ART CX311

Product overview

The ART CX311 is a stereo 2-way crossover with a dedicated subwoofer section, Linkwitz-Riley filters and a 250 Hz to 6 kHz crossover range, in a fully shielded 1U steel enclosure.

The CX311 features Linkwitz-Riley filters to keep the outputs in phase at all frequencies, which ensures proper acoustic summing of common signals from adjacent drivers in the crossover region. Each channel has its own controls for low and high output levels, a variable crossover frequency from 250 Hz to 6 kHz, a switchable low cut filter to eliminate rumble and a switchable phase invert. Both input channels are combined in the subwoofer section, where you set the frequency below which the summed signal is sent to the subwoofer output. The rear panel has XLR and 1/4 inch TRS connections for the inputs and 1/4 inch TRS connections for all outputs, making the CX311 a crossover solution for stereo PA systems with a subwoofer.

Key features

• 2-way stereo operation
• 250 Hz to 6 kHz crossover range
• Subwoofer section with independent level and frequency controls (50 Hz to 250 Hz)
• Balanced XLR and 1/4 inch TRS inputs
• Balanced 1/4 inch TRS outputs
• Switchable 30 Hz low cut filters and phase invert
• 1U rackmount, fully shielded steel enclosure

Crossover section

Each channel's Frequency control sets the crossover point: frequencies below it go to the low output and frequencies above it to the high output. The main crossover filters are fourth-order Linkwitz-Riley designs (24 dB / octave), giving a sharp roll-off and outputs that sum to a flat response. Low and high output level controls trim each output from -30 dB to +10 dB, and the Phase switch inverts the polarity of the high output.

Subwoofer section

Both input channels are summed for the subwoofer output, with its own level control and a frequency control from 50 Hz to 250 Hz (two-pole Butterworth, 12 dB / octave). This is in addition to the normal signals sent to each channel's outputs. Switchable 30 Hz low cut filters on the low outputs and the subwoofer output reduce subsonic frequencies, tighten up the low end and help to protect amplifiers and speakers.

Place in the system

In most systems the crossover is the last unit before the power amplifiers: from the mixer to an equaliser, from the equaliser to the crossover, from the crossover to the power amplifiers and on to the speaker cabinets. ART notes that crossover points should follow the speaker cabinets' documentation, as high frequency horns can be damaged by lower frequencies than specified.

In the box

• CX311 2-way crossover

ART CX311: frequently asked questions

How many outputs does the CX311 have?

Five 1/4 inch TRS outputs: high and low for each of the two channels, plus a mono subwoofer output.

What filter types are used?

Fourth-order Linkwitz-Riley (24 dB / octave, state-variable) for the crossover and two-pole Butterworth (12 dB / octave) for the subwoofer.

Can I use it in mono?

The two channels have independent controls; channel one is left in a stereo system.

Which mains voltage does it use?

ART states 110-125 V AC, 50-60 Hz, 15 W for USA units, and export units configured for the country of destination.

Where can I buy the ART CX311 in India?

The ART CX311 is available from Shivansh Electronics, Kolkata, West Bengal, India, with delivery across India.

Workflow 1: Stereo 2-way PA with a subwoofer

Live sound and public address systems.

Connections

Setup

1. Set all level controls fully counter-clockwise (-30 dB).
2. Make the connections; channel one is left.
3. Set the crossover and subwoofer frequencies, then raise the amplifiers and crossover outputs slowly with programme running.

Tip: ART's set-up order starts with every level control at -30 dB.

Workflow 2: Protecting high frequency horns

Systems with horn-loaded high frequency cabinets.

Connections

Setup

1. Check the cabinets' documentation for their proper frequency range.
2. Set each channel's Frequency control at or above the recommended point.

Tip: ART warns that horns can be damaged by lower frequencies than specified.

Workflow 3: Adding a subwoofer to a stereo system

Venues adding extra bass to existing full-range speakers.

Connections

Setup

1. Set the subwoofer frequency to the value recommended for the subwoofer (50 Hz to 250 Hz).
2. Trim the subwoofer level against the main system.

Tip: Both input channels are summed for the subwoofer output.

Workflow 4: Tightening the low end

Operators dealing with rumble or subsonic content.

Connections

Setup

1. Switch on the 30 Hz low cut filters for the low outputs and the subwoofer output.

Tip: The filters reduce subsonic frequencies and help to protect amplifiers and speakers.

Workflow 5: Correcting phase problems at the crossover point

Engineers tuning the high and low cabinets together.

Connections

Setup

1. Listen around the crossover frequency.
2. Try the Phase switch in the Invert position if a phase related problem is audible.

Tip: Normally the Phase switch stays in the Norm position.

Workflow 6: Balancing amplifier gains

Systems with different amplifiers or speaker efficiencies.

Connections

Setup

1. Start with the output level controls at 0 dB for the flattest response.
2. Trim individual outputs (-30 dB to +10 dB) to compensate for amplifier gain or speaker efficiency.

Tip: Each output has its own level control.