Z&H Designs 1178 Mastering Stereo Peak Limiter

The Z&H Designs 1178 Mastering Stereo Peak Limiter is a mastering-focused evolution of the classic 1178 FET compressor, developed in response to community demand for greater precision, flexibility, and modern workflow features. Built around the same signal path and rare electrical components as the original UREI design, this mastering version adds stepped controls, ultra-tight channel matching, onboard Mid/Side processing, and parallel compression. The result is a faithful yet forward-looking stereo limiter capable of pristine transparency, bold character, or anything in between.

Key Features

• Mastering-grade version of the Z&H Designs 1178 Stereo Peak Limiter.
• Exact signal processing chain and rare components matching the original UREI 1178.
• Stepped controls across all primary parameters for precise recall.
• Channel matching accuracy within 0.1 dB for mastering standards.
• Onboard Mid/Side and Left/Right operation with independent channel control.
• Parallel compression via dedicated mix control.
• Sidechain high-pass filter with selectable frequencies.
• High-headroom linear power supply for stability and low noise.

Mastering Workflow Enhancements

• 21 stepped positions on Input, Output, Attack, and Release controls.
• Independent attack and release per channel for meaningful M/S processing.
• Capable of operating as two independent mono FET compressors in L/R mode.
• Mix control enables controlled parallel compression for modern loudness workflows.
• Sidechain HPF options at 0, 60 Hz, 120 Hz, and 180 Hz to preserve low-end clarity.

Circuit Design & Sonic Character

• Rare and discontinued components, including NPD5566 FET transistors.
• Limited-production build due to component availability.
• Capable of extremely clean compression compared to vintage units.
• Wide tonal palette through ratio button combinations beyond all-buttons-in.
• Designed to handle aggressive compression while remaining musical.

1166 Output Transformer

• Custom hand-built 1166 output transformer inspired by classic Neve designs.
• Replicated mold and construction for 100% accuracy.
• Enhances harmonic richness, smooths dynamics, and reinforces low-end weight.

Power & Build Quality

• High-quality linear power supply for low noise and consistent performance.
• Designed for long-term reliability in mastering and professional studio environments.
• Each unit individually tested and signed by experienced engineers and craftspeople.

Specifications

• Frequency Response (Compressor & SFE Bypassed, Unloaded): 20 Hz – 40 kHz (±0.5 dB typical)
• Maximum Output Level (Bypassed, Unloaded): +27 dBu typical
• Total Harmonic Distortion + Noise
• 20 Hz, +20 dBu: <0.15%
• 1 kHz, +20 dBu: <0.025%
• 20 kHz, +20 dBu: <0.0075%
• Compressor Controls
• Threshold: −58 dBu to +28 dBu
• Ratios: 4:1, 8:1, 12:1, 20:1
• Blend (Mix): 0% – 100%
• Attack: 20 μs – 800 μs
• Release: 50 ms – 1.1 s
• Noise Floor
• 22 Hz – 20 kHz SNR: −86.3 dBV
• Power
• AC Power Consumption: 50 W max
• Voltage Selector: 110V / 220V
• Fuse: 5 × 20 mm, 2A fast-acting glass
• Physical
• Product Dimensions (H × W × D): 8.8 × 48.4 × 27.4 cm
• Shipping Dimensions (H × W × D): 22.3 × 58.2 × 45.4 cm
• Shipping Weight: 9.5 kg (20.9 lbs)