The most powerful passive EQ ever! The original hardware Passeq was the first passive EQ to provide three separate frequency ranges for both boost and cut. The Pultec EQ, the famous passive EQ from the 1950’s and 60’s featured just two frequency bands, and had very limited switchable frequencies. SPL’s Passeq has 12 switchable frequencies per band, totaling 36 boost and 36 cut frequencies! Boost and cut frequencies are NOT identical, thus the resultant 72 frequencies per channel offer an enormous choice for the most elaborate EQ curves. The Passeq offers, for the first time, passive filter control possibilities with an unheard of abundance of filter choices.

The fantastic quality of SPL’s Analog Code programming faithfully reproduces the unique sound characteristics of the original hardware Passeq. All the complex interactions between each single filter are faithfully preserved in every detail. One of the unique qualities of passive EQ designs is that the audio signal reacts to the multiple bands as one big filter. Whenever a setting changes, the entire interaction between EQ bands occurs. This provides the unique characteristics and very special sound of these EQs — something that simply does not happen with active EQ designs.

The combination of all this filtering power, mastering grade sonic quality, and advanced M/S processing (a software-exclusive feature!) make the SPL Passeq THE plugin to have for mix busses and mastering.

Download a fully functional 14-day demo today to hear for yourself! (No dongle required!)


  • Includes the standard stereo and a mono version for individual tracks.
  • M/S switch allows for separate processing of M (Mid) and S (Side) signals.
  • Faithful reproduction of the original hardware’s beautiful-sounding interactions between passive filters.
  • 72 filters on three bands per channel.
  • Emulation of input and output transformers.
  • Adds an amazing M/S mode which the hardware doesn´t offer.
  • Four individual “Settings” can be stored for quick A/B comparison, or to automate different settings at different points in the material.
  • Mouse Wheel Control over rotary controls.

Audio Examples

Customer Reviews

  • ★★★★★
    by Allister Whitehead
    You don't need to add much bass to get that all important oomph required for a dance track, cleanish and big. The mid section sounds solid and rich without any +DB. The top end adds a subtle sheen… Read More
  • ★★★★★
    by JimHam70
    SPL makes some great products. This is one of them. It's like having a Pultec on steroids. Put the MEQ-5 & the EQP-1A together, add M/S and a few more bells & whistles and you'll have the PassEQ.… Read More
  • ★★★★★
    by John DeLorme
    I have never used the Passeq hardware unit, but I have used many a passive hardware EQ's. True to their form, this digitally modeled passive EQ is super smooth and sounds awesome. I love the top and… Read More
  • ★★★★★
    SPL Passeq
    by seb
    Really love this transparent eq.
    The possibility to unlink after the result is near what I want, and acheive eache side sepperatly is really grate to me.
    I also like that some freq… Read More
  • ★★★★☆
    by DukeTt
    Great eq, not for intricate work but gives sounds a little something extra when pushed at certain frequencies. Useful on summed busses in particular.
    Awesome GUI and functionality, only wish… Read More


Supported Plugin Formats
AAX DSP, AAX Native, AU, AAX AudioSuite, Venue 32-bit, VST2, VST3

Supported Operating Systems
Mac OS X 10.8 through 10.13
Windows 7 through 10
Pro Tools 10.3.10 or higher or any VST/VST3/AU-compatible host running on a supported operating system

Intel CPU only (minimum 2 GHz recommended)

Intel-compatible CPU with SSE2 instruction set (Pentium 4 compatible or higher; minimum 2 GHz recommended)

System Requirements
Display resolution: 1440 × 900px or 1280 × 960px or higher
Memory: 2 GB RAM


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