silvrr
100+ Head-Fier
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- Apr 28, 2013
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There are multiple double blind tests (done at audio meets by a DAC designer) demonstrating sound quality improvements from using higher powered PCs (actually Macs) as compared to lower powered ones (meaning faster processor, etc. not power supply rating).
The tests do not indicate the actual source of the improvement, merely that a higher percentage of resource utilization decreases the sound quality.
So, at first glance, that would indicate a Raspberry Pi would be the wrong direction for high end audio.
But, it's possible that the design of the Pi board happens to remove the cause of the original problem, whatever it is.
So, it would be interesting if someone could compare the sound quality of their Pi to a more powerful conventional PC.
I would be intrested in seeing the setup of that test. From computer to computer things change greatly with the parts used. Even generations of the same Mac (ie mini, pro, etc.) would likely have differences in the power supply and other parts. The only way I could see testing this is to have the same computer and swap the processor out for a higher powered one each time, keeping all other parts and software exactly the same.
I use a Pi as my music player and watching the processor utilization even when playing higher bitrate files (24/192) the processor has a short spike (maybe a second) in the 20-30% range on a single core and then that core sits at 5-7% as the file plays. Memory is only 1GB on my PI and usually ~20% is being used. Im guessing the spike in the beginning is the buffer loading but even 1 of 4 cores hitting 20-30% is hardly stressing the system, I don't see how music playback would require any sort of real processing power.
For those who were interested, I got my Pi 2, Digi+ (transformer version), case, and coax cable today. After some trial and error, I got it set up with Rune Audio. My system is now as follows:
USB Western Digital Passport hard drive connected to powered USB 2.0 hub->Raspberry Pi 2 with i2s Hifiberry Digi+ board->Schiit Bifrost Multibit via coax->Vali 2 with Siemens E288C NOS tube via PYST RCA cables->Dyanamat modded HD600 headphones with SurfCables balanced cables and balanced to single ended adapter.
Prior to this, my chain was the same except I was using a mid-2013 Macbook Air to feed the Bimby via USB, without a Wyrd or Regen.
Using this new setup, which cost a little over $100 for the Pi, board, case, and coax cable, I can tell that the background is much quieter. Pretty darn black all told. This allows me to hear little details that the Macbook obscured, like the needle touching the groove on vinyl rips I have. This setup also has more dimensionality and better instrument separation. It's very easy for me to identify each element within a track now. The Bimby is already very good at this, and the SPDIF connection has made that aspect even more pronounced. The low end also feels tighter, so while it had heft before, now it also has more definition.
While I can't speak to the Mac Mini setup that Mike discussed earlier in the thread, since I haven't heard it, this Pi2 combo is hard to beat for a little over $100 US. If anyone is even curious, I suggest giving it a try. It's an inexpensive and relatively easy way to get away from USB, and avoid all the decrapifiers, reclockers, and expensive USB->SPDIF converters.
I had a similar conclusion when I got my Pi setup. Although I am running off of USB through a Modi, the background is much quieter compared to my desktop and laptop. The hiss I can hear at with the volume cranked on my magni, and no songs playing, is gone when plugged into the Pi.
If you wouldn't mind I would appreciate your impressions in this thread.
http://www.head-fi.org/t/795895/a-70-bit-perfect-audio-player
You had the Pi plugged into the NAS via ethernet, or you had your Pi plugged into your router via ethernet and wirelessly streamed music from your NAS?
Some people are reporting that using the ethernet connection produces some noise compared to using a USB dongle for an internet connection. May not be an issue if using a GPIO output solution as your not sharing the but between USB to send music to the DAC and the ethernet to receive the music. Would be interested to see what people are hearing.