Input impedance for linked channel inputs, Channel outputs – Meyer Sound MM-10 User Manual
Page 17
MM-10 OPERATING INSTRUCTIONS
17
Routing Two Inputs to Four Outputs Each
To route two Channel Inputs to four Channel Outputs each:
1. Set the Link 4 switch to OFF and all other Link switches
to ON.
Routing Eight Inputs to Eight Separate Outputs
To route eight Channel Inputs to eight separate Channel
Outputs:
■
Set all Link switches to OFF.
Input Impedance for Linked Channel Inputs
When a Link switch is enabled, the Channel Input’s unbuf-
fered source signal is transmitted in parallel to each linked
Channel Output. This causes the Channel Input’s imped-
ance (normally 10 kOhms for one MM-10XP) to be reduced
for each linked output. For example:
■
1 Channel Output, 10 kOhm input impedance
■
2 Channel Outputs, 5 kOhm input impedance
■
4 Channel Outputs, 2500 ohms input impedance
■
8 Channel Outputs, 1250 ohms input impedance
To avoid distortion when linking Channel Inputs, make sure
the source device can drive the total load impedance of the
linked MM-10XP subwoofers. The source device must be
capable of delivering a minimum of 16 dBV (6.3 V rms into
600 ohms) to yield the maximum peak SPL over the operat-
ing bandwidth of the subwoofer.
NOTE:
Most source devices are capable of
driving loads no smaller than 10 times their
output impedance. To drive eight MM-10XPs linked
from a single Channel Input, the source device should
have an output impedance of approximately
100 ohms or less.
Channel Outputs
The MPS-488HP’s eight Channel Outputs deliver DC power
(48 V DC) and balanced audio to up to eight MM-10XPs. The
channel outputs can be equipped with either Phoenix 5-pin
male connectors (on the MPS-488HPp model) or EN3 5-pin
male connectors (on the MPS-488HPe model).
NOTE:
For information on MM-10XP cable
requirements, see “MM-10XP Current Draw
and Cable Requirements” on page 13. For informa-
tion on cables and cable accessories available from
Meyer Sound, see Appendix A, “MM-10 Accesso-
ries.” For information on cable assembly, see
Appendix C, “Phoenix and EN3 Cable Assembly.”
TIP:
A single composite cable (such as Belden
1502) wired for both DC power and balanced
audio can be used to connect MM-10XPs to Channel
Outputs.
CAUTION:
When wiring cable connections for
the MPS-488HP channel outputs, it is
extremely important that each pin in the connector is
wired correctly. Make sure the 48 V DC from the
MPS-488HP is wired directly (and only) to the 48 V
DC pins on the MM-10XP connector, and that the
polarity is observed (negative to negative, positive to
positive) to avoid damage to the subwoofer. In addi-
tion, make sure the audio pins are wired correctly;
polarity reversals for audio signals will affect system
performance.
Link 1
Link 2
Link 3
Link 4
Link 5
Link 6
Link 7
On
On
On
Off
On
On
On
Link 1
Link 2
Link 3
Link 4
Link 5
Link 6
Link 7
Off
Off
Off
Off
Off
Off
Off
1
2
3
1
1
5
5
4
5
6
7
8
1
1
5
5
1
2
1
3
5
7
4
5
6
8
3
7
2
4
6
8
!