The EMI TG12412 was first introduced to the recording world around 1972 when Abbey Road installed the first TG12410 Transfer (or mastering) Desks. This equalizer is deeply rooted in the tradition of EMI eqs started in 1954 with the RS56, and continued with the TG12345 in 1969, and finally the TG12412 in 1972.

The eq has 20 selections on the four bands as well as five shapes per band. Shelf low, blunt, medium, and sharp bell curves, and shelf high. One of the interesting and highly prized uses of the TG12412 is the shelf high and shelf low settings. On each band you can choose to shelf up or down on any frequency and this is an often used trick of Abbey Road mastering engineers through the years. Another interesting feature is that all eq points are based on the note C and are spaced in half and third octaves based on that. It is thought that this is part of the totally musical sound of the equalizer.

The eq selection in detail-
Section 1- 32, 45, 65, 91, 128 Hz. +/10db boost or cut in 1db steps.
Section 2- 181, 256, 362, 512, 724 Hz. +/-10db boost or cut in 1db steps.
Section 3- 1.02, 1.45, 2.05, 2.6, 3.25 kHz. +/-10boost or cut in 1db steps.
Section 4- 4.1, 5.8, 8.1, 11, 16 kHz. +/-10 boost or cut in 1db steps.

The EMI TG12414, was first introduced to the recording world around 1972 when Abbey Road installed the first TG12410 Transfer (or mastering) Desks. This special sounding equalizer and filter has been a highly prized secret of Abbey Road engineers for nearly 30 years.

Each unit includes high pass, low pass and presence and presence controls as well as the MKIV TG Line Amplifier. The Presence control provide 10db of boost or cut on eight frequencies that are approximately the same shape as the medium setting on the TG12412 Mastering Eq. It should also be noted that these are the same eq points as the TG12345 console eq as used on many Beatles and Pink Floyd recordings. The high and low pass circuits are 18db per octave and provide four and five selections respectively.

The eq and filter selection in detail-
Presence- .5, .8, 1.2, 1.8, 2.8, 4.2, 6.5, and 10 kHz with +/-10 of boost and cut in 1db steps.
Low pass- 20, 15, 12, 10, and 8 kHz at 18db/octave.
High pass-40, 63, 80, and 110 Hz at 18db/octave.