater-resistant, floats upright

Weight

780 g (1.7 lb)

Bluetooth

5.3, stereo pair with a second unit

• Floats with drivers facing up
• IP68 with a saltwater-resistance claim and 1 m drop rating
• About 15 hours of battery in RTINGS testing
• Buzz Clean, emergency alarm and 9-band EQ in the app

• Mono playback and limited deep bass
• No party mode, aux input or speakerphone
• Small strap clips can slide off and get lost

Watch for: Out of the box SoundGuys found the default sound dark, so plan to adjust the 9-band EQ in the Soundcore app.

Check price on soundcore's Amazon store →

What are the Soundcore Boom 3i key specs?

Can the Boom 3i handle salt water and float upright?

This is why the Boom 3i exists. Plenty of speakers are IP67 or IP68, but Soundcore also claims 5x saltwater resistance against sea spray and corrosion. RTINGS notes that the IP68 rating itself isn't unusual, and that the saltwater and 1-meter drop promises take it further.

The floating design is the clever part. RTINGS confirms the speaker rotates itself while floating so the drivers face upward. Speakers that float on their side can sound muffled; RTINGS makes exactly that point about the Ultimate Ears BOOM 4.

SoundGuys describes a tough plastic shell with chunky rubber bumpers that also protect the light panels on the passive radiators. Headphonecheck's test says it can be submerged to 1.5 meters for 30 minutes and puts the USB-C port behind a thick rubber cap.

Saltwater resistance doesn't mean zero maintenance. Rinse it with fresh water after the ocean and let it dry with the cap closed before charging. Our guide to speaker IP ratings explains what IP68 does and does not cover.

How does the Boom 3i sound, according to reviews?

Expect clear, mostly balanced sound rather than deep bass. RTINGS describes a mostly balanced profile that suits most audio but lacks deep bass. It also downmixes stereo to mono unless you pair a second unit, and SoundGuys confirms it is a mono speaker.

SoundGuys found the default Soundcore Signature preset dark, lacking treble clarity, and fixed it with the 9-band custom EQ by lifting some low frequencies and the 5 kHz and 9 kHz sliders. The reviewer notes more bass is available through EQ, at the cost of battery life.

Headphonecheck is the toughest critic. Its reviewer found it solid up to about half volume with BassUp on, but heard boxy, dull mids and highs that start to hiss as volume rises, and concluded it's not for sound purists or big parties.

The headline 50 W figure is best read as a peak number. Notebookcheck's launch report points out it is most likely a peak output figure. RTINGS says the JBL Charge 6 gets louder and delivers more bass by default.

How long does the Boom 3i battery last, and how does it charge?

Soundcore rates 16 hours. Headphonecheck says that figure assumes the light effects are off and volume stays below 50%. RTINGS measured 15 hours with the lightshow off and calls it amazing for the size.

Charging is over USB-C. SoundGuys confirms you can play music while it charges, but the Boom 3i can't charge your phone; Soundcore's own comparison chart marks charge-out as absent. Soundcore's US product page doesn't list a charge time.

What app and outdoor features does the Boom 3i have?

The Soundcore app is where the Boom 3i earns its keep. SoundGuys and Headphonecheck describe a 9-band custom EQ plus presets, a long list of light modes and a sleep timer.

• Buzz Clean. Plays a low-frequency sweep that shakes sand and dirt out of the drivers and radiators. RTINGS and SoundGuys both single it out as unusual.
• Emergency Alarm. Hold the BassUp button for 5 seconds to sound a 96 dB alarm that Soundcore says is audible at up to 100 meters.
• Voice Amplifier. Headphonecheck explains that it plays messages you record on your phone through the speaker, once or on a loop. It is not a live microphone.
• Lights. RGB effects that can follow the beat. RTINGS' battery figure assumes they are off.

How does the Boom 3i connect and pair with other speakers?

The Boom 3i uses Bluetooth 5.3, and RTINGS calls its range superb, so you can leave your phone on the boat or poolside. Headphonecheck says multipoint is supported and that Soundcore doesn't disclose which codecs it uses.

Multi-speaker options are limited. Soundcore lists TWS, so two Boom 3i speakers can split left and right channels, but RTINGS notes there is no party mode for linking a group. There is no aux input, per SoundGuys, and RTINGS lists no speakerphone, so it can't take calls.

One small annoyance: RTINGS and SoundGuys both warn that the plastic strap clips are small and can slide off the strap, which matters most when you're over deep water.

What do Boom 3i owners report?

Spec sheets and lab reviews only go so far. Here is what owners say after living with it, drawn from Reddit discussions collected by RedditRecs.

• Compact with a great sound. An owner of several Soundcore and Bose speakers describes the Boom 3i as small and compact with a great sound. (r/Bluetooth_Speakers)
• An underrated pick. A commenter recommending a Charge 6 adds that the Boom 3i is really good and does not get mentioned enough. (r/Bluetooth_Speakers)
• Deep electronic bass is its limit. An owner praises the waterproofing but says the bass gets dirty on certain deep techno tracks. (r/Bluetooth_Speakers)

Owners like its size and toughness. Heavy bass music is where it runs out of room.

Who should buy the Boom 3i, and who should skip it?

Buy the Boom 3i if:

• You kayak, paddleboard, fish or boat, or spend time on salt water.
• You want a speaker that keeps playing clearly if it goes overboard.
• You like features such as Buzz Clean and an emergency alarm.
• You want a full day of battery from a 1.7-pound speaker.

Skip it if:

• You want deep bass or stereo sound from a single speaker.
• You want to link a group of speakers for a party.
• You need an aux input, speakerphone or a speaker that can charge your phone.

Which speakers are alternatives to the Boom 3i?

Soundcore Boom 2. SoundGuys suggests it if you need more output: 80 W, stereo playback and party lights. Soundcore's chart lists 24 hours, IPX7, floating, Auracast and charge-out, but it's more than twice the weight and lacks dust protection. See our Soundcore Boom 2 review.

JBL Flip 7. RTINGS calls the two very similar in price and sound. The Flip 7 has IP68, a 1-meter drop rating and Auracast for linking JBL speakers, but it doesn't float like the Boom 3i, and RTINGS picks the Boom 3i for its longer battery life. Read our JBL Flip 7 review.

JBL Charge 6. RTINGS says the larger Charge 6 gets louder with more bass, and that both float, but only the Boom 3i keeps its drivers facing up. Pick the JBL for bigger spaces or Auracast parties; our JBL Charge 6 review covers it.

Ultimate Ears Wonderboom 4. Smaller and lighter, with 360-degree sound. Ultimate Ears rates it IP67 and says it floats, though it has no app or saltwater claim. Our Wonderboom 4 review explains the trade-offs.

For dry-land listening on a budget, the Tribit XSound Plus 2 offers longer rated battery life and an aux input. The Skullcandy Barrel Mini and Monster Shock Plus are louder-looking budget boomboxes, but neither has independent test data and neither floats. Klipsch The Detroit is a waterproof portable, and Klipsch The Three Plus tabletop stereo takes a turntable.

Frequently asked questions

Sources

• Soundcore: Boom 3i product page, specs and comparison chart
• RTINGS: Anker Soundcore Boom 3i review (verdict, pros and cons, comparisons)
• SoundGuys: Soundcore Boom 3i review
• Headphonecheck: Soundcore Boom 3i test
• Notebookcheck: Soundcore Boom 3i launch report (May 2025)
• JBL: Flip 7 product page and specifications
• Ultimate Ears: Wonderboom 4 product page and specifications