48kHz vs 96kHz: audible?
As a so-called audiophile, it is easy to lose one’s balance within many discussions and end up doubting, or at least questioning, whether that subtlety which one hears is real or imaginary.
Today, while engaged in a pastime, I was playing Holst’s "The Planets" in the background, but not at a low volume. I thought that it didn’t sound right. The strings in particular sounded a little abrasive. I noticed this on "Mars," the first composition, so it didn't take me long to perk up. On closer examination, I noticed that the DAC front panel was reporting 48kHz sample rate. I knew that this version of The Planets is 96kHz. Sure enough, JRiver Media Center (MC) was converting all PCM data (whether higher or lower) to 48kHz upon playback. I fixed the MC settings back so that all PCM rates play back at their native rates (up to the capability of my DAC), and all is well now.
Sometime in the recent past, whether due to an application or OS upgrade (of which there was one a few days ago), the MC sample rate conversion table got corrupted or reverted to a default configuration.
It would seem that I am able to hear the difference between 48kHz and 96kHz, at least under these circumstances. The difference was enough that I noticed it while passively listening (I was focused on drawing; the music was “background”) before I suspected a technical issue.
I wonder whether I could have heard this difference in a formal ABX test session? From my past experience with ABX testing, when the differences between the test objects are subtle, observations could easily have been obfuscated due to mental noise consisting of test anxiety, listening fatigue (to same passage over and over) and tedium. Whereas, in my case above, I noticed the difference when I was relaxed and focusing on something else entirely.
I am interested in thoughtful replies.
@tomcy6 is correct. The reason oversampling gives the impression that it may sound better is not due to the oversampling process itself but due to the fact that at higher sample rates, filter artifacts are pushed to higher frequencies which you cannot hear. If a standard CD player employs very good filters (more expensive to build than oversampling), they would sound just as good. |
There have been multiple suggestions here that Media Center may not be performing the conversion well. That certainly seems a plausible explanation, but my perception of jRiver is that they know what they are doing. However, I'll raise this issue on the jRiver forum and report back here. oldaudiophile: by "background," I am referred to what has my primary attention. I am working at a drafting table with my primary attention directed to what I am working on there. The speakers have been aimed and the subwoofer adjusted for this spot using instrumentation. tomic601: I haven't visited 2L yet but shall soon. |
For those who are interested, here is my update, mostly empirical: After researching the sample rate conversion capability of jRiver Media Center (MC) via query on the jRiver forum and researching related discussions there, I have arrived at a likely evaluation of my experience, from the following possibilities: 1) It has been suggested that the sample rate conversion of MC is substandard. The consensus I have researched does not support this suggestion, and MC users feel that it is very good. By default, SSRC sample rate conversion is enabled, with SoX being an optional method. There is some debate on which method is superior, but the MC publishers recommend SSRC as the default, while providing SoX as a checkbox alternative. There is considerable discussion there about the audible differences between the two, and apparently, there is none, whereas there is allegedly and inaudible measurable difference. But I don't know who measured it and what their capabilities were. I have not been able to find any 3rd-party analysis of a comparison of the two methods. In my case, the default (SSRC) was active, and SoX was not enabled. 2) It has been suggested that digital audio is likely to sound its best when played back at its native rate. That has been my experience with other recordings beyond the scope of this thread, but in this case, the native rate is unknown. I don't know at what rate this digital recording of The Planets was made or mastered, and I don't know whether the rate of the release is at that native rate. HDTracks, from whom the files are downloaded, does not provide this data, and they make no claims to provide products in their native rates. (They "offer what the publisher sends them," they effectively informed me some time ago in response to a different query.) However, in my opinion, this suggestion is certainly plausible. 3) MC sample rate conversion is effective (which seems probable given their history and experience), and I can indeed hear the difference between 96kHz and 48kHz. Whether this is due to the accuracy of the data, or to the digital filters employed for each rate, I cannot say. So, I have concluded, for myself, that the difference is indeed audible, and that difference may be a result of a combination of #2 and/or #3 above. I do not feel compelled to explore other comparisons (other players, other DAC's, SSRC/SoX ABX), so it is possible that I am not a very dedicated audiophile. At this time, I am content to identify and play files at their native rates as best as I can.
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