Specifications Of Speaker Detection - Pioneer VSX-C301-S Service Manual

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7.1.3 Specifications of Speaker Detection
1. Purposes
Automatic detection of connected speakers and automatic selection of settings appropriate for the detected speakers allow you to easily
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play surround-sound without your making cumbersome speaker settings.
2. Speaker detection method
Automatic detection of connected speakers starts 1120 ms after the power is turned on.
• Detection of the center and surround speakers
The microcomputer sends a detection signal and reads the logic of the response signal to judge whether the speaker is connected or not.
The response signal is read at A/D input, and a voltage of 3 V or more is judged as no speaker connected.
• Detection of the subwoofer
The logic of the signal from the phono jack with a switch is read by the microcomputer to judge whether a speaker is connected or not.
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3. Speaker settings
According to the results of detection, speaker settings are made as shown below.
Rules: The setting for the front speakers depends on whether a subwoofer is connected or not. If a subwoofer is connected, the setting for
the front speakers is "small." Settings for other speakers are "small" or "not connected" depending on the results of detection.
Settings for the rear surround speakers are in effect only when surround speakers are connected.
Results of the Detections
Center SP Surround SP
Connected Connected
Connected Connected
C
Connected Not connected
Connected Not connected Not connected
Not connected Connected
Not connected Connected
Not connected Not connected
Not connected Not connected Not connected
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4 User's settings
More detailed speaker settings can be made in Setup mode. Once the user's settings are made in Setup mode, those settings have priority.
However, if the configuration of connected speakers changes, then the detection results become valid and have priority over the user's
settings until new user's settings are made.
E 5 Detection circuit for the center speaker
Detection of the center speaker
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Sub-woofer Front SP
Connected Small
Not connected Large
Connected Small
Large
Connected Small
Not connected Large
Connected Small
Large
10 kΩ
47 kΩ
mute
POWER AMP (IC3401)
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Speaker Setting
Center SP Surround SP
Small Small
Small Small
Small Not connected
Small Not connected
Not connected Small
Not connected Small
Not connected Not connected
Not connected Not connected
Check signal from microcomputer
Detection signal to microcomputer
Mute
About 8Ω
Satellite speakers may be connected.
VSX-C301-S
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Sub-woofer
ON
OFF
ON
OFF
ON
OFF
ON
OFF
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