I love a good portable speaker. Whether I’m working in the backyard, hanging at the lake, or just vibing with some tunes while cooking, a good Bluetooth speaker is always within reach. So when I saw Sony’s new ULT Field speakers going on early Prime Day sale, I knew I had to share the deal with you.

Sony launched the ULT Field series as part of its new ULT Power Sound lineup—a family of audio products built for people who like their music loud, bass-heavy, and portable. Think rugged exteriors, water and dust resistance, long battery life, and most importantly, serious audio firepower.

If you're even remotely in the market for a portable speaker right now, these early deals are worth a closer look:

• Sony ULT Field 1 – Originally $129.99, now $88.00
• Sony ULT Field 3 – Originally $199.99, now $148.00
• Sony ULT Field 5 – Originally $329.99, now $248.00

And these aren’t just your average “meh” speakers with a flashy name. Let me walk you through each one so you can decide which ULT Field fits your life best.

Sony ULT Field 1 – Small Speaker, Big Personality

The ULT Field 1 is the baby of the bunch, but don’t underestimate it. This thing can go from your bedroom desk to a sandy beach without skipping a beat. It’s IP67 rated, meaning it can survive water, dust, and the occasional drop with no complaints.

It features a two-way speaker system—a woofer and a separate tweeter—which helps give it a cleaner, more detailed sound than most speakers its size. Sony also gave it a passive radiator to help boost the bass. Add the ULT button, which brings in a stronger low-end response, and suddenly this little guy can actually thump.

Battery life is around 12 to 14.5 hours, depending on volume and bass boost. I love how it feels like a mini boombox with the included carry strap—perfect for hikes, bike rides, or casual trips.

Why you should grab it: For $88 at Amazon, it’s honestly one of the most well-rounded portable Bluetooth speakers under $100 right now. It competes with JBL’s Flip series and offers even richer sound in a more stylish package.

Sony ULT Field 3 – The Goldilocks Option

Here’s where things get really interesting. The ULT Field 3 is the “just right” option—bigger than the Field 1, but still compact enough to throw in a bag or carry by the strap. It has a mono setup with a full-range woofer and tweeter, flanked by passive radiators, and it leans slightly toward bass-heavy tuning even before you hit the ULT bass boost.

Sony claims up to 24 hours of battery life, and in real-world use, that number holds up well unless you max the volume or use bass boost constantly. Plus, it supports voice assistants, USB-C charging, and stereo pairing if you buy two of them.

Sound-wise, it’s warm, full-bodied, and surprisingly refined for a $148 speaker. I’d say it’s the best value of the three for people who want a high-quality sound without needing full stereo output.

Why you should grab it: It’s powerful enough to fill a room or backyard, durable enough for outdoor adventures, and portable enough to take anywhere. It’s the do-everything speaker.

Sony ULT Field 5 – Built for Bass and Backyard Parties

Now, this is the big one. The ULT Field 5 is what you bring to a party, a camping trip, or anywhere you want to seriously turn up. It has two woofers, two tweeters, and a stereo layout, making it a rare portable speaker that actually delivers true stereo separation. And with two ULT modes for different bass levels, you can go from deep and punchy to earthquake-adjacent depending on your mood.

You also get multi-colored LED lighting, full 10-band EQ support in the Sony Music Center app, Party Connect for linking with other compatible Sony speakers, and USB-C fast charging. It even works as a speakerphone if you’re brave enough to take a work call through it (don’t).

Battery life can hit 25 hours, though if you turn on all the bells and whistles, expect less.

Why you should grab it: At $248, it’s basically a compact party-in-a-box. The stereo sound, rich bass, and long battery life make it ideal for everything from weekend barbecues to small outdoor events. It’s the ultimate portable setup.

Which One Should You Get?

Here’s my honest breakdown: 

• If you want something ultra-portable, easy to pack, but still sounds great, get ULT Field 1.
• If you want the best all-around sound, battery life, and price balance, get ULT Field 3.
• If you want real stereo, max bass, LED lighting, and don’t mind the size, get ULT Field 5.

Personally, I’m tempted to grab both the Field 1 and Field 3. I love having the smaller one for travel and solo use, and the Field 3 feels like the daily driver. But if you’re the type to host movie nights, tailgates, or full-blown grill-outs? Just get the Field 5—you’ll thank yourself later.

Sony rarely goes this deep with discounts on new gear, and these early Prime Day deals are especially sweet since the ULT Field line just launched earlier this year. Whether you’re upgrading from an older speaker, buying your first one, or looking for a gift, this is a great time to jump in.

The bass is punchy, the sound is clean, the design is rugged, and all three models just work. No weird setup, no gimmicks—just great portable audio for every kind of listener.

Seriously, don’t sleep on these deals. If you're even remotely thinking about a new Bluetooth speaker this summer, one of these should be on your shortlist.