Connections
Speakers
Transformer-Coupled Speaker Connections
Transformer-coupled, constant voltage speaker loads are connected to
their respective load type (i.e., 70V speakers to the 70V terminal, 25V
speaker systems to the 25V terminals) and the COM terminal. Make sure
the selector switch is in the TRANS OUT position. A separate 8-ohm ter-
minal is provided to drive 8-ohm (low-impedance) speakers through an
output transformer tap.
The speaker terminals can accept up to a #10 spade lug and have integral
clamping plates that make wiring easier.
4-Ohm Low-Impedance Speaker Connections
A low-impedance (4Ω) speaker load can be driven directly without trans-
former coupling by connecting the load to the 4Ω terminal and the GND
terminal. Make sure the selector switch is in the DIRECT OUT position.
Bypassing the output transformer and driving the speaker load directly
provides the advantage of better bass response.To maximize the power
delivered to the speakers, their combined load impedance should be 4
ohms. Connecting higher load impedances is electrically acceptable, but
the mismatch in load impedance will cause the speaker load to only
receive a portion of the power that the amplifier is capable of delivering.
It is not acceptable to connect low-impedance speakers to the 70V and
25V outputs.
Note jumper link shorting the
GND to the COM terminal.
Typical connections to a low-impedance
(non-transformer-coupled) speaker load
Typical connections to a 70V
transformer-coupled speaker
Note switch is set
to DIRECT OUT
Note switch is set
to TRANS OUT
6
Note jumper link shorting the
GND to the COM terminal.