Rane MS 1b User Manual

DATA SHEET

General Description

The Rane MS 1b Mic Stage preamplifier provides the
answer when you need just one microphone input in an
otherwise line-level world. Give us a call to go from either a
dynamic, condenser or electret microphone to a line-level
input with a minimum of noise, distortion, cost and hassle.

The MS 1b provides 48 V switchable Phantom Power with
indicator LED, continuous rotary Gain trim between 18 dB
and 66 dB, Signal/Overload LED, and XLR balanced Input &
Output connectors. A Polarity switch and high-current cross­coupled output line driver round out the features.

The MS 1b utilizes one of the finest ultra low noise
amplifier designs available. Featuring a true differential input
with high common-mode rejection, use of the MS 1b guaran­tees performance usually found only in mixing consoles
costing thousands of times as much. Of course, for all of that
extra money you receive a proportional increase in KPSI
(knobs per square inch).

MS 1b

MICROPHONE STAGE

Features

•

New! Improved Max Input

•

New! Improved dynamic range

• Gain control

• Signal and Overload indicators

• Polarity switch

• Switchable 48 V Phantom Power

• Ultra low-noise design

• True differential Input

• Cross-coupled line driver

• UL/CSA/CE and 100/120/230 VAC remote power supply

Data Sheet-1

MS 1b

MICROPHONE STAGE

Features and Specifications

Parameter Specification Limit Units Conditions/Comments

Input Impedance 10k 1% ohms Balanced 5k + 5k
Gain Range 18 to 66 typ. dB
Phantom Power +48 4% volts 10 mA max.

..........Impedance 6.81k 1% ohms Each leg

..........Load Regulation 0.1 typ. % 0 to 14 mA

..........RMS CM Noise .003 typ. % % of Vout (10 to 10k Hz)

Max. Input Level +10/-32 min. dBu Gain 18/60, balanced output
Equivalent Input Noise -128 typ. dBu 20 kHz BW, Rs=150 ohms, Gain = 60 dB
Signal to Noise Ratio 96 typ. dB 20 kHz BW, Rs=150 ohms, Gain = 18 dB, re 4 dBu
Dynamic Range 120/95 typ. dB Gain 18/66
CMRR 80 typ. dB Rs=150 ohms, 120 Hz, Gain = 60 dB
Frequency Response

..........Gain 60 dB 45 to 200k typ. Hz +0, -3dB

..........Gain 18 dB 30 to 200k typ. Hz +0, -3db

THD+Noise (gain 60 dB) .007 (Output=+20 dBu) typ. % 55 to 20k Hz, 20 kHz BW, Rl=10k ohms
THD+Noise (gain 18 dB) .001 (Output=+20 dBu) typ. % 50 to 20k Hz, 20 kHz BW, Rl=10k ohms
Line Driver Active Cross-coupled Gain 5.2/6 dB typ. unbalanced/balanced
Max. Output Level +22/+27 min. dBu Unbalanced/balanced, 2k ohm load
Output Impedance 50 1% ohms Each Leg
Signal Indicator 2/8 typ. dBu Unbalanced/balanced output, Green LED
Overload Indicator 14/20 typ. dBu Unbalanced/balanced output, Amber LED
Output Cable Length 300 typ. meters Belden 8451 or equivalent
Unit: Agency Listing

..........120 VAC model Class 2 Equipment National Electrical Code

UL & CSA Exempt Class 2 equipment

..........230 VAC model CE-EMC EMC directive 89/336/EEC

CE-Safety Exempt per Art. 1, LVD 73/23/EEC
Power Supply: Agency Listing Class 2 Equipment

..........120 VAC model UL File no. E88261

CSA File no. LR58948

..........230 VAC model CE-EMC EMC directive 89/336/EEC

CE-Safety LV directive 73/23/EEC

..........100 VAC model Built to JIS Japan only

Power Supply Input 18 VAC w/center tap 10% Vrms Rane RS 1 supplied
Max Current Consumption 220 mA
Unit Size 1.65" H x 5.1" W x 4.25" D (4.2 cm x 13 cm x 10.8 cm)

..........Weight 1 lb (0.45 kg)

Shipping Size 3.6" H x 11.75" W x 7.2" D (9.5 cm x 30 cm x 18 cm)

..........Weight 4 lb (1.8 kg)

Data Sheet-2

Block Diagram

MS 1b

MICROPHONE STAGE

Application Information

Uses and applications for the MS 1b should be obvious.
But then again, it’s obvious to us our taxes are too high and
nothing is being done about that. With this in mind, perhaps a
few words on using the MS 1b might not be wasted.

BALANCED USE

The MS 1b provides a true cross-coupled balanced output.
This is equivalent to an electronic simulation of a transformer
output. Rane follows the AES standard of pin 2 = hot.

When running a long cable back to the mixer, run a line-
level balanced line rather than a mic-level line. The compact
MS 1b can mount closer to the microphone, provide a local
volume control (or not, just pull the knob off), while the
stronger signal minimizes RF and hum irritations.

UNBALANCED USE

Balanced use is recommended to minimize noise. When
you must drive an unbalanced device with the MS 1b's
balanced output, connect pin 2 to the “+” or “hot” lead, and
tie pin 3 and ground together at the shield.

MIXING

The MS 1b is designed to fill the need for adding a
microphone channel to line-level mixers, such as the Rane
SM 26B or SM 82. Many installations using either of these
products invariably wind up with one unused input that would
do the job perfectly if only it could operate at mic-level. In
rides the MS 1b to the rescue.

DIGITAL RECORDING AND SAMPLING

Another handy use for the MS 1b is in recording applica­tions. Many popular products do not have a high enough
quality mic preamp to suit the resolution of the digital
processing electronics. Such irony. Using the ultra low noise
MS 1b to bring the mic inputs up to extremely high quality
line-level is an easy and affordable solution for this dilemma.
No garbage in; no garbage out. Clippity-clop; clippity-clop.

MICROPHONE TYPES

The available gain and large input range of the MS 1b
allows the use of virtually any type of microphone. True 48V
phantom power guarantees the MS 1b works with every
microphone. The better the mic, the better the MS 1b sounds.

Ah, the sound of the thundering hoofs is deafening.

Data Sheet-3

MS 1b

MICROPHONE STAGE

Architectural Specifications

The microphone preamplifier shall be a single channel
stand-alone unit with remote power supply. The power supply
shall be U.L. listed, C.S.A. certified, and CE certified. The
input and output shall be fitted with XLR connectors. A
polarity inverting switch shall be included. Phantom power
shall be provided in compliance with IEC 60268-15 and be
controlled by a slide switch with an LED indicator. A gain
control shall be provided with 18-66 dB adjustment range.
Power, system signal and overload indicators shall be
provided. High current cross-coupled active output line driver
shall be standard, as well as input RFI filter protection.

The unit shall be a Rane MS 1b Microphone Stage.

CHASSIS GROUNDING

Units with outboard power supplies do not ground the
chassis through the line cord. Make sure that these units
are grounded either to another chassis which is earth
grounded, or directly to the grounding screw on an AC
outlet cover by means of a wire connected to a screw on
the chassis with a star washer to guarantee proper contact.

Please refer to RaneNote 110, “Sound System Inter­connection” (supplied in your manual and available on
request separately) for further information on system
grounding.

©Rane Corporation 10802 47th Ave. W., Mukilteo WA 98275-5098 TEL [phone] FAX [phone] WEB http://www.rane.com

Data Sheet-4

All features & specifications subject to change without notice. DOC 104514 PN 11801