TOA Electronics 1000 Series user service General Description, Features, vertical space

General Description

The E-1231 is a single channel, 1/3 octave active graphic equalizer designed to allow clean, accurate audio equalization for stage, studio, or commercial applications.

The E-1231 provides 12dB of boost or cut at each of its 28 frequencies, which are centered at ISO 1/3 octave increments from 31.5Hz to 16kHz.

The E-1231's active bandpass/bandreject filters are designed for minimum phase shift, and feature smooth slide controls with center detents for easy and

accurate adjustment. (The filters are summed in parallel for reliability, so that

the failure of one filter does not interrupt operation of the others.)

In addition, continuously variable highpass filters are provided on the front panel. The highpass filter has a slope of 12dB per octave and is variable from 15Hz to 300Hz, while the lowpass filter can set for either a 6dB per octave slope or a 12dB per octave slope and is variable from 2.5kHz to 30kHz.

An input level control on the E-1231 gives ±12dB of adjustment to allow a wide variety of input sources. A LED indicator illuminates when either the input or the output comes within 3dB of clipping. In addition to the usual EQ in/out switch, an automatic EQ bypass function provides complete equalization bypass in the event of loss of AC power, and an output muting function suppresses turn- on/turn-off transients.

A security cover is included with the E-1231 to guard against accidental disturbance, or intentional tampering when used in fixed installations.

The E-1231 can be mounted in a standard 19" rack and occupies 3-1/2" of

vertical space.

Features

1. 28 filters on ISO 1/3 octave center fre-	8.	Variable input level control to accept varie-
quencies from 31.5Hz to 16kHz.		ty of input sources.
2. 12dB boost or cut at each center frequen-	9.	Automatic EQ bypass circuitry.
cy, continuously variable.	10.	A security cover is included.

3.High quality, low phase-shift active filters.

4.Precision calibrated, noiseless slide con- trols with center detent.

5.Equalizer In/Out switch.

6.Continuously variable highpass and low- pass filters.

7.LED peak indicator to detect clipping at input or output levels.

11.Filter In/Out switch

12.Lowpass filter can be set for either 6dB/oct or 12dB/oct.

13.Optional input/output transformers that convert electronically balanced input/out- put to transformer balanced input/output.

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