Shure FP23 Specifications

General Description

The Shure FP23 is a portable, battery-powered microphone pre-
amplifier with phantom power. Designed for high bandwidth 96k/24
digital production, this studio-quality mic preamp is ideal for critical
radio, television, and film production applications.
With its rugged mechanical and electrical construction, compact
size, and high-quality components, the FP23 is extremely durable
and easy to use. This highly reliable mic preamp will provide years
of superb audio performance under the most punishing field condi-
tions.
Features
Audio performance
Maximum of 66 dB of gain, adjustable in eleven discrete
steps for accurate, repeatable gain settings.
Dynamic range exceeding 120 dB.
20 Hz to 50 kHz audio bandwidth.
High immunity to RF interference due to transformers, RF
filtering, and all-metal construction.
High current line output driver capable of driving very long
cable runs.
Transformer balanced
Premium-quality input transformer provides superior sonic
quality and freedom from interference problems.
Custom-designed output transformer provides line driving
ability with freedom from interference problems.
Limiter
Extended range peak limiter uses dual opto-isolators,
making the unit virtually "unclippable."
Battery power
Internal battery power (two AA) for convenient, low cost
power.
Battery life greater than 24 hours.
Durable mechanical construction
High strength extruded aluminum chassis with protective
metal end rails to withstand punishing field conditions.
Easy access battery compartment for quick battery
changes.
Phantom power
Selectable 48-volt and 12-volt phantom power for
condenser microphones.
High pass filter
Two corner frequency settings.
2000, Shure Incorporated
27A8726 (TI)
Model FP23 User Guide
Microphone Preamplifier

Specifications

Gain
0 dB to 66 dB input to output, switch selectable
Gain Accuracy
+0.6, –0.1 dB with reference to front panel gain markings
(150 source, 100k load impedances)
Frequency Response (see graph below)
20 Hz – 22 kHz, +0.1, –0.5 dB
–1 dB at 50 kHz
(relative to 1 kHz level with 150
Equivalent Input Noise
–126 dBu (–128 dBV) maximum
(150 source, flat weighting, 22 Hz – 22 kHz bandwidth for gain settings
of 36 dB or greater)
Output Clipping Level
+22 dBu minimum with 100 k load
+20 dBu minimum with 600
Input Clipping Level
+4 dBu minimum at the 0 or +18 dB gain setting
Dynamic Range
122 dB minimum at the +18 dB gain setting
THD + Noise
0.05% maximum
(from 50 Hz to 22 kHz @ +4 dBu output level,
22 Hz – 22 kHz filter bandwidth, +46 dB gain setting)
Common Mode Rejection Ratio:
100 dB minimum at 80 Hz
60 dB minimum at 10 kHz
Input
Transformer-balanced, 2000
Output
Transformer-balanced, 130
Low Cut
80 Hz or 160 Hz (switch selectable), 6 dB per octave
Phantom Power
12V or 48V (switch selectable) per DIN 45 596
Limiter
Limits to +17 dBu output level
10:1 limiting ratio
5 ms attack time, 100 ms release time
Amber/Red LED indicates limiting/clipping
Internal Voltage Rails
+15 V and –15 V, regulated
Power
2 AA batteries, 24 hours life typical with +4 dBu signal into 600 , no
phantom power
Power LED
Green indicates power and good battery.
Red indicates power and low battery. LED turns red when approximately
4 hours of battery life remain.
Polarity
Mic input to line output is non-inverting
Operating Temperature Range
–18 to 57 degrees C
0 to 135 degrees F
source)
load
input impedance
output impedance
Printed in U.S.A.