The JBL PartyBox 300 Review: Your Party’s Ultimate Music Machine

JBL PartyBox 300

I’ve reviewed plenty of oversized connected speakers, but the JBL PartyBox 300 takes that concept to the next level. It’s cordless when you need it to be, it has microphone and guitar inputs, it can put on a light show, it’s loud enough to fill your backyard, and man — it sounds amazing!

Let’s get one thing out of the way before we dig in: the JBL PartyBox 300 is portable, but it is not easily lifted. Measuring approximately 27.25″ tall by 13″ wide (including the slightly protruding feet on each side) by 12.25″ deep and weighing 25 pounds, this speaker is a beast! I thought that the JBL Boombox was impressive when used outside, but this thing puts it to shame in large, open spaces!

JBL PartyBox 300 Features:

  • JBL Signature Sound Light shows
  • Portable with a rechargeable battery
  • Mic and guitar inputs
  • Wireless Bluetooth Streaming
  • Transducer: two 6.5″ woofers, three 2.25″ tweeters
  • Frequency Response: 45Hz–20kHz
  • Bass Boost
  • USB playback
  • TWS and RCA
  • Power Inputs: 100–240V AC and 12V
  • Output Terminals: RCA L/R TWS (True Wireless Stereo) connecting up to 2 party speakers using Bluetooth technology
  • Battery Type: Lithium-ion 74.88Wh (equivalent to 7.2V 10400mAh)
  • 5 hours to charge with 18 hours of battery play time
  • USB recharging for external devices

Inside the box, you’ll find the JBL Party Speaker, and AC power cord, a 12V DC cable, a quick-start guide, a warranty card, and a safety sheet.

The matte black exterior is broken up by the red JBL logo on the front and the orange handles on the top and bottom. Moving the JBL PartyBox 300 can be done by one strong person, but the speaker is so large it’s really a two-person job; that should give you an idea of how big it is.

JBL PartyBox 300

There are four orange feet on the right and left sides

On the back, there is a 6″ port for the bass reflex system. This type of system allows the speaker to put out even more impressive and loud bass sound without having to use even larger woofers. This system works, let me tell you.

JBL PartyBox 300

Also located on the back are the following ports and controls: a DC port for powering from your car, the AC power port, a 5V 2.1A USB port for powering your phone while it pushes music, an Aux port (for your non-Bluetooth enabled music players), input and output RCA jacks, a L/R channel button for when you are connecting two PartyBox 300s together for even more massive sound, a microphone jack with its own volume button, and a guitar jack with its own volume button. In other words, the PartyBox 300 can handle just about any scenario you might try to throw at it.

JBL PartyBox 300

On the top of the JBL PartyBox 300, there is a volume up button, a Play/Pause/Resume button (pressing it twice will advance it to the next song), a volume down button, a bass boost button (off or on), a Power button, a Bluetooth pairing button, and a dedicated light show button (modes include meter, pulse, party, and off). There is no connected app; all of the controls that you’ll need are right there on the box.

JBL PartyBox 300

If you like the JBL Pulse, and how it gives you a synchronized light show while your music is playing, you’ll love that there are three pre-programmed light shows that you can engage while your music is playing. If you already have a light show going elsewhere, or if you prefer listening to your music without all of the bells and whistles, you can also opt to turn the LED light show completely off.

I was afraid that I would find the lights cheesy, but they are actually quite fun — especially at night. Watching them change colors and dance in synchronicity to the songs’ beats adds to the experience. The overall effect is just begging for a dusk to dawn party, although the light show is bright enough to catch attention in broad daylight, too. If you’re using the PartyBox indoors, and you don’t want to feel like you’re at a rave, you can simply turn them off.

You can even plug a USB stick into the USB Type-A port on the back if you’ve loaded your favorite mix and don’t want to stream from a device.

To use a USB stick:

  1. Get an empty USB stick with speed of 2.0.
  2. Make sure it is formatted with FAT16 or FAT32.
  3. Your Music files can only be: MP3

Powering a speaker this large might seem like a pain, depending upon the location you’re utilizing, but that’s just another way the JBL PartyBox 300 gives you options: You can plug it into a wall, you can plug it into your car, or you can charge it ahead of time and let its 10,400mAh battery do its thing for up to 18 hours of playtime. Even though it seems like this should be obvious, you should be aware that if you play the PartyBox at full volume and with the lights on, battery life will be affected

The only caveat is that the PartyBox doesn’t have any water-resistance, so you’ll want to set it away from your pool’s splash zone, and if it is kelp outside, you should keep it well under cover.

