Allen & Heath ZED-420 – 20-Channel 4-Bus Analog Mixer with USB

Product Overview

The Allen & Heath ZED-420 is a professional 20-channel analog mixing console designed for live sound reinforcement, broadcast, and multi-track studio recording. Featuring 16 mono mic/line channels with the acclaimed GL2400-derived 4-band EQ, DuoPre microphone preamps, six auxiliary sends, and a 7x2 matrix, the ZED-420 provides the routing flexibility and signal integrity required by demanding production environments. The built-in USB 1.1 audio interface delivers stereo 2-in/2-out connectivity to Mac and Windows computers without additional drivers. For live sound engineers, broadcast operators, and recording studios requiring a full-featured analog console with 100mm faders and direct outputs on every mono channel, the ZED-420 is a professionally engineered solution at a competitive price point.

Product Description

The ZED-420 provides 16 mono channels, each equipped with a Neutrik XLR balanced mic input and a balanced/unbalanced 1/4" TRS line input. Allen & Heath's DuoPre preamps deliver up to 63 dB of mic gain with an EIN of -127 dBu at maximum gain (150-ohm source), a noise specification that competes with dedicated recording preamps. Per-channel 48V phantom power is selectable per input, and each mono channel includes a 1/4" TRS insert point for in-line hardware processing such as compression or gating.

The 4-band EQ on mono channels draws from Allen & Heath's GL2400 design: high shelf at 12 kHz, sweepable hi-mid from 500 Hz to 15 kHz, sweepable lo-mid from 35 Hz to 1 kHz, and low shelf at 80 Hz—all at ±15 dB. A 100 Hz, 12 dB/octave high-pass filter is available per channel. Two stereo input channels add four additional inputs (as two stereo pairs) with 1/4" connectivity for keyboards, playback sources, or stereo effects returns.

Six auxiliary sends—two pre-fader, two post-fader, and two switchable pre/post—provide comprehensive monitor and effects routing. Four balanced group/subgroup outputs with insert points allow submix control and group compression. The 7x2 matrix enables complex output routing for delay fills, broadcast feeds, or secondary PA systems. Main outputs are balanced XLR with insert points, complemented by 1/4" direct outputs on all 16 mono channels for individual track capture to a multi-track recorder. The USB 1.1 port provides stereo send/return to a connected Mac or Windows computer.

Key Features

• 16 DuoPre Mic/Line Channels — Neutrik XLR mic inputs and balanced 1/4" line inputs with up to 63 dB gain and EIN of -127 dBu
• GL2400-Derived 4-Band EQ — Sweepable hi-mid and lo-mid on all mono channels, based on Allen & Heath's professional console heritage
• 100mm Long-Throw Faders — Professional-grade faders on all channels for precise level control
• Six Auxiliary Sends — 2x pre-fader, 2x post-fader, 2x switchable pre/post for monitor and effects routing
• 4 Group Outputs with Inserts — Balanced subgroup outputs with insert points for group dynamics processing
• 1/4" Direct Outputs on All Mono Channels — Post-fader direct outs on all 16 mono channels for multi-track recording
• 7x2 Matrix — Flexible output matrix for secondary PA zones, broadcast feeds, and delay fill routing
• Balanced XLR Main Outputs with Inserts — Stereo and mono master outputs at +4 dBu nominal with hardware insert points
• USB 1.1 Audio Interface — Stereo 2-in/2-out USB audio to Mac and Windows computers, no driver required
• External Talkback Mic Input — XLR talkback input routable to the first four aux sends or all main outputs
• Individual Phantom Power per Channel — +48V phantom power selectable per mic input

Typical Applications

• Live sound reinforcement for clubs, theaters, and mid-size venues
• Broadcast audio mixing for radio, podcast production, and broadcast feeds
• Multi-track studio recording using direct outputs to external recorders or via USB
• Houses of worship requiring flexible aux send monitor routing
• Corporate AV events requiring a full-featured analog console with matrix routing

Technical Specifications

Frequently Asked Questions

Is the ZED-420 rack mountable?

No. The ZED-420 is a desk console and does not include rack mount ears or an optional rack mount kit. It is designed for tabletop placement.

What USB sample rates and bit depths does the ZED-420 support?

The USB 1.1 audio interface supports 32, 44.1, and 48 kHz sample rates at 16-bit depth. It provides 2 channels in and 2 channels out to a connected Mac or Windows computer.

Does the ZED-420 have direct outputs on all channels?

Yes. All 16 mono channels have individual 1/4" TRS direct outputs, providing pre- or post-fader signals for multi-track recording or individual channel processing.

How many insert points does the ZED-420 have?

Each of the 16 mono channels has a 1/4" TRS insert, the four group outputs have inserts, and the stereo main output pair has inserts—32 insert points in total.

Can I use the ZED-420 without a computer?

Yes. The USB connection is optional. The ZED-420 operates as a fully independent analog mixer without any computer connection.

What is the talkback mic input used for?

An external microphone connects to the XLR talkback input, and the signal can be routed to the first four aux sends (for monitor feeds) or to all main outputs simultaneously. Level is adjustable independently.

What is the headroom of the ZED-420 analog path?

The analog path provides +21 dB of headroom. The USB I/O path provides +14 dB of headroom.