Audiophile grade "low noise" SD-Card?

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You've got to see it to believe it: Sony markets a "low noise" SD-Card specifically targeted at the audiophile community: the SR-64HXA.
Probably aimed at the users of the $1200 ZX2...

This passage:
"...is sure to draw the ire of many a mainstream tech publication and its readers."
caught my eye, and sure enough, it has.

Even though I like good music played through a good sound system, I think Sony has lost credibility here... wouldn't you agree?
 
I agree, there is no noise once we turn the power off. Turn it back on and let's check it out:

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Digital Cables and Noise | AudioStream

Archimago's Musings: MEASUREMENTS: Corning USB 3 Optical Cable, Ground Loops, and Noise.
 
With all due respect, cabling is nothing to do with this subject.

Neither is making extremely dubious claims about class d amps.

But, on topic for a change, I personally can't imagine any remotely plausible case for claiming one sd card better than another for audio, other than versus some (probably imainary) card that is too slow to keep up with the data transfer rate.
 
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But digital is digital. There is no noise. It is either yes or no or 1 & 0!
That is why class D is so good, What goes in comes out, nothing else.

Jon, not wanting to split hairs, but class D is analog amplification. Time, current, voltage. Not numbers. That why you see all the familiar THD and noise issues in class D as well.

Jan
 
I agree, there is no noise once we turn the power off. Turn it back on and let's check it out:

FCG0zC2l.jpg


HBO31rNl.jpg


Digital Cables and Noise | AudioStream

Archimago's Musings: MEASUREMENTS: Corning USB 3 Optical Cable, Ground Loops, and Noise.

Amazingly this problem is often solved by good engineering practice, think how many high rel. products are out there... the best bet is to widen your field and maybe look at Henry Ott, Ralph Morrison audio based white papers are often biased and have a distinct mythological tone.
It is called EMC engineering......
 
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Perhaps you might be missing the point...

Unfortunately this thread is making no distinction between acoustic and electrical noise. If you put your head very close to an SD card while it is writing, you will hear sound.

This is a real problem in the underwater acoustics community, because without special isolation mounting we can see (in the spectrum charts) and hear the sound produced by these cards. The larger the card, we observe, the louder they are.

I haven't opened up one of these cards to see, but if there are ceramic capacitors in the card itself (in addition to the controller and NAND flash dies, that might be the source. I suppose it's also possible that the memory die itself might be weakly piezoelectric, peak power in these chips can run to 350 mW during write cycles so there's definitely enough power to cause this level of acoustic disturbance.

I wound up on this thread because I was looking for an elegant way to acoustically decouple the SD card from the rest of our product.
 
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