The TOA E 111 is a single channel, 1/1 octave active graphic equalizer designed
to allow clean, accurate audio equalization for stage, studio, or commercial
applications, while the E 112 is a double channel version.
The E 111 and E 112 provide 12dB of boost or cut at each of its 10 frequencies per
channel, which are centered at ISO 1/1 octave increments from 31.5Hz to 16kHz.
The center frequency of each filter is continuously variable over a range of one
octave and the "Q" of each filter is continuously variable from 1.5 to 8. Its signal
to noise ratio is over 120dB making the E 111 and E 112 one of the quietest
equalizers on the market.
The active bandpass/bandreject filters of the E 111 and E 112 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, high-pass and low-pass filters are provided on the front panel. The
high-pass filter has a slope of 12 dB per octave and its cutoff frequency is 40Hz,
while the low-pass filter has a 12 dB per octave slope and its cutoff frequency is
12kHz.
An input level control on the E 111 or E 112 gives 12 dB of adjustment to allow a
wide variety of input sources. An LED indicator illuminates when either the
input or the output comes within 6 dB 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 smoked plastic security cover is included with the E 111 or E 112 to guard
against accidental disturbance, or intentional tampering when used in fixed
installations.
Inputs and outputs are transformer-isolated and balanced, with both XLR and
1/4" stereo phone jacks. Ground lift switches are provided at both inputs and
outputs to reduce hum and prevent ground loops.
The E 111 and E 112 can be mounted in a standard 19" rack and occupy 5-1/4" of
vertical space. The rugged front panel is made of 1/8" (3mm) cast aluminum,
backed with a 1/8" (3mm) steel liner for added durability.
1. 10 filters per channel on ISO 1/1 octave
center frequencies from 31.5Hz to 16kHz.
2. 12dB boost or cut at each center frequency,
continuously variable.
3. Continuously variable center frequency
control at each frequency over a one octave
range.
4. Continuously variable "Q" control at each
frequency from 1.5 to 8.
5. Signal to noise ratio greater than 120dB.
6. High q u a l i t y , low phase-shift active filters.
7. Precision calibrated, noiseless slide controls
with center detent.
8. Equalizer In/Out switch.
9. High- and low-pass filters.
10. LED peak indicator to detect clipping at input
or o u t p u t levels.
11 Variable input level control to accept variety
of input sources.
12. Automatic EQ bypass circuitry.
13. Transformer-isolated balanced inputs and
outputs with XLR connectors and phone
jacks.
14. Ground lift switches on input and o u t p u t .
15. Smoked, plastic security cover is included.
16. Heavy a l u m i n u m die-cast front panel, stand-
ard 19" rack mountable.
— 2 —
General Description
Features
