Lab Gruppen E4:2 - 400 Watt Amplifier with 2 Flexible Output Channels for Installation Applications

Product Overview

The Lab Gruppen E 4:2 is a 400-watt, 2-channel Energy Star certified installation amplifier delivering 2 x 200 W per channel across Lo-Z (2–16Ω) and Hi-Z (70 V) outputs in a 1RU chassis. Designed for light commercial AV applications — including small conference rooms, huddle spaces, and commercial background music systems — the E 4:2 provides flexible per-channel impedance configuration and IDEEA Class-D efficiency in a compact rack-mount package at an accessible price point for smaller deployments.

Product Description

The E 4:2 is the entry-level 2-channel model in Lab Gruppen's E Series installation amplifier line, built on the same IDEEA Class-D platform and Rail Sense Limiter (RSL) technology as the rest of the E Series range. Each channel delivers 200 W at constant voltage 70 V or at low impedance across 2, 4, or 8 ohms. Per-channel mode selection uses the rear-panel RSL switch, allowing independent Lo-Z or Hi-Z configuration for each channel without external transformers. This enables the E 4:2 to simultaneously drive a 70 V ceiling speaker circuit in one zone and a direct-drive low-impedance loudspeaker in another.

The IDEEA output stage achieves operating efficiency above 80%, satisfying Energy Star certification requirements. Auto-standby mode reduces consumption below 1 W after 20 minutes without input signal, with automatic restoration when signal returns. This makes the E 4:2 appropriate for unattended installations such as office background music systems, retail audio, or hotel meeting rooms where power management occurs automatically without user intervention.

The Rail Sense Limiter monitors per-channel rail voltages dynamically, minimizing clipping and protecting connected loudspeakers under variable load conditions. Rear-panel per-channel level trimmers and signal-present LEDs simplify commissioning. A built-in 50 Hz high-pass filter is switchable per channel. GPIO contact-closure interfaces support control system integration. The E 4:2 is designed and engineered in Sweden and includes a 10-year warranty program through authorized dealers.

Key Features

• 400 W Total Output, 2 Channels — 2 x 200 W at 2Ω, 4Ω, 8Ω Lo-Z, and 2 x 200 W at 70 V Hi-Z per channel.
• Energy Star Certified — Operating efficiency >80%; auto-standby <1 W; auto-power-on on signal return.
• Per-Channel Lo-Z / Hi-Z Configuration — Each channel independently configurable for low-impedance or 70 V constant-voltage via rear-panel RSL switch.
• IDEEA Class-D Output Stage — IntelliDrive technology for efficient, low-heat amplification in 1RU.
• Rail Sense Limiter (RSL) — Per-channel dynamic limiter protects loudspeakers and minimizes clipping under variable loads.
• Asymmetric Channel Loading — 400 W total distributable unequally across channels.
• Built-In 50 Hz High-Pass Filter — Per-channel switchable from rear panel.
• GPIO Integration — Contact-closure GPI/GPO for control system power management.
• 10-Year Warranty Program — Available through authorized dealers; designed and engineered in Sweden.
• 1RU Form Factor — Standard 19" rack-mount; IEC mains input; compact and lightweight.

Typical Applications

• Small conference room and huddle space audio
• Commercial office background music and paging
• House of worship overflow and secondary zone audio
• Government building small meeting room PA
• Training room and classroom audio
• Retail background music (70 V ceiling speaker systems)

Technical Specifications

Frequently Asked Questions

Q: What is the difference between the E 4:2 and the E 2:2?

A: The E 4:2 delivers 200 W per channel (400 W total) vs. 100 W per channel (200 W total) for the E 2:2. Choose the E 4:2 when slightly more headroom is needed for larger rooms, more speaker taps, or loudspeakers with lower sensitivity.

Q: Does the E 4:2 support 100 V constant-voltage systems?

A: The E 4:2 supports 70 V Hi-Z operation. For 100 V constant-voltage systems, the larger E Series models (E 8:2 and above) explicitly support 100 V. Verify system requirements before specifying.

Q: Can the two channels operate in different impedance modes?

A: Yes. Each channel has its own independent RSL mode switch on the rear panel. One channel can operate at 70 V Hi-Z while the other operates in Lo-Z mode simultaneously.

Q: Is onboard DSP included?

A: No. The E 4:2 is an analog installation amplifier. Signal processing should be provided by an upstream DSP processor connected to the balanced analog inputs.

Q: What warranty does the E 4:2 carry?

A: The standard warranty is 3 years covering components and factory workmanship. A 10-year extended warranty program is available through authorized dealers.

Q: Is the E 4:2 suitable for unattended installations?

A: Yes. The auto-standby feature activates after 20 minutes without input signal and auto-powers on when signal returns. The GPIO interface also allows external control systems to manage power state programmatically.