nvidia shield - upsampling

[thejck]

I have been struggling to find the answer to this question.
I grew up on windows and have spent a lot of time trying to achieve quality music reproduction with the way windows used to screw up the audio stack and resample 44.1 to 48khz. That used to sound terrible and I was glad when i discovered wasapi and they finally introduced exclusive mode.

I recently picked up a nvidia shield pro and was testing this out using plex and kodi and even a trial version of roon.
I found that it was upsampling everything from 44.1 to 48.
I did some more testing and found
flac 2 channel 24/96 plays and the receiver shows it playing at 96kHz
flac 2 channel 24/192 plays and the receiver shows it playing at 192
flac 5.1 channel 24/96 plays and the receiver shows 5.1 96Khz
flac 2 channel 16/44.1 plays but the receiver up samples this to 48Khz

So my question is. Is upsampling bad if done correctly? if that is even possible and any thoughts on how to check?

 

[CoastingOR]

The upsampling of 16/44.1 to 16/48, coming from my Nvidia Shield 2017, whether done internally in the Shield or by the transcoding done by my DLNA server, is noticebly worse than playing 16/44.1 straight into my DVR via a USB drive or via DLNA without transcoding.

I have read (some time ago and forget where) that Android insists on upsampling to 48KHz or multiples of that because that is what audio accompanying digital video formats has and it's "easier" to make it all the same. It may be easier but not how I want to listen to my 16/44.1 flacs ripped from my original CDs. My Roku Ultra and my Amazon Fire TV 4K do pretty much the same. I can't stand the way the high end of the audio is mangled by the various systems during upsampling so I cannot use their otherwise useful (in some cases) UI. I'm planning to switch to a fanless mini PC feeding audio to my AVR by HDMI or maybe the mini plus a DAC if the HDMI isn't adequate.

 

[Jimbob54]

I have been struggling to find the answer to this question.
I grew up on windows and have spent a lot of time trying to achieve quality music reproduction with the way windows used to screw up the audio stack and resample 44.1 to 48khz. That used to sound terrible and I was glad when i discovered wasapi and they finally introduced exclusive mode.

I recently picked up a nvidia shield pro and was testing this out using plex and kodi and even a trial version of roon.
I found that it was upsampling everything from 44.1 to 48.
I did some more testing and found
flac 2 channel 24/96 plays and the receiver shows it playing at 96kHz
flac 2 channel 24/192 plays and the receiver shows it playing at 192
flac 5.1 channel 24/96 plays and the receiver shows 5.1 96Khz
flac 2 channel 16/44.1 plays but the receiver up samples this to 48Khz

So my question is. Is upsampling bad if done correctly? if that is even possible and any thoughts on how to check?

The OCD part of me hates upsampling that I havent requested. However, the pragmatist in me says its going to make not one blind bit of audible difference. I dont know if it is possible to check if the upsampling is "good" or "bad" but I think bad would have to be very very bad indeed to make a difference.

 

[CoastingOR]

The OCD part of me hates upsampling that I havent requested. However, the pragmatist in me says its going to make not one blind bit of audible difference. I dont know if it is possible to check if the upsampling is "good" or "bad" but I think bad would have to be very very bad indeed to make a difference.

Wrongo. I assume that there can be well-done upsampling that is inaudible. I'm in my 70's and my hearing isn't like it used to be but the difference is very audible. The high end is muffled and I don't hear that far into the high end anymore. It's very clear and unacceptable. Of course the choice of music could mask it for someone. Try it yourself. Some nice jazz. Duke Ellington and Johnny Hodges or Bob Wilber or Miles Davis...Or, Linda Ronstadt's rock or country or torch songs with Nelson Riddle. Straight into the amplifier untouched 16/44.1 or put though Shield TV and turned into 16/48. You will hear it if you hear as "well" as me.

I haven't used any of my audio apps to try to do "good" upsampling because I have no interest in upsampling 100's of GBs of music because of a stupid assumption by engineers who don't care about the audio quality. I did look for players that would bypass the Android/Fire/Roku upsampling and found none that would install straight in without tricking with the OS.

