High sample rates: Can you tell the difference? UPDATED!

In the spirit of my analogue vs. digital article, it is time for another Mythbusters style debunking session. Today we are going to explore the common misconception that higher sample rates equate to better sounding audio. There is no shortage of rhetoric by self-proclaimed internet experts that by simple matter of dropping a faster processor into a digital unit that you’ll get better sound. This, they claim, is due to having the horsepower to run at higher sample rates. These experts believe that higher sample rates will give better sound with no tweaking of the underlying algorithms. Is it true (and does it matter to the home recording studio owner)?

Testing audio sample rate

My test includes three different audio tracks processed with the same plugin at four different sample rates. The input for each track is an analogue signal recorded at each tested sample rate. The input tracks are then processed at each target sample rate with the Gearbox Plugin from Line 6. Processed tracks are then rendered to variable bit rate mp3 files at 16-bit/44.1k audio. My VBR settings are a minimum of 128kbps to a maximum of 320kbps. Why are the sound samples rendered to the common 44.1k sample rate? Because there is not a single major audio distribution channel available today (or in the forseeable future) that does not require you to supply audio at this resolution. From physical compact discs to iTunes, 16-bit/44.1k audio is the order of the day. The VBR mp3 files I provide as sound samples are even of better fidelity than what you get on iTunes. Also, it doesn’t matter how great things sound in your home studio. The only thing that matters is how great it sounds once your audience is able to listen. When that audience listens, it is going to be at 16-bit/44.1k. A large part of the high sample rate myth is the claim that you should record at high sample rates even though you will downsample to 44.1k at the end. Experts abroad claim this is because you will retain definition through the whole process that will lead to an audible improvement of fidelity after the downsampling.

The sound samples

Here are the sound samples. I have provided sound samples of vocals, rhythm guitar, and lead guitar. Each of the three test tracks is processed at each of the four target sample rates. The sound samples are labeled as a, b, c, d, but are not in any particular order (in other words, a is not necessarily the lowest sample rate and d is not necessarily the highest). All three samples use the same ordering of sample rates though (so if you think c is the 192k sample rate on vocals, then c is also the 192k sample rate on the two guitars).

Your task is to listen to the sound clips and decide for yourself which clip goes with which sample rate or if you can even tell the difference. Decide for yourself. Post here or email me at [email protected] with your guesses. I will wait until I have 1000 responses before I post the results. I fully expect there will be no clear ability to determine which clips were processed at a high sample rate. The real winner will be you, armed with your own informed decision about how important a higher sample rate is to you for your own home recording studio.

Update

I have had 19% of the responses I am hoping to get on this. No one has yet been able to tell which used the “higher quality” algorithms. About half of you have missed the point entirely. Here are some clarifications and additional background on the argument.

• Experts claim that no matter what your final media, recording/mixing at a higher sample rate will result in higher quality final product. Thus, according to the argument, using mp3 as a test is appropriate as it is nearly the most listened to format in our modern world, from iPod to internet downloads.
• Faced with this article, a few of our experts have begun to backpedal. Now they claim mp3 is not a fair test. Fine. I have added full bandwidth, cd-quality wav files of all samples. If mp3 is the most listened to format, compact disc is certainly a close second. With this extra evidence, I challenge you to see if you can still tell which files used the higher sample rates.
• Experts claim that the listener’s sound system will prevent them from being able to hear the subtle differences. If the listener can not hear the subtle differences in this simple test, what makes one think they will be able to hear the subtle differences when listening to your album on that same system?
• Experts have claimed the need to future proof your work. I have mixed well over a hundred songs for over a dozen artists spanning fifteen years. I have not yet been asked to remix or “futurize” a single one of those songs. If your particular studio work has a high chance of being asked to futurize one of your mixes in ten years, then by all means, do what is necessary to record at higher sample rates.
• Experts have claimed the mixing process will be hampered at cd-quality sample rates because you run the risk of introducing artifacts. This is true when mixing with low quality algorithms. If you are running plugins with extreme audio manipulation effects and low quality algorithms based on sample and hold dsp then this is true. You do run the risk of introducing resampling artifacts. If your plugins are of high quality then they are not running on sample and hold algorithms and have no more chance of introducing artifacts at lower sample rates than they do at higher sample rates.
• Experts have claimed that high sample rates are not as beneficial to single sources as they are to an entire mix. This is not an article about mixing at high sample rates. This is an article about the effect of higher sample rates on dsp algorithms found in plugins. I would love to do an article comparing whole mixes, but I don’t think my home studio computer could handle a 24 track mix at 192kHz right now.

Line 6 Gearbox Plugin This plugin package from Line 6 brings you their modeling technology in a VST/RTAS plugin format. This is the plugin I used for processing the samples on this page. It is blowing out at stupidly good deals right now.