TV/VCR/Stereo Troubleshooting/Sony Audio video control


Model STR D665
If in the Dolby mode only the center speaker is heard and contains all parts of the track, vocal and music.  If in the Stadium or Hall mode only the side (front, rear) speakers are heard with the vocal part of the track barely perceptible.  The vocal is heard in full in the Dolby mode out of the center speaker.

My first reaction is to have you take a look at the settings for the various playback modes and make sure they are all congruent with what you are expecting.  This set has many settings for various combinations all of which to some extent depend on the incoming audio format.

My second suggestion is to take a look at the wiring from the speaker output lugs on the back to the various wires to the loudspeakers.  Especially look for some wire crossed between one speaker pair and another.

If you now certain that all the settings and wiring is definitely in order and still you are getting incorrect results maybe the receiver needs service or troubleshooting.   There is a big IC at the heart of the circuitry that handles all the demodulation and audio playback modes. If it is defective or a component surrounding the circuit it could be the cause of the incorrect decoding processes.

Hope this helps.

PS: The comment you made about the vocal being almost gone could indicate a phase reversal from the audio source or out of phase wiring of the speakers.  Being out of phase can cause cancellation of the center channel information  

TV/VCR/Stereo Troubleshooting

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