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strange SACD problem

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Posted on March 11, 2020 at 09:00:42
airheadair
Audiophile

Posts: 369
Location: California
Joined: October 18, 2010
I am having a very strange problem with my system. I wonder if anyone here can figure out what could possibly be going on. I am completely baffled.

Here is the story.

On Monday, some old music friends were coming to dinner, and I wanted to demo a song by Patricia Barber for them. So on Sunday, just to be sure,
and for my own enjoyment, I listened to the disc containing that song, all the way through, using my main system, including the Stax speakers ,
driven by my NYAL OTL3's. The disc is an SACD of Patricia's second album, A Distortion of Love,. which I played through my (fairly new) Marantz SA10.
It sounded, as usual, spectacular. However, the next evening, as soon as I turned on the first song on that disc, using the same setup, there was horrible static,
extremely audible. Since I did not want to spoil the demo, I then switched the demo, playing the same song from my computer, using the application Audirvana,
which streams the music (after fancy processing) to the DAC in the Marantz SA10. It sounded fine, although not as good as the SACD would have.

After the guests left, I did some experimenting. All the songs on that disc, when played from the SACD layer, using the Marantz, exhibit the
static. The static is in both channels. However, when I listen to the same disc and layer through my headphones (through a different
amplifier but the same preamp) it sounds fine. Also, other SACD's, played through the main system with the Stax loudspeakers, sound fine.
I've done a bit of cable swapping, e.g. eliminating the crossover, switching the preamp outputs, and nothing seems to change what is going on.
Whatever I do, that SACD causes static, but only with the Futterman and Stax ESL combination. No other SACD's seem to.

The only thing I can can think of is the following. I have heard that some DSD files, and some SACD players, put out a lot of high frequency
garbage that can cause amplifiers to oscillate. Could this be the problem-perhaps with the OTL amps? But if so, why was there no
problem on Sunday, but then one on Monday? Maybe some sort of parameter in the amps drifted a bit? But the amps are dual
mono, with completely separate chassis, and it seems unlikely that both would have drifted simultaneously.

I have ordered a new copy of that same SACD. It exhibits the same behavior.


Any ideas at all about what could possibly be going on?

I'm not sure which forum this post belongs in. If cross-posting is allowed, I guess I should try also try the planar and hi-rez forums.

 

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I'd try a different SACD player, posted on March 12, 2020 at 13:33:41
Ralph
Manufacturer

Posts: 3890
Location: Minnesota
Joined: April 24, 2002
OTLs can have a lot of bandwidth- it may be that your player has developed a fault that is creating a lot of ultrasonic noise- and that noise in turn is messing somehow with the Futterman amp (on account of its bandwidth) in a way that it doesn't with the headphone amp (assuming it has less bandwidth). Without further information this is all speculation; that is how I see it right now.

 

The Pat Barber was the first mistake. Cole, Cassidy, and Krall cant be far behind. nt, posted on March 14, 2020 at 22:48:56
viridian
Audiophile

Posts: 6021
Location: Portland, Oregon
Joined: May 26, 2005
Contributor
  Since:
February 1, 2012
Nt

 

RE: I'd try a different SACD player, posted on March 15, 2020 at 20:11:14
airheadair
Audiophile

Posts: 369
Location: California
Joined: October 18, 2010
Thanks to everyone who had suggestions about my SACD problem. I remain mystified, after some further investigation.

1. A new copy of the SACD exhibits the same problem. I think this rules out dirt or other contamination.
2. No other SACD that I have tested seems to have the problem.
3. I moved my OPPO 203 from the HT room to the main music system and tried the SACD there.
Same problem. I think this rules out the Marantz.

Perhaps I was wrong that on Sunday the disc was fine. The noise is not noticeable at low levels, but becomes very noticeable as soon as I turn up the volume to realistic levels (which I don't usually do).
My conjecture is that some HF junk on the disc overloads the OTL amps beyond a certain level.
This is consistent with what Ralph has said. I wonder if a ferrite bead inserted in the interconnects would help. However, if the problem remains confined to this disc, (which I dearly love), I probably will not take such a measure, except perhaps as an experiment.

 

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