SpeakerCraft BB1235 User Guide

8

Allows the signal from a source to be distributed to any of the 12 channels
on the amplifier. 

Allows a the signal from a secondary source to be distributed to any of the 12
channels of the amplifier. 

Select either 8

Ω 

or

4Ω

to maximize amplifier performance with a variety of

speaker loads. See the sections titled “Selecting the Impedance Setting” and
“Selecting Bridge Mode” in the “Installation” section for proper setting of this
switch.  

There are three ways to turn the amplifier on and off. Use the following list to
decide which mode will work best for your application. See Diagram 3
below.

Use this selection when you wish to manually turn the amplifier on
and off by using the front mounted power button. 

Use this selection if you wish the amplifier turn on when it receives 
voltage (3-30V A/C or D/C) from an external source and turn off once
that voltage has stopped. Some components have voltage outputs
that are designed for this use. In addition there are devices that can
be used as part of an automated system that will provide voltage to
enable the mode. The voltage source must be connected to the trig-
ger-input jack on the back of the amplifier. 

Use this selection when you want the amplifier to turn on when the
amplifier’s main input receives an audio signal. At the moment that
either the left or right input jacks receive a signal the amplifier is
turned on. Once the signal stops the amplifier waits 3 minutes and
then turns off. 

7

To best understand system design and operation of the BB1235 it is useful to
understand the following terms and features as they relate to the BB1235.

A system design that plays the same source at the same time in all rooms. If a
change is made in one room, the same change takes place in all other
rooms. For example, if a listener changes from CD to Tuner in the bedroom,
the same change will be heard in the kitchen. Note: With the use of volume
controls or speaker switchers the volume of each room can be controlled sep-
arately of the other rooms. 

A system design that allows different sources to be played in each room. A
change in one room can be made without changing the other rooms. For
example the CD player can be heard in the bedroom while the kitchen is
playing the tuner. 

The combining of 2 channels to create one mono channel. It is useful when
more volume is needed in a particular area. 

Component, audio or video, that provides an audio signal. Examples are CD,
VCR, DVD, tape deck and tuner. The source provides the audio information
that is amplified by the BB1235.

A distinct unit of the amplifier that provides output to one speaker. On the
BB1235 the input to each channel can be configured to select from the BUS
INPUT, the AUX INPUT or that channel’s unique CHANNEL INPUT. Two adja-
cent channels can be bridged to provide higher power to one speaker.  

Allows any of the channels to be adjusted independently to raise or lower the
output of each channel. This may be used to control the speaker output in
order to balance different rooms or areas of the system. 

Allows each channel to play a variety of different inputs. Depending on the
switch position the channel amplifies the signal connected to the BUS input,
the AUX input, or its own LINE input. 

When either a BUS or AUX input is selected, this switch is used to direct the
channel to play the left signal from the input “L” or the right signal from the
input “R”, or a combined right and left signal from the input “R+L”.