Thus far I’ve received 83 responses to the HD-Audio challenge — a pretty good number for a casual survey. I spent a couple of hours going through them and created a spreadsheet. Please keep in mind that I’m not a statistician and am ill-equipped to do any fancy data analysis on the responses. But it is obvious to me that some questions can be tentatively answered.
Here’s a few:
1. How many people got 6 correct? 2
2. How many people got 5 correct? 10
3. How many people got 4 correct? 13
4. How many people got 3 correct? 13
5. How many people got 2 correct? 18
6. How many people got 1 correct? 6
7. How many people got 0 correct or couldn’t tell any difference? 17
I did receive a number of comments/emails after posting the results. As I expected, some people blame me for their inability to pick the high-resolution option. Here’s my favorite:
“Just listened to the tracks and wanted to share some thoughts…
All the files are 24/96. Did you downconvert to 44.1/16 and then upconvert? Seems like it would have been a more valid test to rip a CD with EAC and then compare to a 24/96 version. Or download the different resolution files from a commercial service. Less of a chance for conversion artifacts to be introduced into the files. What was the source of the original 24/96 files? There wasn’t anything in the metadata to indicate their source (HDtracks, etc). Hopefully not ripped from vinyl and then resampled.
As you know the quality of the original recording and mastering ultimately determines the potential fidelity of the sound in any file format. I listen to a lot of music in DSD format (and 24/96-192 PCM) and none of the recordings in your test were as good as the best engineered music available today (both analog masters from the 60’s and 70’s and current digital masters (sans compression). They all lacked the depth, presence (soundstage) and detail available in the best engineered recordings. If you don’t start with high quality masters then any comparison is specious.
Thanks for creating the challenge, my suggestions for the next time you do this is to compare DSD versions with a direct CD rip (or redbook audio file from the source) using high fidelity mastered content (e.g. 2xHD). I’ve done this comparison, the difference in the sound quality (detail, soundstage/presence and depth) is amazing.
p.s. I got 5 of the 6 comparisons wrong so there’s something in the way you’ve created and resampled the files (in addition to the mediocre fidelity of the original masters) that is introducing variability in the responses. I noticed that some of these were 5 years old and edited with Audition.”
“Thanks for participating. These files came from my award-winning catalog of native 96 kHz/24-bit PCM masters. As I explained in the original blog post, my original master files were downconverted from 96/24 to CD res and then placed in a 96/24 container to make the file sizes the same. Using content downloaded from a commercial download site is always problematic because virtually all of the files do not exhibit better than CD fidelity. The methodology used in this survey guaranteed both files have the same provenance. The only difference between the original and CD version is the sample rate and the word length. This makes this a uniquely valid comparison.
The sound or “fidelity” of the music you enjoy may be preferable to your ears through your system but the actual fidelity is likely very limited. The heavy use of compression and tweaking of EQ (things that I don’t do) create the usual commercial sound, which lacks dynamics and extended frequency response. What you describe as lacking “depth, presence and detail” are actually attributes that make these recordings exceptional—and real high-resolution masters. You obviously have different listening tastes than those that cherish my tracks. AIX Recordings have won numerous awards and glowing reviews for almost two decades. I acknowledge that they do have a very different sound than most releases.
There would be too many problems using a DSD master and a ripped CD…they don’t come through the same production processes. I’m not a fan of DSD nor 2xHD recordings. What you hear is something other than the difference in resolution. It should be somewhat telling that you were unable to perceive a difference between the same master in its original resolution and in CD spec. I created the catalog over the past 18 years…all were done with the same equipment, resolution, and mixed in the same room.
Thanks for your comments.
PS It turns out that very few (less than 5 out of 100) people that took the survey were able to identify 6 out of 6. Many responded that they couldn’t perceive any differences. Like you, I was hoping that using high-resolution would be perceptible.
I’ll talk about the ramifications and some additional details in a future post.