Overview

Passive Stereo Equalizer with Tube Makeup Gain

The Manley Dual Main EQ is a modernized, true-stereo evolution of the most respected passive EQ design in professional audio. Built for mix-bus work, mastering chains, and high-end tracking. It delivers authoritative low-end weight, open and musical highs, and dimensional depth - with perfectly matched stereo operation.

The Dual Main EQ combines a passive inductor-based EQ network, high-voltage tube makeup gain, and custom in-house wound Manley Iron transformers into a dual-channel signal path designed to do more than adjust tone. The result is equalization that shapes weight, dimension, depth, and musical cohesion - not just frequency balance. The front-panel labeling supports mid-side workflows, allowing for seamless integration with external M-S encoders and independent equalization of mid and side components, providing the spatial control necessary for professional mastering.

A universal switchmode power supply, compatible with all mains voltages, contributing to the unit's extended headroom and low noise floor. The Dual Main EQ is hand built in California.

The Dual Main EQ is designed to complete and analog master-bus EQ system together with the passive stereo Dual Mid Band EQ. The Dual Main EQ handles lows and highs; the Dual Mid Band EQ handles the midrange. Together they cover the full frequency spectrum with a coherent, matched character - and the Manley sound throughout.

Product Details

  • Classic 3-band passive equalizer design
  • Passive inductor-based equalization - broad, natural, phase-coherent curves
  • High-voltage all-tube signal path - 5751 input stage, 12BH7 output stage
  • Custom in-house wound Manley Iron transformers on input and output
  • True stereo dual-channel operation - Left/Right or Mid/Side compatible (no internal matrix included)
  • Frequency response: flat within ±0.1 dB from 20 Hz–22 kHz, Total response: 10 Hz–70 kHz
  • Output exceeding +30 dBu, 26 dB headroom referenced to +4 dBu
  • THD / Noise: < 0.01%
  • Designed for mix-bus, mastering, tracking, and stem processing
  • Universal switchmode power supply — compatible with all mains voltages
  • 2U rackmount
  • Designed to build a complete analog master-bus EQ system with the Manley Dual Mid Band EQ
  • Handcrafted in California, USA
Format
Stereo / Dual Mono
Topology
Passive EQ
Tube Stage
2× 5751, 2× 12BH7
Frequency Response
20 Hz–22 kHz (flat within ±0.1 dB), 10 Hz–70 kHz (total)
THD / Noise
< 0.01%
Signal to Noise Ratio
96 dB
Max Output
+30 dBu
Dynamic Range
122 dB
Input Impedance
5 kΩ
Output Impedance
150 Ω
Inputs
Balanced XLR, transformer-coupled
Outputs
XLR balanced - transformer coupled, TRS unbalanced - direct coupled
Transformers
Manley Iron (in & out)
Bypass
All-tube path (not hardwire bypass)
Power Supply
Universal switchmode
Dimensions (H × W × D)
88.9 × 482.6 × 177.8 mm, 2U
Weight
5 kg- Origin: Handcrafted in California, USA