Crest Audio reserves the right to make improvements in manufacturing or design which may affect specifications.
9/4/01
v.1.5
Architects’ & Engineers’ Specifications:
INPUTS:
There will be two microphone and one stereo
line input, each with rear panel jacks. Each low
impedance microphone input will be a female
XLR connector, and will have switchable 48V
phantom power (with LED indication), and 20
dB pad, and polarity switches. Mic pre-amps
will be adjustable from +10 to +56 dB of gain
by a potentiometer and have an EIN of 128
dBu @150 ohms. Two mic enable switches
(with LED indication) will be provided. The
stereo line input will be TRS balanced and high
impedance, suitable for use with an electric
guitar (200K ohms) or standard line level
inputs, and have 1/4" will have a gain adjust-
ment range from off to +20 dB. There will be
two TRS insert jacks that function for both line
and mic inputs. They are located on the rear
panel and have a front panel enable switch
with LED indication.
EQUALIZATION:
In series with each microphone preamp will be
a defeatable third order high pass filter with a
corner frequency range of 75Hz. Two fully
adjustable stereo parametric equalizers will be
provided with a –24dB to +12dB boost/cut
range and a bandwidth adjustment of 2
octaves to 1/6 octave. They will have a fre-
quency range of 40 Hz to 15 KHz. Each para-
metric will have an enable switch with LED
indication. The second parametric filter will
additionally have a switch that will move its
position out of the main audio path and into the
compressor’s side-chain (after the side-chain
insert jack’s return).
DYNAMICS:
The IPro Two will have an adjustable dynamics
section that will have a linked stereo compres-
sor, expande, and limiter. The expander will
have threshold (-80 dBu to +10 dBu) and ratio
(1:1 to 1:5) controls. The compressor will have
threshold (-40 dBu to +20 dBu), ratio (1:1 to
infinite:1), and make-up gain (0 dB to +20 dB)
controls. Both will be soft knee circuitry. The
limit will have only a threshold (0 dBu to +22
dBu) control with a red "active" LED. A twelve
step gain reduction LED array will indicate for
all three dynamic functions. There will be two
side-chain TRS insert jacks at the rear with a
front panel enable switch with yellow LED. The
side-chain inserts will be connected before the
second parametric EQ (when it is switched into
the detector path) so that external signals may
benefit from it.
There will be a dynamics enable switch (with
green LED) on the front panel which allows all
dynamics functions to be bypassed.
SmarTube:
Included in the IPro Two is a high frequency
enhancement circuit that adds transtube har-
monics to improve definition and add presence
to the signal. There will be a tuning control with
an adjustment range of 2kHz to 10kHz, and a
level control.
OUTPUTS:
There shall be a master output level control
with a gain range of OFF to +10dB.
Independent of this control will be a head-
phone level control with the same gain range,
and a front panel headphone jack. A blend
control will pan between the dry preamp signal
and the wet post processing signal to allow a
compressed frequency shaped signal to be
blended with the original input to fatten the
bass or add a high frequency sheen. A twelve
segment LED output meter array will be includ-
ed. It will monitor either the pre-amp signal (to
assist in setting the mic input gain or line level),
or the main output, determined by a selector
switch. The output jacks will consist of 1/4"
unbalanced and a XLR balanced jacks, on the
rear panel. The mains input will be an IEC con-
nector.
Frequency Response:
Total Harmonic Distortion plus Noise (THD+ N):
Signal to Noise (all functions enabled, all levels at
nominal, mic input at min gain):
MIC Equivalent Input Noise (EIN):
Common Mode Rejection Ratio (Mic Input):
Meters:
Dimensions:
Weight:
Power Requirements:
Mic Input to Output: 15Hz to 45KHz +0dB / -1dB
Line Input to Output: 10Hz to 35KHz +0dB / -1dB
< 0.01% 20Hz to 20KHz Mic to Output (10Hz - 80KHz BW, dry)
< 0.02% 20Hz to 20KHz Mic to Output (10Hz - 80KHz BW, dynamics enabled)
88 dBu
-129 dBu (Input terminated with 150 Ohms)
77dB typ @ 1kHz, max gain
12 segment gain reduction indication
12 segment peak reading output (0dB= 0dBu @1/4" out, +4dBu @ XLR out)
19" W x 9.5" D x 3.5" H
8.7 lbs
DOM: 120VAC 60Hz 15 Watts Nominal
EXP: 230VAC 50/60Hz 15 Watts Nominal
