Listen SC Amp, User Manual

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14
SC Amp
TM
Manual
Operation
Single Speaker Test Example
When using the SC Amp with a
Balanced In/Out sound card, you
should use balanced cables for the
connections as shown in
Figure 7-2 .
SC Amp accepts standard 1/4” TRS
(tip/ring/sleeve) phone plug
connectors.
If the sound card has only single-
ended (unbalanced) connection
available, you should only use 1/4”
TS (tip/sleeve) connectors.
Note:
Connecting two loudspeakers in parallel to one amplifier output reduces the
impedance of the load, e.g., 8 Ohms in parallel with 8 Ohms equals 4 Ohms.
SC_Amp’s performance will vary with loads below 4 Ohms.
Impedance Measurement
When using SC Amp with SoundCheck, the Impedance Analysis Step
should use the AmpConnect/SC Amp circuit model as shown in
Figure
7-3 .
z
Under Impedance Measurement Method you select
AmpConnect/SC Amp
z
Under Rref you must select Z-Low
Loudspeaker
(DUT)
-
+
Computer
Audio Interface
Input 1
Input 2
Balanced
Output 1
Balanced
Output 2
Reference
Mic
Balanced Cable
Balanced Cable
Output
Figure 7-2: Single Loudspeaker Test
Figure 7-3: Impedance Step