|24-bits vs. 16-bits Audio - A Visual Analogy?|
As you know, the "High-Resolution Audio" movement is on. A major cornerstone of this is the belief that in the PCM world, 24-bit audio resolution imparts clear audible benefits (as opposed to the standard 16-bits for CD resolution). Indeed, most decent DACs these days are capable of measuring >16-bit dynamic range. Clearly, a push is being made for the subjective "virtues" of 24-bit audio for your headphones, into your home and into your car. The 8-bits of difference between 16-bits and 24-bits of PCM data provides 48dB of extra dynamic range or 256x the number of values to represent each PCM sample! Fantastic advertising buzz. The 24-bit "container" is certainly capable of significantly higher resolution.
Here's the question... Can you hear the difference? Evidently many people believe the difference is audibly significant.
So, you've tried "crowd funding" (and you're probably at this point still waiting for a product), it's time for another round of "crowd testing", folks! Here's what you do to participate:
1. Download the "24-bit Audio Test.zip" file:
WARNING: The test file is big (a taste of the storage demands for those who have not downloaded high-resolution audio). Approximately 200MB for a total of 6 musical samples at 24/96 lasting less than 12 minutes with fully tagged FLAC lossless compression.
Get the file from my FTP server:
Login = 24bit
Pass = test
Please have patience if the server load is high... Anyone able to help out with this, please drop me a note below!
Alternate download sites:
From Uploaded.net: http://ul.to/fqziwlfs
From FilePost.com: https://filepost.com/files/m5b3em11/24-bit_Audio_Test_(Hi-Res_24-96,_FLAC,_2014).zip/
2. Extract that ZIP to wherever you want for playback (computer folder, music archive, server, etc.)
Located within are 3 musical pieces in 24/96 FLAC, each piece with Sample A or Sample B versions. One of them (A or B) is the 24-bit original and the other contains a dithered 16-bit version which has been converted back to 24/96 so your DAC will basically be playing back the same bit/samplerate when you switch between tracks.
The samples are all classical pieces but with variation in instrumentation, vocals, and dynamics. Realize that it's not easy to find good high-resolution audio where the music is recorded and mixed to the highest standards with known provenance. Classical music as a genre is where some of the best recordings can be found.
Here are the tracks:
2. Vivaldi - Recitative and Aria from Cantata RV 679, "Che giova il sospirar, povero core" (performed by Tone Wik & Barokkanerne) - String orchestra with female vocals. Also DXD-recorded and available as a free download from 2L here. Again, I only extracted 2 minutes from the track. DR14 for this track.
3. Goldberg Variations BWV 988 - Aria (performed by Kimiko Ishizaka) as taken from the freely available Open Goldberg Variations 24/96 release. The recording was done at Teldex Studio in Berlin using the Bösendorfer 290 Imperial CEUS concert grand piano. Simple instrumentation for those who love and appreciate the sound of the piano. It's also a much slower piece which provides an opportunity to listen to the decay quality. Low-level spatial room acoustics also easily heard on this recording. Measured dynamic range is a reasonable DR12.
I've included the DR printout from foobar to demonstrate that peak and average volumes are identical for Samples A & B for each piece.
** Note that I'm using the samples under the principle of "fair use" for the purpose of education, research and commentary. I have no ties with Industry and have no financial gain by organizing this. As noted above, these tracks were selected based on excellent quality of the recording and I would highly recommend visiting the source links to sample more high-quality audio tracks in the high-resolution delivery formats (the 2L download page also includes DXD, multichannel and DSD samples).
Needless to say, you need to make sure your DAC / computer / streamer / etc. is capable of >16-bit performance!
I have 14 questions (15th optional) - it should not take long to fill out as most are multiple-choice tick boxes. As expected, I want to know whether you think A or B is the 24-bit track. I also want to know if you're guessing or confident - if you spent time listening, make it count by visiting the survey even if you don't think you can tell a difference. A 'negative' report is just as important as a 'positive' one. I also want to get a sense of your age, gender, tiny bit on musical and technical experience. Also, equipment used, and approximate cost of the audio gear. All data is anonymous and I have no access to your IP address (the web site will keep track of what country you're submitting the survey from - let's make this an international effort!).
Enjoy the music... Happy Easter.
UPDATE (April 24, 2014): ~1 week into the test...
Great to see the responses so far! Just with the FTP site, >120 uploads of the file already. I of course do not expect that many responses to the survey yet since there's plenty of time to listen, but I am impressed by the quality of responses so far and the variety of gear people are using. Clearly folks are not using "junk" gear to assess and the majority are spending time listing out for me what they use and subjective impressions. All will be revealed in time of course...
Keep the responses coming!
UPDATE (April 30, 2014):
>50 responses now. Need more for better statistical power; especially in analyzing each test piece. Expanded the advertisement to the Audio Circle "HiRez Music Circle".
May 2, 2014:
Formal invitation extended to WiredState and Steve Hoffman forum.
May 10, 2014:
Invitation to Pink Fish Media forum.
May 17, 2014:
Invitation to Head-Fi forum.