Al Kooper 5.1 SACD tickles CD-4 demodulator!

QuadraphonicQuad

Help Support QuadraphonicQuad:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Q-Eight

2K Club - QQ Super Nova
Since 2002/2003
Joined
Sep 30, 2003
Messages
3,699
Location
Castlegar, BC, Canada
Playing Al Koopers' SACD version of Supersession through an older Pioneer DV-45A Elite Player plugged into my Sansui QRX-7001. I'm on track 5 "Really" and it's making the CD-4 Radar light on the Sansui light up. It's something in the front channels perhaps as if I put the fader all the way to the rears, the light goes out. If I take it out of AUX mode, the light goes out. If I turn the Carrier Level knob down, the light begins to flicker, then go out. If I turn the treble down in the front channels..... the light goes out.
Al Kooper 002.JPG
Al Kooper 004.JPG
 
I could say something about the nature of SACD creating ultrasonic noise.
More interesting is some 12" 45 records light up the CD-4 light. Spooked me the first time I saw it, thought I had a hidden CD4.
 
Just needs enough 30kHz to trigger
That's exactly what I was thinking. The SACD has the dynamic range to capture that kind of audio. There must just be some stray noise up that high that's triggering the CD-4 Detector. It happens on all songs on the disc, but I found I also had to have the Loudness button pushed in as well.
 
That's exactly what I was thinking. The SACD has the dynamic range to capture that kind of audio. There must just be some stray noise up that high that's triggering the CD-4 Detector. It happens on all songs on the disc, but I found I also had to have the Loudness button pushed in as well.
The stray noise at 30kHz could be from the Noise Shaping Digital Signal Processing thats done to convert from DSD to audio in your player, it shifts the quantisation noise up to High Frequencies. The CD4 decode circuitry in your amp will sit before any band limiting filters in your amp/decoder, so it will see any HF signal at 30kHz.
 
I have one or two 12 inch versions of stereo singles from the early 90s that will trigger the CD-4 light on my Marantz demodulator with automatic CD-4 detection. I always figured it was a harmonic being picked up.
 
Back
Top