ART Pro VLA III

Product overview

The ART Pro VLA III is a two-channel optical compressor with a real 12AT7 tube, switchable tube or solid state voicing and dual mono or linked stereo operation.

Like the earlier models, it is an optical compressor with two channels that can be used independently or linked for stereo operation. It offers musical control of dynamics that can smooth out individual tracks or glue a full mix together, using a fixed-input, variable-threshold design with the character of a real 12AT7 tube. The Voice switch selects a warm tube or a clean solid state signal path, and the ratio range reaches down to 1.25:1 for gentle compression in mastering. ART has increased the headroom, lowered the background noise and improved the channel symmetry in linked stereo mode, and the front panel has been refreshed. Variable threshold, ratio, attack, release and output controls, independent bypass per channel and simultaneous metering of input level, output level and gain reduction complete the all-analog design.

Key features

• Two-channel optical compressor with a soft-knee levelling design
• Switchable tube and solid state voicings with the Voice switch
• Input, output and gain reduction metering: backlit VU meters, 10-segment LED gain reduction meters and an LED input level meter
• Variable threshold, ratio, attack and release
• Dual mono or linked stereo operation with master output and balance controls in Link mode
• 12AT7 tube
• +4 dBu or -10 dBV operation
• Hardwire bypass per channel
• Universal internal power supply, 100-240 V

Optical compression with a choice of voice

The Pro VLA III uses the optical method of level detection, which ART describes as very musical: it adjusts to changes in signal level much as the eye adjusts to light. It is a soft-knee levelling amplifier by design, capable of dramatic compression effects but built to excel where transparent, musical dynamics control is wanted. The Voice switch routes the signal through the 12AT7 tube to warm the source and clip peaks musically, or through the more precise solid state circuit.

Controls and metering

Each channel has Threshold, Ratio (1.25:1 to 20:1), Attack (0.25 ms to 50 ms), Release (150 ms to 3 s) and Output controls, a Voice switch and a Comp (bypass) switch. Large backlit analog VU meters show the output level, fast 10-segment LED bars display gain reduction, and the centre LED bar shows the average input level with peak hold. In Link mode, channel one's controls set both channels, the channel one Output knob becomes the master level and the channel two Output knob becomes a balance control.

Connections

The rear panel has balanced XLR and 1/4 inch TRS inputs (10 kΩ) and active balanced XLR and 1/4 inch TRS outputs (100 Ω) for each channel, and a switch to select +4 dBu or -10 dBV operation. The bypass is passive (hardwire), so the signal passes from input to output even when the power is off. Power enters through a rear IEC connector with the mains fuse in its pull-out drawer.

Applications

ART names tracking, mixing, mastering, live sound and broadcast audio in professional and home studios. The Pro VLA III works as a compressor or limiter in digital or analog recording, in a mixer's channel insert points, between a microphone preamp and signal processors, and between pre-amplified instruments and other line level equipment. Used as a mastering device it can add warmth and impact and prevent transients from causing digital clipping.

In the box

• Pro VLA III
• QuickStart manual
• IEC power cord

ART Pro VLA III: frequently asked questions

Can the two channels work as a stereo pair?

Yes. The Stereo Link switch ties both channels to the channel one controls, so each side of a stereo signal is processed identically; the channel two Output knob then becomes a balance control.

What does the Voice switch do?

It selects the warm 12AT7 tube path or the clean solid state path for each channel.

Can I connect a microphone directly?

No. The inputs are designed for line level signals; ART states that microphones must connect through a microphone preamplifier first.

Does the bypass work with the power off?

Yes. The bypass is passive (hardwire), so the signal passes from input to output even when the unit is off.

Which mains voltage does it accept?

The internal universal power supply accepts 100-240 V, 50 Hz / 60 Hz (25 W).

Where can I buy the ART Pro VLA III in India?

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

Workflow 1: Stereo bus compression while mixing

Mix engineers who want to glue a full mix together.

Connections

Setup

1. Press Stereo Link so both channels follow the channel one controls.
2. Lower Threshold until the yellow (0) gain reduction LED begins to light, then set Ratio for the amount of compression.
3. Use the channel two Output knob as the balance control.

Tip: Link mode processes both channels identically, so the stereo image does not shift.

Workflow 2: Gentle mastering compression

Mastering and pre-mastering of finished mixes.

Connections

Setup

1. Link the channels.
2. Start with a low ratio, down to 1.25:1.
3. Choose the tube or solid state voice to suit the material.

Tip: ART notes that as a mastering device it can add warmth and impact and keep transients from causing digital clipping.

Workflow 3: Vocal levelling while tracking

Studios recording vocals.

Connections

Setup

1. Connect the microphone through a preamp: the inputs are line level.
2. Set Threshold and Ratio while watching the gain reduction meter.
3. Adjust Attack and Release to keep the performance natural.

Tip: ART names about 6 dB of attenuation as good for controlling peaks; more than 20 dB means heavy compression.

Workflow 4: Two independent mono channels

Engineers compressing two different sources at once.

Connections

Setup

1. Leave the Link switch in Dual.
2. Set each channel's controls and voice separately.
3. Use each channel's Comp switch to compare with the bypassed signal.

Tip: Each channel has its own hardwire bypass.

Workflow 5: Insert on a mixing console channel

Live sound and studio consoles with insert points.

Connections

Setup

1. Select +4 dBu or -10 dBV on the rear I/O level switch to match the console.
2. Set Threshold, Ratio, Attack and Release for the source.

Tip: ART lists mixer channel insert points among the Pro VLA III's uses.

Workflow 6: Line level instrument levelling

Players of keyboards, guitars and bass with a preamp.

Connections

Setup

1. Run the instrument into a preamp ahead of the Pro VLA III for a stronger signal and less noise.
2. Use a slower attack to keep the instrument's attack, and heavier gain reduction to add sustain.

Tip: ART recommends a preamp ahead of the unit rather than plugging an instrument in directly.