Allen&Heath 21 Series - Manual (Page 2)

AUDIO QUALITY
Advanced low-noise circuitry boasts a high
slew rate of 13 V/ uS, permitting faithful
reproduction of transient information. Each
mixer is supplied complete with its own
external power supply to ensure that hum
fields are kept to a minimum. Phantom power
is available as an optional extra. As the
comprehensive PFL system overrides all
monitor outputs and metering, easy checks
may be made on all incoming and outgoing
signals.
MONO OUTPUT
Invaluable as an extra on-stage foldback mix
or as a feed to a mono PA system, permitting
the main stereo faders to be used as
sub-groups or outputs to a stereo recorder.
This feature will be of particular interest to the
AV or broadcast user who may need a
dedicated mono output for simultaneous video
recording, or mono transmission.
PRO AND SEMI-PRO CAPABILITY
21 SERIES mixers are supplied with outputs set
for OVU= +4dBm, but external links are
provided so that outputs and tape monitor
inputs can be adjusted by the user (or the
dealer) to ensure compatibility with
equipment designed for lower operating
levels. A thoughtful facility that will make life a
lot easier for the small budget studio. All-steel
construction provides strength and good
electrical screening.
PLUGABILITY
Rear panel sockets provide bus access points
for stereo and mono outputs, cue and echo
sends, and the PFL system. Thus, two or more
21 SER IES mixers may be conveniently linked
for single operation, greatly increasing the
input potential and all-round flexibility of this
new range.
INPUT CHANNEL FEATURES
* Electronically-balanced transformerless
microphone input on XLR socket, switchable
to a high impedance balanced line input when
required.
* Effects insertion point that can also be used
as a line level input or as a spare effects send.
* 20dB pad switch.
* 3 Band equaliser with mid-frequency sweep
from 400Hz to 6kHz.
* Pre-fade cue send and post-fade echo send.
* Channel pan pot and PFL Selector.
*LED peak overload indicator and smooth
travel, long throw fader, providing a high
degree of operator control.
OUTPUT SECTION FEATURES
* Twin illuminated VU meters with associated
PFL override LED indicator.
* Two echo returns, each with PFL, cue send,
level and Pan.
* Cue and echo send masters, both with PFL.
* Main Left and Right outputs and mono output
on XLR sockets (all featuring PFL selectors).
MONITOR FACILITIES
The two independently-controlled stereo
outputs to headphone and monitor amplifier
can be switched to Mono. An off-tape return
from a stereo recorder may also be selected,
enabling A/B monitoring during recording.
TECHNICAL SPECIFICATION
MIC INPUT +20dB to +60dB (PAD -2 0dB) 1.5kohm
Equivalent Input Noise - 125.5 dBm
LINE INPUT -5dB to +36dB (PAD -12dB) 1 0kohm
(Further 10dB gain available at fader)
EQUALISATION HF 10kHz (shelving) +/- 15dB
MF 4 00Hz- 6kHz (Q = 1.4) +/- 13dB
LF 100Hz (shelving) +/- 15dB
HARMONIC DISTORTION typically <0.05%
OUTPUT Unbalanced 30 ohm source impedance
Recommended load greater than 2kohm
Maximum output +2 1dBv
DIMENSIONS Model 621 458 x475x100 Model 1221
674 x475x100 Model 1821 891x475x100