 

[CoastingOR]

So, I have my solution. It may horrify many here. I spent a career building sophisticated electronic instruments to do state of the art electrical measurements from single nerve and muscle cells, so I'm not intimidated by building circuits. However, a raspberry pi combo at a cost close to fanless miniPC's seemed like a choice I could pass up. As I looked, I found a lot of fanless PC's that people liked at $100-140. The more I looked the more I found that a little more money meant a lot more performance. I ended up with a $180 fanless celeron 4 core 4 thread computer. 4GB RAM, 64 GB SSD, Windows 10 Pro license. Surprising power and flexibility

My plan went from getting a dedicated streaming little box and USB DAC, to instead, trying to use the HDMI connection to my AVR's DACs. I knew I could send out non-upsampled 44.1 KHz because my laptop could. I also knew that feeding the AVR's DACs the 44.1KHz CD-quality music sounded way better than the various streaming devices' 48KHz upsampled versions. I got the box and was very impressed. The little book-sized box delivers 4K 60Hz video beautifully. Windows actually seems usable although I'm not a Windows user. I immediately ordered a modest SSD to install Linux on. With Windows, I played music on a USB flash drive with Foobar2000 and it delivered great sounding 44.1KHz, non-upsampled flacs. I'm sure it might not test super highly but it sounds as good as my ears can experience it and way better than the 48KHz upsampled stuff so many apps fed to my streaming devices. When the 500 GB SSD arrived I installed Fedora and tested several players, settling for now on audacious. It works great, no upsampling, no mangling the audio. Now I'm setting up NSF between the little box and my desktop server in my office.

 

[CoastingOR]

So, a correction is in order and perhaps an update. Correction is that Windows interferes with Foobar. Foobar, while playing 44.1KHz content says, "flac 44.1KHz." However, what ends up coming into the AVR via the HDMI cable is 48KHz. Once again the OS fiddles it. I didn't play with it long enough to see if the 48KHz from Windows does a better upsampling job than that from my streaming boxes. Neither did I bother to try to figure out how to trick Windows 10 into leaving the sample rate alone.

I installed Fedora on my new 500 GB SSD and started testing players with the HDMI out to the AVR. Audacious played 44.1KHz through the HDMI just fine. I just didn't like the user interface. I found that all the flacs I wanted to load into the miniPC fit on a bit over half of the drive. The rest of my music was in ogg/vorbis at a high quality setting. I convinced myself easily that I couldn't tell the difference between flac and those ogg files and they were about 30% of the flac size so the whole shebang fit with room to spare on the remaining space on the SSD. Suddenly, I don't have to fool with NFS, DLNA, a server down the hall or a new user interface. I'm using "deadbeef" a Linux player with a strange name but a really nice useable UI: folders with albums of music open as albums. The music sounds great using the DACs internal to my AVR.

The side benefit of this fanless computer is that it is really quite swift, a byproduct of the celeron processor, Linux and SSDs. I get to use it as a computer with the TV as the screen. My wireless keyboard and mouse allow me to copy and edit text which can be picked up by my laptop over ssh. I can use the keyboard to more easily search for content on youtube and then simply view it from the miniPC since it displays very nicely on the TV and it plays video nicely. It doesn't do HDR and the streaming boxes are better for 4K HDR movies with multichannel sound. Nonetheless, I have found that this little fanless miniPC is much more useful than I expected and it's made my music playing simpler the the DLNA server/client and amazingly convenient.

 

[RayDunzl]

So my question is. Is upsampling bad if done correctly?

My DAC says it takes every bit rate it receives and ups the rate to 211kHz internally.

It performs right along with the other better measuring DACs.

I will assume upsampling is not "bad" if done "correctly".

 

[BDWoody]

The OCD part of me hates upsampling that I havent requested. However, the pragmatist in me says its going to make not one blind bit of audible difference. I dont know if it is possible to check if the upsampling is "good" or "bad" but I think bad would have to be very very bad indeed to make a difference.

