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Eliminate Long Mic Level Runs and Splitters
Eliminate Loading Effects on Microphones
Audiophile Quality Preamplifiers
MicLim™ - Mic Level Limiter Prevents Mic Preamp Overload
Two Analog Outputs per channel
Three Simultaneous Digital Outputs - Up to 96kHz Sampling Rate
Up to 16 Units (128 channels) can be controlled via one control line
T HE A PHEX R EMOTE C ONTROLLED M ICROPHONE P REAMPLIFIER SYSTEM
Why Place the Preamps Near the Mic?
THE PROBLEM
THE SOLUTION
Long mic level lines, mic splitters, and multiple inputs
reduce the sensitivity of the microphone and change its
frequency, phase and transient response. This performance degradation is the result of shifts in impedance,
capacitance, and inductance values and is quite audible.
• By placing the 1788A close to the mics and controlling it
•
•
remotely the need for long mic level runs is eliminated.
The noise picked up by long cable runs is no longer boosted
at the end of the lines since the preamp gain has already been
taken at the input of the line.
By providing 5 outputs (3 digital & 2 analog) that are usable
simultaneously the need for mic splitter boxes is eliminated.
Typical set-up for the 1788A in a Live Sound Application
STAGE AREA
Monitor Mix
AUX OUT
AUDIENCE
FOH MIX
CONTROL/METERING
SNAKE
MAIN OUT
1788RC
Remote Controller
MIDI Controller
PC
Model 1788A
Front of House Mixer
Up to 16 1788As
via one control line
MICS
To Recording Truck,
Broadcast Feed,
etc.
TASCAM Format
ADAT Format
AES/EBU Format
KEY
Digital Outs
Line Level
Mic Level
Control Line
Why Remote Control?
Almost all live applications require the monitoring of mic preamp gain. If there isn’t
an engineer sitting next to the preamps on stage, there must be a way to control
them from a remote position. All parameters of the 1788A are remotely or locally controllable. Also, setup, snapshots and recall of presets are quickly and easily available.
The remote control protocol for the 1788A is MIDI and up to 16 units (128 channels) can
be controlled with only one control line.
1788RC Power Supply & I/O Box
There are three ways to control the 1788A remotely:
1) Via the 1788RC - hardware remote controller
2) Via PC or Mac running the 1788SW controller software
(Win 95/98/2000/XP® or Mac OS X® compatible)
3) Via any device that generates MIDI, such as a MIDI
controller, mixer, sequencer or show control system
Audio Quality
The 1788A provides 8 balanced Jensen®
transformer-coupled microphone
preamplifier inputs which offer
audiophile sound quality far in
excess of the mic preamps used in
most mixing consoles. It also
provides two separately trimmable
analog outputs for each channel.
The optional digital output module
allows simultaneous output of 24 bit
AES/EBU, T/DIF® and ADAT® Optical.
1788RC Remote Controller
These A/D converters are selectable
up to 96kHz and are Aphex proprietary “Drift Stabilized” (patented)
which eliminate the need for high
pass filtering in the digital domain.
Because the inputs to the A/D converters are trimmed exactly to the
outputs of the preamp, digital resolution can be maximized without fear
of crashing. This makes the 1788A the
perfect front end to any DAW, fiber
system or digital console.
Aphex Proprietary Technologies
MicLim™ is a patented limiter circuit on the mic output a mic level limiter that speeds setup and makes the 1788A
virtually crash-proof. MicLim allows you to set gain for
maximum noise performance without having to back off for
headroom, and eliminates the need for constant gain riding.
Plus fiber or digital systems can be driven at levels that yield
maximum resolution without fear of overload.
LeNA™, the digitally controlled Low Noise Amplifier, allows
the 1788A’s input gain to be adjusted remotely without noise
or glitches. This patented Aphex circuit changes level in
1/4dB steps with 1dB stops. Other remote controlled preamps
use relay switching with step sizes as high as 10dB. Even a
step size of 1/4dB without LeNA will cause an audible click or
pop that at high gains could be explosive!
1788SW Software for PCs
1788A Rear Panel
Specifications
Audio Specifications
Frequency response:
+ .2dB 19Hz-20kHz
Noise:
-125dBu EIN
THD + N:
.003% @ +4dBu Out
SMPTE IMD:
<.02%
DIM:
<.005%
Crosstalk:
<-96dB
Microphone Inputs
Connector:
8 x 3-pin XLR female
Type:
Jensen® transformer coupled
Impedance:
Balanced, 1.6KΩΩ
Max. input level:
+27dBu (with 26dB pad engaged)
CMRR:
Better than -99dB @ 60Hz, -72dB @10kHz
Phantom power:
48VDC on pins 2 & 3
Analog Outputs
Connector:
Main: 8 x XLR, Aux: DB-25 (TASCAM)
Type:
Main: Servo-balanced, Aux: Balanced
Impedance:
Balanced, 65ΩΩ
Max. output level:
+27dBu
Digital Outputs (optional)
Connector:
AES/EBU: DB-15 male
ADAT Optical: TOSLINK
T/DIF: DB-25
Type:
Drift stabilized 24 bit
Impedance:
110ΩΩ (AES/EBU)
Clock:
44.1, 48 or 96kHz Internal (or External)
Clock connector:
BNC
Test tone:
700Hz 0dBfs, -20dBfs
Headphones
Connector:
TRS jack
Impedance:
8-600ΩΩ recommended load impedance
Remote Control
1788RC Hardware Remote: Full remote control functions, Full metering
and preamp status, Select one of 16 units,
Create, Save,Edit, Recall up to 60 presets
1788SW Software:
(For Windows 95/98/2000/XP® & Mac OS X®)
Full remote control functions, Full metering
and preamp status, Select one of 16 units,
Create, Save,Edit, Recall up to 60 presets,
Assignable up to 20 scenes
MIDI Controller:
MIDI command protocol available for full
remote control, metering and status
Connection:
Remote to 1788:
Ethernet, MIDI
Unit to Unit Linking:
Ethernet Hub
Remote functions:
Input Gain, Main Out Gain, Aux Out Gain,
Polarity, Mute, Low Cut Filter, Mute, Pad,
Phantom Power, Sample Clock, Test Tone,
Group Assign, Snapshot, Recall Presets
Mechanical
Power:
90 to 260V, 60 watts
Net weight:
17lbs.
Dimensions:
3 1/2” x 19” x 13 5/8”
All specifications are subject to change without written notice.
Model 148- Digital Audio Splitter - 8 x 32 AES3 Splitter for 1788A
Up to 192kHz Sampling Rates • 1 DB15 Input Connector • 4 DB15 Output Connectors
Meets Full AES/EBU Input and Output Specification • Adds No Jitter
No Setup Required • Low Cost • High Reliability • Transformer Isolated
Internal Power Supply • 1/2 Rack Package • Available as 110ΩΩ Balanced or 75ΩΩ UnBalanced
Model 148 - Front panel
Model 148 - Rear panel
I M P R O V I N G T H E W A Y T H E W O R L D S O U N D s SM
11068 Randall Street, Sun Valley, CA 91352 U.S.A.
818-767-2929 • Fax: 818-767-2641 • www.aphex.com
Aphex, MicLim and LeNA are trademarks of Aphex Systems Ltd. Windows 95,98, 2000 & XP are trademarks of Microsoft Corporation. Mac OS X is a trademark of Apple Corporation.
ADAT is a registered trademark of Alesis Corporation. Jensen is a registered trademark of Jensen Laboratories. T/DIF is a registered trademark of TASCAM Corporation.
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