Passeq: Introduction to the EQ Plug-in (EN)

The Passeq The original Passeq hardware is the first passive EQ which provides three separate frequency ranges for both boost and cut stages. One famous, if not the most famous, passive design was the Pulteq EQ from the decades of the 1950's and 60's. This EQ sported two frequency bands (low and high frequencies, or LF and HF), and had only a few switchable frequencies to offer. In contrast, the 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 extending throughout the relevant audio frequency range—and that with an unheard of abundance of filter choices. The Passeq Analog Code® Plug-in The fantastic qualities of SPL's Analog Code programming faithfully reproduce the unique sound quality of the original hardware. All the complex interactions between each single filter are reproduced in every detail. One of the peculiarities of passive filter designs is that they can be seen as one big filter — the signal always runs through the whole network. Whenever the settings change, a flow of interactions takes place between the filters, providing the characteristic and unique sound of these EQs — something that will never happen with active EQ designs. -- For more information on SPL hardware and software products please go to http://www.spl.info