I've not noticed any kind of difference with either of my Shields... I'm not offended by upsampling, so it's less likely I'd hear a difference.

 

[RayDunzl]

I'm not smart enough to separate what goes on in the DAC chip vs what goes on outside of it, but I don't worry about "bit perfect".

Here's someone with more knowledge of his subject explaining his implementation.

https://benchmarkmedia.com/blogs/application_notes/inside-the-dac2-part-2-digital-processing

I would presume other DAC chips may or may not be comparable inside. R2R ladder DACs, different again, I suppose.

But all with the same target: reproduction of the bandwidth limited analog signal that tickled the ADC.

(the link is four years old and the DAC described one generation behind the current - similar - product)

 

[CoastingOR]

So, a small additional contribution on upsampling. As I said above, I have 3 streaming devices: 1) 2017 version of Nvidia Shield TV; 2) 2020 Roku Ultra; 3) 2020 Amazon Fire TV 4K Stick. All three insist on upsampling 44.1 KHz CD quality audio to 48 KHz before passing it via HDMI to my AVR. I I read that the rationale for this upsampling that was for compatibility with 48KHz audio within videos. Regardless, all three streaming systems's upsampling of CD quality 44.1KHz played by my AVR had an obvious audible distortion of the high end of the audio frequency range audible to my old-guy ears.

I did think about the question of whether upsampling could be done well and not mangle the audio. I upsampled several tracks from 44.1 to 48 KHz using the audio editing software "Audacity." Switching back and forth between the two sample rates I cannot tell the difference between the two sample rates. My tentative conclusion is that Audacity does the upsampling with less added distortion than did the 3 streaming devices. That's not too surprising--it's running in higher speed hardware with sophisticated software and not trying to do it on the fly. So, if you have hardware that does a good job of doing that upsampling you should be fine.

I did not choose to take this information and manually upsample all my music nor did I test my Audacity resampled music directly in the AVR. The solution of my little miniPC sitting on top of my AVR is ridiculously straightforward and far more versatile in many ways than enlisting two computers 3 rooms away from each other and wrestling with clunky UI used by DLNA clients/servers.

 

[TabCam]

All Android devices have the 48/96/192 kHz upsampling problem. It seems real time conversion is time and cpu load constrained which results in a less than ideal conversion. I have the same experience so I opted for a Raspberry Pi headless audio player.

 

[phoenixdogfan]

Wrongo. I assume that there can be well-done upsampling that is inaudible. I'm in my 70's and my hearing isn't like it used to be but the difference is very audible. The high end is muffled and I don't hear that far into the high end anymore. It's very clear and unacceptable. Of course the choice of music could mask it for someone. Try it yourself. Some nice jazz. Duke Ellington and Johnny Hodges or Bob Wilber or Miles Davis...Or, Linda Ronstadt's rock or country or torch songs with Nelson Riddle. Straight into the amplifier untouched 16/44.1 or put though Shield TV and turned into 16/48. You will hear it if you hear as "well" as me.

I haven't used any of my audio apps to try to do "good" upsampling because I have no interest in upsampling 100's of GBs of music because of a stupid assumption by engineers who don't care about the audio quality. I did look for players that would bypass the Android/Fire/Roku upsampling and found none that would install straight in without tricking with the OS.

I just ordered a NVidia shield and it's arriving Sunday. I'll be using it to provide 24 channel Atmos to my Smyth A16 Realizer. Not planning to use it for streaming two channel music. I suppose it will be OK for movies, I hope.

 

[Sancus]

I just ordered a NVidia shield and it's arriving Sunday. I'll be using it to provide 24 channel Atmos to my Smyth A16 Realizer. Not planning to use it for streaming two channel music. I suppose it will be OK for movies, I hope.

Shield doesn't re-sample any of the Dolby or DTS formats, it bitstreams that all directly, assuming device support and that you're using an app that supports that(which is most of the popular ones, afaik).