In-ear monitors (IEMs) are rapidly gaining popularity amongst DJs and they’re something I’ve wanted to have a good look at for a while.

In-ear systems offer different benefits over traditional on-ear or over-ear headphones. Some factors to consider when choosing in-ear monitors include:

Sound isolation: It’s well recorded that IEMs provide better sound isolation compared to regular headphones. Using them helps block out external noise and allows you to focus on your mix without distractions.

Comfort: Well-fitting IEMs can be very comfortable for extended use, as they don't put pressure on the head or ears like traditional on-ear headphones might. The included earpieces will help make that match for your ear whilst upgrading the cable to a custom moulded unit will be top of the range.

Sound quality: Look for IEMs with good frequency response, clear mids, defined highs, and impactful bass. Sound quality is paramount for mixing.

Detachable cables: IEMs with detachable cables are practical, as they allow for easy replacement if a cable gets damaged. (If needed, Xvive’s U4T9 system allows you to replace each individual part, available to order from your local retailer.)

Low latency: Minimal latency is important for DJs, as it ensures that what we're hearing is in sync with our actions.

Like most DJs, I work in intensely loud environments and until now I’ve relied on a combination of moulded ear protection (ear plugs) and headphones. However, I find I need my headphones even louder than normal in order to hear over my -18db plugs, which then makes me wonder if I’m defeating the whole purpose of wearing protection at all!

So when Paul from JHS contacted me about the Xvive U4T9 – a new system which they are the UK distributor for – I jumped at the chance to review it for the magazine.

In the box

The U4T9 is an in-ear monitor bundle consisting of a transmitter, a receiver (U4), and a set of T9 in-ear monitors.

On delivery I found a comprehensive package, including a cable for connecting the IEMs, and a big range of replaceable foam earpieces to fit the ear buds. You’ll also find an XLR to 6.3mm adapter for your controller and a single USB to dual micro-USB cable for charging both the transmitter and receiver at the same time.
Xvive throws in some additional earpieces too. These are made from soft silicone (in red, black, white and yellow), which I found dramatically improved the sound quality, bass response and comfort.

Good-quality zipped, hard-walled cases are included, for keeping each part of the system safe. The smallest and arguably most important case holds the IEMs.

T9 in-ear monitors

The Xvive T9 IEMs are clear bud-like housings that contain all the sound-producing hardware. Designed in the US, they feature pro-level audio quality, and a 2m cable with 3.5mm jack feeding the two-pin connectors into the buds.

As I mentioned, there is a range of earpieces that fit onto the IEM units to suit different ear sizes and canal depths. I found that the foam inserts affected the sound quality, but when I tried the silicone earpieces the sound was dramatically improved. It’s funny how something so small can change a product so significantly!
Still, the foam inserts are a useful backup or they can be great for lending other DJs if you are playing back to back or if working with a band member that forgot their IEMs.

U4 transmitter

The transmitter is a small (90gsm) unit with an XLR port that plugs straight into a desk or, using the 6.3mm to 3.5mm jack adpater, into a DJ controller simple-to-use controls and two switches (aux/line and power/mute). You also have selectable channels (up to six), so you can use multiple devices at once – useful when back-to-back DJing, for example, or of course for members of a band.

Speaking of bands, the system operates on the 2.4GHz band but the selectable channels should help to avoid interference. I certainly didn’t have any issues during testing in three different locations.

U4 receiver

The receiver is a belt pack-style unit weighing in at an acceptable 120gsm.
Xvive state a maximum ‘line of sight’ receiving range of 27.5m (90ft). In testing, I found I had more range outdoors than in , that said, for DJs using this product, you’re generally very close to the transmitter, and this will also be the case for bands, I had no issues at any distance when working events.

On the receiver unit you’ll also find a rotary knob for volume, channel selection to match the transmitter, two LEDS which show the signal to transmitter and low battery warning, and a 3.5mm headphone socket with on/off slider switch. On the side is the charging port and a belt clip.

The system

Let’s look at the U4 system in a little more depth. It features high-resolution 24-bit/48kHz audio with a frequency response between 20Hz and 20kHz, along with a signal-to-noise ratio of 107dB and we’re told it delivers “more volume than you’ll ever need.” Meanwhile, the T9 is fitted with two balanced-armature Knowles drivers (one of the industry’s largest and most powerful mid-bass drivers) and a custom-tuned, custom-ported micro tweeter.

With a custom unified crossover, these cutting-edge components have the headroom to accommodate whatever EQ adjustments are needed. Out of the box, the T9 comes perfectly balanced, with a responsive and detailed sound signature that is not overly hyped or coloured – so even audiophiles will enjoy a fulfilling listening experience.

I’ve used the U4T9 in both indoor and outdoor environments for a wedding and party; the system delivered flawlessly with no noticeable lag in audio transmission.
I also used the system in the office (connected to my Rodecaster Pro) for wedding music prep, and on Teams and Zoom meetings, and the system delivered flawlessly.

All frequencies were easy to hear. Personally, I’d prefer a tad more bass, but that’s probably just the DJ in me. Thanks to the 3.5mm jack, you could easily switch the T9 element to a bespoke moulded option from a different company like ACS, which would give you a personalised product with the T9 kept as a backup.

Battery life

I charged the Xvive U4T9 system as soon as I received it from JHS. I spent some time playing with it in the office and then used it at a wedding. At the end of the event, there was still no low-battery warning, which surprised me because Xvive states five hours of continuous play. As DJs we just cue, mix and turn off the cue or PFL, so this will extend the use time.

I then worked an outdoor event and I still hadn’t charged the battery since first receiving the product. The battery eventually gave up with about an hour left of the event, so out came the headphones (although it’s worth noting you can use the IEMs whilst re-charging).

Based on these tests, I’d guess that as a DJ you could work two standard five-hour bookings from one charge. Although to be on the safe side you’d probably want to charge them for each booking. Using USB, the system charges to full in 1.5 to 2.5 hours. So if you charge as you’re setting up, they’ll be ready to go from the moment you hit play!
I did also try a freshly charged system in the office, listening to music all day whilst working on the computer. The battery was still going strong by the end of the working day, around six hours – so pretty impressive. Although, if you were to leave the PFL open all the time that would probably reduce your use to the manufacturer’s suggested five-hour range.

Overall, the U4T9 is a great product from the team at Xvive! It feels solid and well-made and has opened my eyes to the benefits of using an in-ear system. The price is on point for DJs looking to get into IEMs and the sound quality is perfectly acceptable if you use the correct earpieces. I am very tempted to keep the system and try it for a few more bookings before ordering some custom plugs from ACS.