
EMA 255
49
Bridged loudspeaker connections
The EMA ampli er can also be bridged for a mono con gura-
tion. This allows the ampli er to be used for one or several
subwoofers or mid-range drivers. In this con guration, the
ampli er combines the right and left channel to a single-
channel output (mono output).
Note:
The ampli er can add the right and left signal information
only if the right as well as the left RCA connection were
carried out.
Caution:
In a bridge circuit, the ampli er load must be 4 ohm or
higher. A lower load leads to an overheating or switch-o
of the ampli er and can cause permanent damages.
Adjusting the type and range of the
frequency crossovers
With the EMA 255, the type of frequency crossover (i.e. "Low
Pass" or "Hi-Pass") and the desired entry frequency can be
adjusted. For example, if a pair of subwoofers is to be con-
nected, the low-pass settings shown are required (Fig. 3). The
entry frequency is dependent upon the frequency range of
the loudspeakers (see recommended frequency range of
the loudspeakers).
High-Pass
At a setting of 80 Hz, the ampli er has a frequency range of
80 Hz to 30,000 Hz.
Low-pass frequency control
This control is active if the switch is in the position "Low-Pass",
and allows for setting the desired entry frequency.
Example:
At a setting of 150 Hz, the ampli er has a frequency range
of 10 Hz to 150 Hz.
Bass boost
The bass boost control is used to adjust the bass response
of the ampli er.
The setting options are: 0 dB / +6 dB / +12 dB.
Power-on indicator (PWR / PRO)
Green LED:
Output stage on, regular operating status.
Red LED:
Output stage is electronically switched o due to an error.
Recycling and disposal
Please use the return and collection systems avail-
able to dispose of the product.
Subject to changes
EMA_255_22LG.indd 49EMA_255_22LG.indd 49 29.07.2011 9:16:01 Uhr29.07.2011 9:16:01 Uhr