Dixon RM-35 User Manual

Dixon Systems

Stereo Rack Monitor

Model RM-35

Owner’s Manual

Dixon Systems Model RM-35

Table of Contents

Table of Contents 1

1-1 Description 2

1-2 Features 2

1-3 Technical Description 2

1-4 Unpacking and Inspection 3

1-5 Mounting

1-6 Heat Dissipation 3

1-7 General 3

1-8 Set Up 4

1-9 Amplifier Specifications 4

1-10 Schematic Diagram 5

1-11 Notes 6

1

Dixon Systems Model RM-35

1-1 Description:

Dixon System’s RM-35 is a self contained, rack mountable, stereo amplifier and
speaker monitor system designed to compliment the NM-250 Newsroom Mixer. The unit
employs a high quality stereo audio amplifier driving two three by five inch shielded
speakers, each in it’s own acoustically treated ‘enclosure’. The result is exceptional
audio quality, very low distortion and outstanding stereo separation. The shielded
speakers, along with the toroidal power transformer in it’s power supply, eliminate the
concern about placing the unit in close proximity to video and computer CRT monitors.

There is only one control on the front panel. This allows the operator to switch
between ‘Stereo’ and ‘Mono’ mode to check phase and mono compatibility. This is
done with true L+R summing and with no change in volume. LEDs indicate Power and
Stereo or Mono mode.

**(The RM-35 is also available with the gain control mounted on the front panel when
it’s not used with the NM-250.)

The RM-35 can be used in newsrooms and editing suites or with modulation
monitors and logging systems. It’s a valuable accessory in a wide variety of facilities
and installations.

1-2 Features:

The RM-35 uses 2 premium quality shielded speakers, each in it’s own ‘enclosure’
inside the unit. The stereo amplifier and power supply are in the center of the unit. To
keep things clean and quiet, 1% low noise metal film resistors are used in the signal
path of the amplifiers. The result is clean, very low distortion audio and a better stereo
image. Audio inputs are on the rear panel and are the ‘combo’ type which accept either
XLR or quarter inch TRS connectors. The gain control is also located on the rear panel.
(See ‘Set Up”)

1-3 Technical Description:

The input stage of the RM-35 is a 5532 configured as a differential amplifier. This
permits either a balanced or an unbalanced source. The unit is designed for a nominal
+4 dB input level. The input stage then feeds a resistive network and an analog switch,
a 4053, followed by a summing amplifier, again a 5532. Gain is set in the following
stage, another 5532 and the output stage is a typical NPN/PNP driver/output pair. The
amplifier drives a pair of 3" by 5" speakers, each in it’s own compartment or ‘enclosure’
which has been acoustically damped. This results in better audio and less vibration of
the enclosure itself.

2