Martin Audio – MA1.3s Amplifier
ENGLISH
11
CH. B
CH. A
INPUT
INPUTCH.A LINK
CH.B LINK
GA IN
41dB
38dB
35dB
32dB
29dB
26dB
23dB
20dB
678
123
GA IN
CH.B
GA I N
CH.A
LINK / BRIDGE A+B
ON
OF F
Current consumption: 8.7A
230-240V 50-60Hz
Must be grounded
XLR
Pin 1 Scrn Sleeve
2 Pos Tip
3 Neg Ring
1/ 4“
STEREO
Th e inp ut im ped ance is hig h eno ugh (20k oh ms ba lan ce d) to allow ”d aisy-cha in ing ”, or mu ltiple p ara llel inp ut
co nn ection s. Th e h ea dro om of th e inp ut circu its will also accep t the ma xim um ou tpu t level from virtu ally a ny lo w-level
sign al sou rce. Balan ced sign als are less sen sitive to A C h um an d rad io interference. Th e sou rce im pe dan ce sh ould b e
le ss th an 1k oh ms to avoid h igh freq uen cy lo sse s if lon g cab le run s are used .
To daisy chain amplifiers, use the XL R-m ale conn ector, labe le d Link, provided o n e ach chan nel. It is co nne cte d in
pa ra lle l w ith the Ne utrik Co mb o jack on e ach in pu t.
7.1.2 Unbalanced inputs
To connect an unbalanced source, tie pin 3 (ring on TRS jack) down to the shield of the connector. If you leave one
pin disconnected, you will lose 6 dB.
A better method for using unbalanced sources is shown in Figure 8. This is similar to the connection for balanced
lines, but pin 3 is connected to the shield at the source. The hum and noise rejection for the cable is equivalent to
that for a balanced line. To minimize hum in the audio, use balanced inputs whenever possible.
Unbalanced line connection
Balanced line with unbalanced equipment
For two-channel (stereo) operation, use both channels A and B. For tandem stereo or bridged mono operation, use
only one of the inputs. See operating modes for more details.
7.2 Connecting speakers
Speaker connections are made via the two Neutrik NL4FC Speakon connectors. The Speakon connector is
designed for high power loudspeaker use and meets all worldwide safety requirements.
Connections:
The Speakons are wired:
Channel A
Pin +1, Pin - 1 = Output A
Pin +2, Pin - 2 = Output B
Channel B
Pin +1, Pin -1= Output B
The right Speakon, Channel A, has both channel A and B outputs available, so is useful for bridging and bi-amp
operation (see bridged mono operation on page 7). The left Speakon, Channel B, carries only the channel B
All material © 2007. Martin Audio Ltd. Subject to change without notice.
