McIntosh MC 2250, Руководство пользователя

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When multiple speakers are to be connected to
the amplifier, the combined load impedance for the
speakers must be calculated. The load must then be
connected to the appropriate amplifier impedance
tap. Use this table to aid in selecting the correct im-
pedance match:
STEREO NORMAL CONNECTIONS
Load
impedance
in ohms
0.8 to 1.6
1.6 to 3.2
3.2 to 6.4
6.4 and up
Connect for:
1 ohm output
2 ohm output
4 ohm output
8 ohm output
If a load impedance is used that is lower than the
output impedance tap, then reduced power and pos-
sible distortion will result. If a load impedance is used
that is higher than the output impedance tap, then
neither the signal nor the amplifier will be harmed
but the power available is reduced.
STEREO CONSTANT VOLTAGE LINE OPERATION:
When speakers are to be used in many different
rooms, or many speakers are needed to cover a large
area with sound, constant voltage line operation can
be used. This is convenient for larger home back-
ground music systems or for industrial installations.
Appropriate line matching transformers must be used
at each speaker location. The 2 ohm output provides
the standard 25 volt constant voltage line output. In
the stereo mode 250 watts is available for each
channel.
STEREO CONSTANT VOLTAGE LINE CONNECTIONS
For output
voltage of
25 volts
Connect for:
2 ohms
MONOPHONIC OR SINGLE CHANNEL OPERATION
When the MC 2250 is used as a monophonic or
single channel power amplifier the two channels
can be combined in two different ways. Both will
combine to produce up to 500 watts but the available
impedances are different. MONO BRIDGE offers a
few higher impedance connections than MONO
PARALLEL. Either mode can be used for 2 or 4 ohm
operation. Performance is identical. Monophonic
constant voltage line operation can also be used.
The outputs are connected as described below.
When using the MONO BRIDGE mode, output im-
pedances of 2, 4, 8, and 16 ohms are accomodated.
Output connections are made by connecting to the
output terminals as listed below. Note that neither
output terminal is at ground potential.
MONO BRIDGE CONNECTIONS
Load Impedance
In Ohms
2
4
8
16
Connect - Speaker
Lead To:
Left 1 Ohm Terminal
Left 2 Ohm Terminal
Left 4 Ohm Terminal
Left 8 Ohm Terminal
C Speaker
Lead To:
Right 1 Ohm Terminal
Right 2 Ohm Terminal
Right 4 Ohm Terminal
Right 8 Ohm Terminal
When using the MONO PARALLEL mode, output
impedances of ½ , 1, 2, and 4 ohms are ac-
comodated. Connect as listed below. The common
output terminals are at ground potential.
MONO PARALLEL CONNECTIONS
Load Impedance
In Ohms
½
1
2
Connect - Speaker
Lead To:
Either Left or Right
Common Terminal
Either Left or Right
Common Terminal
Either Left or Right
Common Terminal
Either Left or Right
Common Terminal
C Speaker
Lead To:
Both Left and Right
1 Ohm Terminals
Both Left and Right
2 Ohm Terminals
Both Left and Right
4 Ohm Terminals
Both Left and Right
8 Ohm Terminals
MONOPHONIC CONSTANT VOLTAGE LINE
OPERATION
When the MC 2250 is used in MONO for constant
voltage line operation, the MONO PARALLEL con-
nection is used. The appropriate line matching
transformers must be used at each speaker location.
The 1 ohm connection provides the standard 25 volt
constant voltage line output. In this mode a total of
500 watts of monophonic power is available.
MONO CONSTANT VOLTAGE LINE CONNECTIONS
For output
voltage of
25 volts
Connected for:
1 ohm output (mono), mono parallel
Be certain that the MC 2250 is never operated in
the stereo mode with the outputs connected for
monophonic operation. Should the MODE SWITCH
be left in the STEREO position and the outputs re-
main strapped for a mono parallel load, one channel
will attempt to drive the other which causes high cir-
culating currents and overheating.
AC POWER
The MC 2250 operates on 120 volts 50/60 Hz and
requires 12 amps at full rated output. Plug the power
cord into a suitable source. The auxiliary AC
OUTLET on the MC 2250 is not fused or switched.
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