B&K 125.5 S2 User Manual

The Reference 125.5 S2 or Reference 125.7 S2 allows signal patch cables (interconnects) to be sourced
from either balanced or unbalanced preamplifier/processor outputs. A switch is used to configure a PAIR of
AMPLIFIER CHANNELS for use with either balanced (XLR) or unbalanced (RCA) outputs. 

There are five balanced (XLR) input connectors on the Reference 125.5 S2 and seven balanced (XLR) input
connectors on the Reference 125.7 S2. These connectors accept balanced output from the preamplifier's bal-
anced output connectors.

There are five unbalanced (RCA) input connectors on the Reference 125.5 S2 and seven unbalanced (RCA)
input connectors on the Reference 125.7 S2. These connectors accept an unbalanced (RCA) output from the
preamplifier's (RCA) volume level outputs.

C H A N N E L 2 I N P U T

C H A N N E L 3 I N P U T

R C A ( U N B A L A N C E D )

X L R ( B A L A N C E D )

2

1

3

PIN 1 (GND)

PIN 1 (GND)

PIN 3 (-)

PIN 3 (-)

PIN 2 (+)

PIN 2 (+)

Balanced Interconnect Cable

1

2

3

PIN 1 (GND)

PIN 1 (GND)

PIN 3 (-)

PIN 3 (-)

PIN 2 (+)

PIN 2 (+)

Amplifier Balanced Input Connector