The most powerful passive EQ ever.
Made by Brainworx in cooperation with SPL.

The original hardware Passeq was the first passive EQ to provide three separate frequency ranges for boosting and cutting. 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 plugin 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 network. 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 make the SPL Passeq THE plugin to have for mix busses and mastering. Its 10Hz Sub Band and the 16kHz Top band sound truly mesmerizing.


  • Includes 2 Plugins: standard stereo and a mono version for individual tracks
  • M/S processing on board
  • Faithful reproduction of the original hardware’s beautiful-sounding interactions between passive filters.
  • 72 filters on six bands per channel.
  • Emulation of input and output transformers

Audio Examples

Customer Reviews

  • Passeq review

    by Bamboom
    Smooth eq, very transparent and you can dial the frequencies you need to boost or cut easily. The bottom end is so awesome, just brings out a roundness to the track or mix. Great tool, use for mixing… Read More
  • Insane Clarity!

    by Mchangani
    I have the hardware and tried out the demo version of the plugin, I must say the apple does not fall far from the tree! love it on everything! I had to purchase it right after trying it out!
  • Beautiful EQ

    by A.M. Music
    I use this for mastering mostly, but it's great on individual tracks too. A subtle EQ, nothing edgy about it. Lots of bass like a pultec and the high end is silky sweet. The high frequency boost is a… Read More
  • good price-quality ratio

    by Mike
    Sounds good, specially in MS mode. Great emulation
  • Beautiful EQ

    by James Cory
    This is my go to eq for subtle shaping of buss tracks. LOVE it!!!


Supported Plugin Formats
AAX DSP, AAX Native, AU, AAX AudioSuite, VST2, VST3

Supported Operating Systems
Mac OS X 10.9 through 10.13
Windows 7 through 10
Pro Tools 10.3.10 or higher or most VST/VST3/AU-compatible hosts 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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