If you’re all in, and you buy two PartyBox 300s, you can take advantage of True Wireless Stereo; by connecting two PartyBoxes together via Bluetooth, you can set one speaker as a right channel and the other as a left channel — giving you true stereo sound wirelessly. If one PartyBox is impressive, imagine how two would look on either side of your DJ’s booth, with you in the middle on your electric guitar, or on the edge of your dance area.

Inside the PartyBox 300, there are two 6.5″ woofers and three 2.25″ tweeters; the sound produced is massive. The PartyBox 300 would work equally well in your home, on your back deck, in your back yard, or in any space with a dance floor. It can be stood upright, or you can lay it on its side; the JBL PartyBox will automatically adjust itself to optimize sound for either scenario.

JBL PartyBox 300

This pic is for my friend Bobby, who wanted to see the PartyBox next to a Dr. Pepper can. 😉

Getting set up is simple: It takes a couple of hours to fully charge before your first use, but you can also use it while it’s plugged in. The PartyBox can be paired with up to 8 different devices with distances of up to 30 feet by pressing the Bluetooth button on the top for a second or two until you hear a tone; if you add a 9th device, it will automatically drop the first device that was added.

The JBL PartyBox 300 is versatile; you can hook the JBL PartyBox up to your home audio system or television with the RCA inputs. If you want to accompany the music playing with vocals or guitar, you can plug your mic or guitar into the back and adjust the volume for that device with the accompanying knob above its proper jack on the back — and you can use both accessories at the same time.

The sound the JBL PartyBox 300 puts out is phenomenal! The JBL tuning never disappoints, and if you’re a fan then you will absolutely love what this speaker produces. Highs are crisp, clean, and clear as a bell (MØ’s Blur is sumptuous and never tinny), the midrange isn’t muddy at all (it handles Radiohead’s Burn the Witch perfectly), and the bass can either be substantial or booming (Jay Z’s Can I Get A .. thumps hard without ever bottoming out)  — which is perfect in large open areas.

Be advised that if you are listening to the speaker in all but the largest rooms, you will likely never need to turn it up more than halfway. At higher volumes (when inside), the bass will literally rattle windows and things sitting on your floor; outside, that’s obviously not an issue.

Whether you are playing rap, folk, classical, punk, R&B, country, or thrash — the JBL PartyBox 300 has you covered! We are now in full-season for backyard and pool parties, and the JBL PartyBox is here to take your festivities to the next level.

The JBL PartyBox 300 retails for $449.95, and it is available directly from the manufacturer and from other retailers including Amazon. There is also a JBL PartyBox 200 available that has all of these features minus the internal battery; it retails for $379.59 on Amazon [affilliate links].

Source: Manufacturer supplied review sample

What I Like: A huge yet still portable battery-powered speaker; Includes a DC cable for powering from your car; Can be paired with up to 8 different Bluetooth streaming devices; Extraordinarily loud — can fill your backyard or other outdoor spaces; Can be used inside; Every kind of connection you might need — RCA, mic, and guitar; You can play MP3s from a pre-programmed USB stick; Aux-in for your iPod or other non-Bluetooth streaming devices; You can charge your phone or tablet from the USB port on the back; 10,400mAh battery lasts up to 18 hours

What Needs Improvement: No water resistance whatsoever, so if you are using this outdoors and there is a chance of rain or splashing, be sure to keep it somewhere safe

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About the Author

Judie Lipsett Stanford
Judie is the co-owner and Editor-in-Chief of Gear Diary, which she founded in September 2006. She started in 1999 writing software reviews at the now-defunct smaller.com; from mid-2000 through 2006, she wrote hardware reviews for and co-edited at The Gadgeteer. A recipient of the Sigma Kappa Colby Award for Technology, Judie is best known for her device-agnostic approach, deep-dive reviews, and enjoyment of exploring the latest tech, gadgets, and gear.