Total Audio Control EQ ONE - TAC Parametric 4 Band HF/LF Filters. Amek type EQ

EQ ONE

EQ ONE is one of the first in our flagship “Designed by Langley” series of pro-audio products. Yes, as the name reveals it is designed by Mr. Graham Langley, a name that requires no introduction. The premium quality components are used without any exception to provide the highest performance and most reliable operational life. The PCBs are fully gold plated. Nothing is compromised. EQ ONE follows the topology of the four band parametric equaliser that Graham first used in the Amek M3000 mixing console in 1979. This was later adapted for use in

M1000 and M2500 consoles and formed the basis of the equaliser design in many other Amek and Total Audio Concepts consoles.

As with the original design, 12dB/octave swept high and low pass filters are included. The frequency bands have been revised to be more suitable for a stand-alone equaliser and noise performance has been improved.

The topology differs from many other state variable filter designs in that each band is composed of a 6dB/octave high pass and a 6dB/octave low pass filters with different turnover frequencies. This enables the bandwidth to be varied over a wide range and also facilitates the Bell/Shelf switching on the High and Low frequency ranges. The Q control is disabled when in Shelf mode.

The parametric section and the filters section may be individually inserted in the signal path.

A single LED provides indication of signal level. This has quasi-PPM ballistics and illuminates green for signal present (-18dBu), yellow for signals above +4dBu and red for signals above +18dBu.

specifications:

High pass filter: 20Hz to 400Hz @ 12dB/octave.Low pass filter: 800Hz to 20kHz @ 12dB/octave.High frequency 660Hz to 20kHz, +/-15dB, Q: 0.25 to 1.5 with shelf mode.High mid frequency: 320Hz to 10kHz, +/-15dB, Q: 0.5 to 3.2.Low mid frequency: 100Hz to 3.2kHz, +/-15dB, Q: 0.5 to 3.2.Low frequency: 32Hz to 1kHz, +/-15dB, Q: 0.25 to 1.5 with shelf mode.

Frequency response (EQ out):+/- 0.5dB, 20Hz-80kHz.Phase response (EQ out):+/-20 degrees, 20Hz-80kHz.Maximum input and output (100k load):+27dBu.Internal operating level/headroom:-6dBu/+27dBu.THD&N (EQ in or out, +10dBu input signal):better than 0.05%, 20Hz-80kHz.Noise (no EQ in), 22Hz-22kHz, RMS, 40 ohm source:-103dBu.Noise (typical EQ setup), 22Hz-22kHz, RMS, 40 ohm source: -90dBu.Input/output impedance:20k ohms/75 ohms

Condition Note

Very small marking on Top left screw hole. Looks like it was due to over-tightening in the 500 rack. Very light blemish to the right of the EQ in button. Both are only noticeable at very close inspection.