PASSEQ is the second generation of SPL’s acclaimed dual channel passive mastering EQ and brings some exciting new feature flourishes along with the unbeatable sound and build quality SPL fans have come to expect.

A Mastering Evolution

SPL’s first revolutionary passive mastering equaliser was the first ever to offer high, mid and low band manipulation with independent controls for boost and cut in a per-band format. With 36 boost and cut frequencies across 12 selectable frequencies, this surmounted to almost three million unique curves available to the lucky mastering engineer in command.

In its second generation, PASSEQ inherits the same number of boost and cut frequencies, but with individual selections geared towards even more musical results and an optimised Q for each selectable frequency.

A Second Helping

The number two generation PASSEQ has been designed to incorporate all of the modern design traits and refinements that mastering engineers demand for intuitive workflow and even better masters.

The new model features Air band as well as a new mid cut band at 200Hz, whilst output controls have been upgraded to stepped potentiometers ranging from -10 to 10dB for ease of recall between sessions.

Internally, original capacitor arrays used in SPL’s first generation model have been switched out for custom-designed caps offering more optimised bandwidth.

Riding The Rails

As with all of SPL’s highest end products, PASSEQ is powered by proprietary 120V rail technology offering unprecedented headroom, improved dynamic range and near undistortable audio presentation.

SPL’s 120V circuitry is able to operate at roughly twice the voltage of regular discrete op-amps found in other audio equipment, allowing it to deliver superb technical and sonic performance.

The PASSEQ is a truly adept tool for heavy duty mastering jobs, and bestows a completely natural feel on any track it touches while reducing listening fatigue for the professional user.


Max Input Level:
+ 32.5 dBu
Input Impedance:
20 kOhms (balanced)
Max Output Level:
+ 32.5 dBu
Output Impedance:
‹ 600 Ohms (balanced)
Harmonic Distortion:
0.076% @ -30 dBu; 0.026% @ -20 dBu
- 91.8 dBu (unweighted, (Gain +0 dBu)
› 102 dB (Gain +0 dBu)
Common Mode Rejection:
› -60 dBu @ 1 kHz, Gain +0 dBu
Transmission Bandwidth:
10 Hz - 200 kHz (-3 dB)
Frequency Range:
10 Hz - 35 kHz


0.06 Amp, 230V/50Hz
230 V/50 Hz: 0.5 Amp

Physical Properties

482 x 177 x 311.5mm
10.2 kg

Main Features

  • Next generation passive mastering technology
  • Independently controllable 3-way bands
  • Separate frequency, boost and cut controls
  • 12 frequencies per band
  • Improved 2nd gen frequency selections and Q
  • New 25kHz and 35kHz Air band frequencies
  • Mid range cut starting at 200Hz
  • Precision detented potentiometers (ALPS RK27)
  • Powered by SPL’s high-headroom 120V rail technology
SSP (inc VAT) £ 4,299.00
EAN 4260149321725