Product details

The SPL Audio PQ is a high-end, dual-channel analogue mastering equalizer designed for precision tonal shaping in professional mastering, mixing, and recording studios. Built around SPL’s proprietary 120 V Rail Technology, it delivers exceptional headroom, low distortion, and detailed signal processing. Each channel features five fully parametric equalisation bands with independently adjustable frequency, gain, and bandwidth, allowing engineers to make subtle tonal refinements or precise corrective adjustments. Its selectable Constant Q and Proportional Q modes, stepped controls, and automatic bypass functionality make it an ideal tool for critical mastering applications where accuracy, repeatability, and musical flexibility are essential.

Key Features

Dual-Channel Design: Operates as a stereo equalizer or processes two independent mono signals.
Five Fully Parametric Bands per Channel: Dedicated LF, LMF, MF, MHF, and HF bands for comprehensive tonal shaping.
Selectable Constant Q and Proportional Q: Switch each band between precise corrective equalisation and musical, bandwidth-dependent processing.
Wide Frequency Selection: LF: 10 Hz–330 Hz; LMF: 33 Hz–1 kHz; MF: 128 Hz–4.1 kHz; MHF: 310 Hz–10.2 kHz; HF: 760 Hz–24 kHz.
Adjustable Gain: Up to ±20 dB of boost or cut per band, with a 1/4 Gain switch reducing the range to ±5 dB for finer mastering adjustments.
41-Step Detented Controls: Precise, repeatable settings for frequency, gain, and Q.
Independent Band Switching: Activate or bypass individual EQ bands for detailed processing and comparison.
Automatic Bypass: Adjustable automatic switching supports objective evaluation of processed and unprocessed audio.
Channel Link Function: Link selected controls across both channels for convenient stereo operation while retaining dual-mono flexibility.
SPL 120 V Rail Technology: High-voltage analogue circuitry designed for exceptional headroom, dynamic range, and low distortion.
Balanced Analogue Connectivity: XLR inputs and outputs for professional studio integration.
Maximum Input Level: +32.5 dBu.
Maximum Output Level: +32.5 dBu.
Input Impedance: 20 kΩ.
Output Impedance: 75 Ω.
Frequency Response: 10 Hz–100 kHz (−3 dB).
Total Harmonic Distortion plus Noise: 0.0005% at +30 dBu, 1 kHz.
Dynamic Range: 135 dB.
Noise: −94.3 dBu, A-weighted.
Power Supply: Internal linear power supply with shielded toroidal transformer; selectable 115 V or 230 V AC operation.
Power Consumption: Maximum 100 VA.
Rack Format: 19-inch rackmount, 4U.
Dimensions: 482 × 177 × 300 mm (W × H × D).
Weight: 15.2 kg.
Manufacturing: Designed and manufactured in Germany.