JBL 305 MKIII

A Modernized Nearfield Monitoring Reference

The 305 MKIII follows in the footsteps of the compact studio monitors designed to provide reliable monitoring without requiring a large control room. Its 5-inch woofer format is particularly well suited to the constraints of production desks, treated bedrooms, podcast studios and music creation spaces.

This generation retains the principles that have made the series so successful: balanced reproduction, a stable soundstage and sufficiently wide dispersion to work without remaining fixed to the millimeter on the speakers’ axis. The transducers and amplification have been optimized to improve linearity, transient response and low-frequency performance at different listening levels.

An Active Monitor for Mixing, Producing and Checking Your Recordings

The 305 MKIII is suitable for producers, beatmakers, sound engineers, content creators and musicians looking for a pair of nearfield monitors capable of revealing the details of an arrangement. It helps you place vocals, balance reverbs, control panning and assess the balance between kick, bass and harmonic instruments.

Its 5-inch woofer offers a relevant compromise for modest-sized rooms: fast enough to analyze the low-midrange without unnecessarily overwhelming the acoustics of a small space. For electronic productions, deep-bass work or monitoring an LFE channel, it can be complemented by a dedicated subwoofer.

For consistent monitoring, position both monitors vertically, with the tweeters at ear height, forming an equilateral triangle with the listening position. This setup promotes a clear central image and limits phase shifts between the woofer and tweeter.

Precise Monitoring Adaptable to Your Working Environment

Waveguide and Expanded Stereo Image

The Image Control Waveguide optimizes the tweeter’s dispersion to produce a spacious, well-structured soundstage. Sources placed in the center remain sharply focused, while panned elements retain their position in the stereo field. This controlled dispersion makes balancing easier, even when the room’s acoustics are not perfect.

Bi-Amping and Slip Stream Bass-Reflex Port

Each driver has its own Class D amplifier: 41 W for the tweeter and 41 W for the woofer. This bi-amplified architecture provides improved transient control and dynamic headroom suited to production, editing or mixing sessions. The dual-flared Slip Stream bass-reflex port helps extend the low end while reducing air turbulence.

Useful Controls for a Home Studio

The Boundary EQ selector lets you attenuate the low end when the monitor is placed near a wall or set on a desk. The HF Trim control adjusts the high frequencies according to the room’s absorption or reverb. This allows you to achieve more natural monitoring without immediately resorting to complex acoustic treatment.

The balanced XLR and 1/4-inch TRS inputs ensure a clean connection to most professional audio interfaces. A sensitivity switch lets you match the input level to a professional +4 dBu source or consumer equipment operating at -10 dBV.

Technical specifications

Bluetooth	No	EQ	No
Connection	XLR, Jack	Color	Black
Speaker diameter	5"	Quantity	1
Number of speakers	2

Type	two-way active studio monitor	Maximum peak SPL level	108 dB
Woofer	127 mm, or 5 inches	Input sensitivity at -10 dBV	92 dB at 1 m
Tweeter	25 mm, or 1-inch soft-dome tweeter	Audio inputs	1 x balanced female XLR, 1 x balanced 6.35 mm TRS jack
Waveguide	Image Control Waveguide	Input sensitivity selector	+4 dBu or -10 dBV
Port	Slip Stream bass-reflex port	HF Trim	+2 dB, 0 dB or -2 dB from 4.4 kHz
Crossover frequency	1725 Hz, fourth-order Linkwitz-Riley acoustic filter	Boundary EQ	0 dB, -1.5 dB or -3 dB at 50 Hz
Frequency response	49 Hz to 20 kHz, within ±3 dB	Enclosure	15 mm MDF
Frequency range	43 Hz to 24 kHz, at -10 dB	Front panel	injection-molded structural ABS
Dispersion	120 degrees horizontal x 90 degrees vertical	Finishing	matte Black
Amplification	Class-D bi-amplification	Power supply	100 to 240 V AC, 50/60 Hz
High-frequency amplifier power	41 W	Maximum power consumption	127 W
Low-frequency amplifier power	41 W	Dimensions	298 x 185 x 231 mm
Total power	82 W	Net weight	4.73 kg
Maximum continuous SPL level	94 dB