Atlona HD570 distortion / subsonic transients

In my linux pc-based dsp system for crossover and EQ of active loudspeakers, I use a pc to send 6 channels of processed audio over hdmi, with an Atlona AT-HD570 to convert all channels to analog before amplification.  Recently I discovered that this setup can distort badly at moderately high signal levels, in a way that produces large transient subsonic signals which, when amplified, could permanently damage loudspeaker drivers.  My measurements point to a flaw in the HD570.
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Digital Piano Reproduction: Phase Issues 2

Following up on an earlier post, I’ve been investigating why digital pianos sound so bad in stereo.  I did a spectral analysis on the outputs of my Yamaha CP50 stage piano.  The results confirm what I and others have been hearing: because of how they are sampled, stereo pianos don’t reproduce well except in headphones.

Update: based on my investigations here and elsewhere, I’ve designed a new loudspeaker system to deal with the challenges of turning piano samples into naturalistic live piano sound. Visit to purchase or get more info.

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