AlphaTheta HDJ-F9

A wireless DJ headphone designed for the next generation of performances

With the HDJ-F9, AlphaTheta offers a compact DJ monitoring headphone that meets the demands of today’s performances: mobility, quick setup and reliable monitoring in the booth. It reflects a modern approach to DJing, where wireless connections need to deliver precision comparable to wired listening.

Its main strength lies in the proprietary SonicLink technology. It enables high-quality audio transmission with extremely low latency, down to 9 ms, so you can prepare transitions, beat-match tracks and scratch with a natural feel. The HDJ-F9 combines the freedom of wireless operation with the responsiveness essential for mixing.

A reliable partner for club DJs, mobile artists and demanding creators

The AlphaTheta HDJ-F9 is designed for DJs looking for headphones that are easy to carry, comfortable during long sessions and precise enough for working in a busy booth. It is equally suited to experienced DJs performing in clubs, mobile artists, event hosts and enthusiasts looking to upgrade their monitoring equipment.

Thanks to its swivelling earcups and flexible headband, it easily adapts to each user’s habits. One-ear monitoring feels natural when checking the next track while staying connected to the sound system. Worn around the neck between transitions, the headphones remain comfortable.

Its Bluetooth connection expands its possibilities beyond performances: music listening, playlist preparation, track analysis or everyday use with a smartphone. For mixing and situations requiring immediate synchronisation, the SonicLink connection is particularly well suited.

SonicLink, Bluetooth and personalised settings for unrestricted monitoring

The HDJ-F9 is equipped with 40 mm dynamic drivers capable of delivering dense, energetic bass without masking important mix information. The mids and highs remain balanced, making it easier to distinguish vocals, percussion, cymbals and rhythmic elements, even when the booth volume increases.

SonicLink technology offers a range of up to approximately 15 metres in open space. The headphones can be instantly paired with compatible DJ equipment using the SonicLink Touch Pairing function: simply bring the HDJ-F9 close to the compatible device to establish the connection. With the separately sold SonicLink HP-TX01 transmitter, it can also be connected to many other devices.

Bluetooth 5.3 ensures a stable connection with everyday devices and supports the A2DP, AVRCP, HSP and HFP profiles, as well as the SBC and AAC codecs. The HEADPHONES CONNECT app lets you customise the color and brightness of the status indicator, rename the headphones, adjust the automatic power-off setting and assign a command to Siri or Google Assistant.

Built to accompany DJs over the long term, the HDJ-F9 features a die-cast aluminium adjustment slider and a structure that has passed international durability tests. Wired listening is also possible thanks to the supplied coiled cable, making it ideal for maintaining a direct connection depending on the setup.

Technical specifications

Format	supra-aural	Adjustable headset	Yes
Design	closed	Frequency response	5 Hz - 30 kHz
Impedance	32 Ω	Color	Black

Type	closed-back dynamic headphones	SonicLink battery life with indicator light on	approximately 7 hours
Drivers	40 mm dome	SonicLink battery life with indicator light off	approximately 9 hours
Sound pressure level	106 dB	Bluetooth battery life with indicator light on	approximately 13 hours
Weight	285 g without cable	Bluetooth battery life with indicator light off	approximately 25 hours
SonicLink latency	up to 9 ms	Headphone charging time	approximately 2.5 hours
Maximum SonicLink range	approximately 15 m in open space	Charging connector	USB Type-C
Bluetooth	version 5.3	Compatible app	HEADPHONES CONNECT
Maximum Bluetooth range	approximately 10 m in open space	Available settings	status indicator, headphone name, automatic power-off and voice assistant control
Compatible Bluetooth profiles	A2DP, AVRCP, HSP, HFP	Warranty	2 years
Compatible Bluetooth codecs	SBC, AAC