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Roon - Clipping and streaming

As some may know, upsampling may cause clipping. The explanation is complicated but it has to do with the arc of the new upsampled line crossing above the maximum digital value.

Had an interesting situation last night listening to Jasscast.CA.  Their signal is a little bassy.  On my Squeezebox sound was fine but on my main system ( Roon --> Mytek Brooklyn) I could hear distortion. 

To make a long story short, the upsampling is not identical on these two DAC's due to Squeezebox only accepting 24 bits vs. 32 for the Brooklyn and the Roon signal quality light showed it was clipping on my Mytek.  Easy enough to fix, go into Headroom Management and increase the headroom from -3 to -6. Problem solved, but what a weird thing.  Needed to be Jazzcast, perhaps because their signal adds some bass to the signal? Not sure why, but none of my other sources have ever shown this. 
erik_squires
erik_squires OP
16,144 posts
 
Hey Mapman,

If your device upsamples, then it should apply the necessary headroom management.  There's a great article somewhere in the BenchmarkMedia.com blog, and as they point out, not all older DACs would do this accurately.

In the case of Roon, the Roon software is doing the upscaling (48k/24 to 96k/32), and it is in this process that clipping can occur.  What's odd is that we, the users are being asked to set the headroom for it to not happen. 
gdnrbob
4,449 posts
 
@erik_squires ,
Where in Roon do you set the headroom?
I just looked and can't find that setting.
Bob
jayrossi13's avatar
jayrossi13
188 posts
 
@gdnrbob

When you’re in Roon, right click on the icon of your source in the lower right hand corner. Once you’ve done that you will see an option for DSP.

After you’ve clicked on DSP, you’ll come to a screen where you’ll see headroom management and upsampling as options. You can also access additional DSP features by clicking on add a filter.

As a frame of reference, I'm using the Roon amp on a Mac--so what you see could be a little bit different based upon how you're accessing Roon. 
mapman's avatar
mapman
22,311 posts
 
Hmmm well one reason to be glad I have not jumped to Roon yet.

I’m pretty sure nothing I use up-samples. Not something I would even want at least with CD resolution material. I’d be more receptive if lower and done well. Just do it right please and don’t expect the user to adjust for a defect in design or implementation.

I have a technical background in image processing. The kind they use these days to analyze images from Mars, etc. I don’t want my audio gear doing some of the things to the digital audio data that they do to extract certain information of interest at the moment out of those images often at the cost of other information present originally. Just deliver all that’s provided accurately and use the full dynamic range available without clipping anything please. if anything else is needed it can be done optionally downstream from there.
erik_squires OP
16,144 posts
 
Roon doesn't force you to upsample, @mapman but it is a nice feature to have.
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