Meyer Sound Control Electronics Unit S-1

To Next Page

S-1

Control

Electronics

Unit

Operating Instructions

Meyer Sound Laboratories, Inc.

2832 San Pablo Avenue

Berkeley, CA 94702

The Meyer Sound S-1 is

a single-channel active

signal processor de-

signed for use with the

USM-1 Loudspeaker. It

occupies a single 1

⁄4-

inch rack space.

The functions of the S-1

are:

• Active crossover for

biamplification

• SpeakerSense™

driver protection with

MultiSense™ function

• True excursion limit-

ing to protect the

USM-1 drivers

• Loudspeaker fre-

quency and phase

response alignment

Connections

The S-1 operates at line level and is intended to be the

final component in the signal chain before the power

amplifier. Connections between the S-1 and the power

amplifier should be made according to the diagram

above.

1. Signal inputs to the S-1 may be either balanced or

unbalanced. For best signal-to-noise ratio, use balanced

connections operating at +4 dBu nominal. The S-1 will

accept peak input levels up to +26 dBu balanced, or

+20 dBu unbalanced.

Note: The S-1 utilizes Meyer Sound’s exclusive ISO™

Input. Pins 1, 2 and 3 are transformer-isolated, and the

connector shell is connected to earth ground. The Input

GND/ Lift switch controls the connection between pin 1

and circuit common, which is tied to AC/chassis ground

through a 500 ohm resistance. If hum problems occur,

this switch may be used to control ground loops in the

system.

2. SpeakerSense™ connections are made from the

output of the power amplifier back to the S-1 Sense in-

puts. The Hi output of the power amplifier must be con-

nected to the Hi Sense input, and the Lo output of the

power amplifier to the Lo Sense input .

The Sense connection must be made in order for the

driver protection circuitry to operate properly.

Note: The S-1 Sense inputs incorporate Meyer Sound’s

exclusive MultiSense™ function, which allows use of

multiple power amplifiers driven in parallel from a single

S-1 and having different voltage gains and/or power

ratings. The S-1 accommodates up to two power amplifi-

ers, and provides a separate Sense input for each. The

MultiSense circuit automatically tracks the power ampli-

fier with the greatest output swing to control the system

protection circuitry. These inputs are polarity-sensitive:

be certain that they are connected with correct polar-

ity, as indicated on the S-1 rear panel.

3. Signal outputs from the S-1 are active balanced at

+4 dBu nominal operating level, with pin 1 tied to earth/

chassis ground through a 500 ohm resistance. The maxi-

mum output level is +26 dBu balanced (+20 dBu unbal-

anced).

4. Connections between the power amplifier output and

the USM-1 should be made in accordance with the

USM-1 Operating Instructions. These connections

must be verified for correct polarity and correct channel

assignment (Hi to Hi, Lo to Lo).

PUSH

+–

PUSH

Input

Lift

GND

Input

Hi Sense

Lo Out

Hi Out

1/4 A SloBlo

90-105

105-125

210-250

180-210

AC Voltage

90-250 VAC

50-60 Hz

100mA MAX

CAUTION:

Set voltage before applying power.

AC Voltage Ranges

210 - 250

180 - 210

105 - 125

90 - 105

Lo Sense

Hi Channel

PUSH

+–

Lo Channel

Amplifier

Loudspeaker Cable

Input

Need help?

Do you have a question about the Meyer Sound Control Electronics Unit S-1 and is the answer not in the manual?

Summary

S-1 Control Electronics Unit Overview

S-1 Functions

Key functions include active crossover, SpeakerSense driver protection, excursion limiting, and frequency/phase alignment.

Connections

Details on signal input, SpeakerSense connections, and output configurations, including ISO input and polarity sensitivity.

Operation and Controls

System Operation

Procedure for powering on the system, setting amplifier levels, and adjusting S-1 attenuation for system sensitivity.

Preset Panel Controls

Explanation of controls like Safe switch, VHF switch/control for frequency response, and Lo Cut filter.

SpeakerSense Driver Protection

How SpeakerSense monitors driver voltage and activates limiters, with indicator descriptions.

Advanced Operation and Setup

Limiter Operation Verification

Steps to verify limiter functionality using an oscillator or microphone and observing indicator lights.

Balancing Amplifier Gain

Procedure for setting equal voltage gain between Lo and Hi amplifiers using an oscillator and voltmeter.

Specifications

Input and Output Specifications

Details on input/output types, levels, impedance, and connector types for the S-1 unit.

Performance Specifications

Includes hum/noise, dynamic range, crossover frequency, and driver protection parameters.

Physical and Power Details

Information on power requirements, physical dimensions, weight, and control features.