AlphaTheta’s new HDJ-F9 packs its SonicLink wireless DJ monitoring into a smaller on-ear design for £329.
Wireless headphones aren’t used very often in DJ booths, as Bluetooth adds enough latency to throw off beatmatching. That’s why most DJs still monitor via a wired cable connected to the mixer.
AlphaTheta’s proprietary SonicLink connection aims to address that delay, with the company quoting a latency of just 9ms, a figure that’s 20 times faster than the usual Bluetooth SBC codec and fast enough to scratch.
AlphaTheta also focused on faster headset setup. SonicLink Touch Pairing connects the headphones to a compatible mixer such as the DJM-V5 with a single tap on the unit, provided the mixer is running the latest firmware that enables it.
Compared to the over-ear HDJ-F10, which costs £369, this newer model is £40 cheaper and 71g lighter at 285g, with an on-ear fit for DJs who track with one ear cup.
Inside each cup is a newly developed 40mm driver that reaches into the sub-bass range, while a bass-reflex chamber on top of the housing keeps punches and bass lines tight. The PEEK-PU-PEEK composite diaphragm handles mid and high tones with minimal distortion.
Isolation gets similar attention, with the AlphaTheta claiming to have a higher level of noise-blocking than other headphone models, so DJs can hear the mix in a loud booth without turning up the volume too much.
Sound aside, the construction relies on a die-cast aluminum slider and a flexible silicone headband, while swiveling hangers allow the cups to sit on one ear or on the shoulder between mixes. The headphones have also passed international durability tests.
Between concerts, the Headphones Connect app can change the color and brightness of the status LED, rename the headphones, set auto-shutdown, and assign a button to Siri or Google Assistant. The Find My Headphones option plays a sound to find a lost pair. The iOS version of the app is coming to the App Store later.
That status LED also affects battery life, as the SonicLink lasts seven hours with the light on and nine hours with the light off. Bluetooth lasts for 13 and 25 hours, respectively, and a full charge takes about 2.5 hours.
The HDJ-F9 is on sale now 15 for £329 with a two-year warranty. Nixers without built-in SonicLink will need the HP-TX01 transmitter, sold separately from £109.
Included in the box is a 1.2m coiled cable (in case you want to rely on a wired connection), a 6.3mm adapter, a USB-C charging cable and a carrying case.
