We get a lot of people in the studio that ask questions about what are the differences between the various EQ’s that we have and how does one differ from another. We thought that we would quickly explain here the different types of EQ that we use here at A Sharp Recording Studios; EQ’s that are not in the computer, actual outboard that we use on a day to day basis at the studio.
The simplest types of EQ are those that are passive, with no active circuits that boost frequencies, but rather have components that subtract from the frequency audio source. The EQP-1A is one of the earliest types of EQ, being originally designed by Western Electric in the 1930’s, and were initially designed to allow music to pass through telephone systems. The wide EQ curves associated with an EQP-1A explain this as one can boost low frequencies and high frequencies and filter out noise. Whilst not perfect for all audio sources this wide EQ curves have been described as “very musical”. Eugene Shenk of Pulse Technologies re-discovered the EQ in the 1950’s and added a vacuum tube make-up gain amplifier. EQP-1A’s tend to be simplistic in design and have no headroom problems and little distortion, as they are passive, subtracting from the source. In terms of operation the EQP-1A’s are useful on most sources such as kick, bass and we use them to warm up a voice in the DAW. The EQP-1A allows you to boost the low frequencies and attenuating the lower mid frequencies at the same time, just above the low frequency part you have boosted.