Passive equalizers
History
Filters are among the oldest electronic audio effects, dating back to the beginnings of
phonographic recording and reproduction. They were first used to correct spectral distortions in
sound reproduction systems, and later for aesthetic purposes. The first filters were fixed, but a
variable equalizer arrived in the 1920s (created by John Volkman for the RCA company), kicking
off a spectacular evolution of these tools throughout the 20th century.
Before the democratization of the transistor, the first equalizers were made of passive networks
followed by tube amplification cells. For cost reasons, several filters were implemented on the
same passive components network, often in parallel. The Pultec EQP-1 equalizer, still widely
used today in studios around the world, is probably the best representative of this technology
and has achieved mythic status among audio engineers.
Pulsar Massive is an emulation of a famous passive equalizer released at the dawn of the 21st
century, itself largely inspired by the Pultec EQP-1. Passive equalizers are characterized by a
rich and smooth sound. The use of inductances in the passive circuit causes characteristic
behaviors, particularly in the low end of the spectrum: the higher the input level, the greater the
likelihood that harmonics and ‘dynamic’ behavior will appear. This behavior allows, for example,
to work on the low mids (100-500Hz) without the sound becoming muddy as is often the case
when using other EQs in this frequency zone.
With Pulsar Massive, you get:
The sound of a legendary EQ unit that’s used in studios all over the world
Musical equalization, either as an insert effect or on a bus
Unique warmth and dynamic behavior (due to our emulation of the original circuit's
inductors and tube amplifier stages)
Very smooth and musical equalization curves
An innovative workflow that allows you to tweak equalization directly on a graphical curve
An organic analog sound paired with the advantages of digital (presets, automation of
parameters, etc.)
Pulsar Massive - User Manual - page 6 / 35
