ART Pro Audio CX 311

An Active Crossover Designed for Modern Bi-Amplification

In a sound reinforcement setup, an active crossover like the CX 311 sits at the heart of the system to properly distribute the spectrum between amplifiers and speakers. The benefits are twofold: on one hand, you better utilize available power by avoiding amplifying unnecessary frequencies for each driver; on the other hand, you gain clarity and control, especially when the system combines bass reinforcement with satellites dedicated to mid/high frequencies.

The CX 311 fits precisely into this logic: it allows organizing a system into 2 stereo channels (separated lows and highs) while adding a mono Sub channel to concentrate low-frequency energy where it is most effective.

Who Is the CX 311 For and When to Use It?

The CX 311 is particularly suited for users seeking reliable and clear control without complicating the rack: mobile sound providers and DJs, bands, small stages, equipped rehearsal rooms, or fixed installations requiring clean bass management. It perfectly suits systems composed of a bass reinforcement combined with bi-amplified mid/high satellites, where frequency band separation becomes crucial for mix precision.

It is also appropriate when you want to harmonize speakers and a subwoofer that do not naturally "blend": by adjusting the crossover frequency and output levels, you can achieve a tighter low end, a smoother transition between sub and satellites, and better overall coherence.

Controls, Filters, and Settings: Practical Spectrum Management

Main Channels: Clear Separation and Musical Integration

On the main channels, the CX 311 offers a frequency selector from 250 Hz to 6 kHz with 24 dB/Oct Linkwitz-Riley filters. This steep slope promotes a sharp separation between "low" and "high" bands, useful to limit overlap zones and improve clarity, especially at higher volumes.

The output levels allow quick balancing of the two bands, for example if your tops are very efficient in the upper spectrum or, conversely, if you want to add body to the low-midrange without forcing equalization. The independent controls (highs/lows) facilitate tuning according to the room, speakers, and musical program dynamics.

Mono Sub Section: Cleaner, More Controlled Bass

The sub section includes a dedicated output level, a 30 Hz high-pass filter, and a frequency adjustment from 50 to 250 Hz with a 12 dB/Oct Butterworth filter. This setting allows choosing the point where the subwoofer takes over: lower for discreet and clean bass, higher to further relieve the satellites and gain headroom.

The mono Sub is a relevant choice in sound reinforcement because low frequencies are non-directional: concentrating energy in a single channel simplifies tuning and can improve the sense of impact, while maintaining a stable stereo image across the rest of the spectrum.

30 Hz High-Pass and Phase Inverter: Anti-"Rumble" and Polarity Alignment

The switchable 30 Hz high-pass filter on all channels helps effectively eliminate "Rumble" type disturbances: stage vibrations, mechanical noises, non-musical infrasonic content. In practice, this protects power reserves, reduces unnecessary speaker excursion, and makes the bass more intelligible.

The phase inverter is a valuable tool when connecting sub/satellites: depending on subwoofer placement, distance, and acoustics, inversion can improve bass frequency summation at the listening point and avoid a hollow sensation around the crossover frequency.

Technical specifications

Frequency selector	250 Hz to 6 kHz	Dimensions (H x W x D)	44.5 x 482.6 x 139.7 mm
Filter type	24 dB/Oct Linkwitz-Riley	Weight	2.2 kg