McIntosh MC3500

6
General Information
1. For additional connection information, refer to the
documentation included with any component(s)
connected to the MC3500.
2. Apply AC Power to the MC3500 and other
components only after all the system components
are connected together. Failure to do so may
cause a malfunction of system operations as the
Microprocessor’s Circuitry inside the components
is active when AC Power is applied.
3. When discarding the unit, comply with local rules
or regulations. Batteries should never be thrown
away or incinerated but disposed of in accordance
with the local regulations concerning battery
disposal.
4. For additional information on the MC3500 and
other McIntosh Products, please visit the McIntosh
Website at www.mcintoshlabs.com.
Connector and Cable Information
XLR Connectors
Below is the Pin configuration for the XLR Balanced
Input Connectors on the MC3500. Refer to the
diagram for connection:
PIN 1: Shield/Ground
PIN 2: + Output
PIN 3: - Output
Power Control Connector
The Power Control Input Jack receives Power On/Off
Signals when a component is
connected. The Power Control
Output will in turn provide a +12
volt Output Signal with a current
up to 25 mA. An additional
connection is for controlling
the illumination of the MC3500
Power Meter when connected to a compatible
McIntosh Preamplifier or A/V Control Center Power
Control Output. A 3.5mm stereo mini phone plug is
used for these connections.
Output Terminal Connector
When cables with spade lugs are used
for Loudspeaker Connection, the spade
lugs need an opening of at least 3/10 inch
(7.6mm)
PIN 1
PIN 2
PIN 3
Power
Control
Illumination
Control
Ground
3/10 of an inch
(7.6millimeters)
Introduction
Now you can take advantage of traditional McIntosh
standards of excellence in the MC3500 Tube Power
Amplier. The 350 watt power output will drive any
high quality Loudspeaker System. The MC3500 repro-
duction is sonically transparent and absolutely accu-
rate. The McIntosh Sound is “The Sound of the Music
Itself.”
Performance Features
Power Output
The MC3500 is a Tube Power Amplifier with
a capability of 350 watts into 2-, 4-, or 8-ohm
Loudspeakers with less than 0.3% distortion.
Unity Coupled Circuitry
The MC3500 Power Amplifier uses the famous
McIntosh Patented Unity Coupled Circuit which
provides low distortion, extended frequency response
and cool operating output tubes.
Multifilar Wound Output Transformer
The MC3500 Output Transformer Windings are
part of the Unity Coupled Circuitry. There are three
trifilar wound primaries, one for the cathodes, one
for the plates, and one for the screens. The secondary
winding is wound together with the primary windings.
This provides very close primary to secondary
coupling. The result is flat frequency response and
wide power bandwidth.
Balanced and Unbalanced Input
Balanced connections guard against induced noise and
allow long cable runs without compromising sound
quality.
Sentry Monitor Tube Protection
Sentry Monitor provides protection for the MC3500
by monitoring Output. In the event of a large imped-
ance mismatch, a short circuit at the Output Terminals,
or Tube failure, Sentry Monitor will activate to prevent
potentially destructive levels of current from owing.
Vacuum Tube Sockets
Small Signal Vacuum Tubes Sockets have Ceramic
Base construction with gold plated contacts, providing
protection from atmospheric contamination. Output
Tube Sockets include Air-Pipe cooling at their bases
for long term operation.
Amplifier Gold Plated Connectors
Gold Plated Input Jacks and Output Binding Posts
provide trouble free connections.
Special Power Supply
A very large core Power Transformer and large filter
capacitors ensure stable operation.
Power Guard Screen Grid Sensor (SGS)
Power Guard Screen Grid Sensor™ (SGS) helps
prevent premature Vacuum Tube failure by monitoring
the screen grid current in the EL509S output Vacuum
Tubes. If the current becomes too high, a circuit in
Power Guard SGS™ is activated which then dynami-
cally attenuates the input signal in real time to keep
the Vacuum Tubes operating at safe levels. The right
amber LED will flash when Power Guard SGS is
engaged in protecting the Vacuum Tubes.