RDL STMLDA3 Installation Guide

STICK-ON® SERIES

Model STM-LDA3
Studio Quality Mic Preamp
with Distributed Outputs

ANYWHERE YOU NEED...

• Studio-Quality Mic Preamplification

• Three Distributed Line-Level Outputs

• Ultra Low Noise

• Ultra Low Distortion

• Selectable Filtered Phantom Voltage

• Adjustable Gain up to 60 dB

• Versatility of STICK-ON Compactness

• RDL’s Exclusive Dual-LED VU Metering

You Need STM-LDA3!

The STM-LDA3 is part of the group of versatile STICK-ON products from Radio Design Labs.
STICK-ONs feature the advanced circuitry for which RDL products are known, combined with unequalled
versatility in mounting possibilities. The durable adhesives provided with the STM-LDA3 permit
permanent or removable mounting. Numerous available mounting accessories, brackets and rack-mount
chassis are optionally available to facilitate any system design.

APPLICATION: The STM-LDA3 is designed for use in quality commercial sound, broadcast and
recording applications. The 1200 Ω balanced input accepts a wide variety of microphone input levels
without loading professional low-impedance microphones. A multi-turn gain trimmer allows precise output
level adjustment. The output signal is available on three separate balanced line-level outputs. Each
output may be connected balanced or unbalanced.

RDL’s exclusive low-noise discrete preamplifier circuitry produces studio-quality low-noise performance in
an economical preamplifier. Dynamic or condenser microphones may be used with the STM-LDA3.
Standard 24V phantom is supplied to the input when the supply voltage is connected to the PHM terminal.
Optimum operating level is set using RDL’s unique Dual-LED VU meter, located adjacent to the terminal
block. A green LED illuminates at 15 dB below a +4 dBu output. The intensity of the green LED
progresses from minimum to full intensity at +4 dBu. The adjacent red LED illuminates when the operating
level exceeds +4. This makes the STM-LDA3 easy to set up without any external test equipment and
operating levels may be monitored at the module.

Wherever a mic to line level distribution amplifier or studio quality microphone preamplifier is needed, the
STM-LDA3 is the ideal choice. Use the STM-LDA3 individually, or combine it with other RDL products as
part of a complete audio/video system.

RDL • 659 N. 6th St. • Prescott, AZ., USA 86301 • [phone] • FAX [phone] • www.rdlnet.com

STICK-ON® SERIES

Model STM-LDA3
Studio Quality Mic Preamp

OUTPUTS

B

OUTPUTS

B

C

OTHER
BALANCED
OR UNBAL

OUTPUTS

C

with Distributed Outputs

STUDIO QUALITY PREAMPLIFIER

MIC INPUT 3 LINE OUTPUTS

G

A
I
N

SIGNAL

BALANCED
MIC-LEVEL

SOURCE

G

A
I
N

FROM

PHM

INPUT PWR

STUDIO QUALITY PREAMPLIFIER

MIC INPUT 3 LINE OUTPUTS

PHM

INPUT

SIGNAL

FEEDING
BALANCED
LINE LEVEL

EQUIPMENT

PWR A

A

WIRING

L
E
V
E
L

ADJUSTMENT

SUPPLY

WIRING

L
E
V
E
L

AUDIO

25 TURN

GAIN SET

Installation/Operation

EN55103-1 E1-E5; EN55103-2 E1-E4

Typical Performance reflects product at publication time
exclusive of EMC data, if any, supplied with product.
Specifications are subject to change without notice.

STUDIO QUALITY PREAMPLI FIER

G

INPUT PWR

A

I

N

SIGNAL

FROM

UNBALANCED

MIC-LEVEL

SOURCE

G

INPUT

A

I

N

MIC INPUT 3 LINE OUTPUTS

PHM

STUDIO QUALITY PREAMPLI FIER

MIC INPUT 3 LINE OUTPUTS

PHM

PWR A

OUTPUTS

A

B

SIGNAL

FEEDING

UNBALANCED

LINE LEVEL

EQUIPMENT

OUTPUTS

B

C

OTHER
BALANCED
OR UNBAL

OUTPUTS

C

L
E
V
E
L

L
E
V
E
L

OPTIONAL JUMPER

TO PROVIDE PHANTOM

POWER TO CONDENSER

MICROPHONES

RDL PS-24

TYPE

SUPPLY

24 VDC

POWER

SOURCE

TYPICAL POWER

CONNECTION

(24 VDC PHANTOM)

24 VDC

POWER

SOURCE

TYPICAL PHANTOM

TYPICAL PERFORMANCE
Input: 1200 Ω balanced
Outputs (3): +4 dBu, 150 Ω balanced
Gain: 40 to 60 dB (25 turn trimmer adjustable)
Frequency Response: 30 Hz to 20 kHz (+/- 0.2 dB)
THD + N: < 0.1%
IMD: < 0.1%
Noise: < -70 dB (below +4 dBu @ 60 dB gain – wideband)

< -80 dB (below +4 dBu @ 50 dB gain – wideband)
Equivalent Input Noise: < -130 dB (gain + residual noise below +4 dBu)
Headroom: > 20 dB (above +4 dBu)
CMRR: > 60 dB (100 Hz to 5 kHz)
Power Requirement: 24 - 33 Vdc @ 40 mA, Ground-referenced

Radio Design Labs Technical Support Centers

U.S.A. [phone], [phone]; Fax: [phone]

891-1085A

Europe [NH Amsterdam] (++31) 20-6238 983; Fax: (++31) 20-6225-287

CONNECTION