Audio Quality: Sample Rates, Bit-Depth, Human Physiology & The Golden Ears

studera800.jpgThere is a curious interface between science and the senses. Perception is often wrapped in psychological or emotional elements. This comes in many forms. It can be a group trying to share their impression of the taste of a particular wine. It can be people listening to music. Every persons experience of such things, being filtered by all that is us, both physically and mentally, is unique.

In a recent post I referred to a silly trend in very high sample rate music. This has been promoted by a variety of people, including HD Tracks, a music reseller that promises to provide “audiophile grade high-resolution recordings.” This term they use to generally describe digital recording a structure beyond the 44.1 KHz sampling and 16 bit linear word length defined by the CD format. They offer music at up to 24 bits and 192 KHz sample rate.

I’ve come to regard this trend as having very little merit. I came to this conclusion after many years dealing with digital audio production, after some experimentation and a lot of research. Like everything else on this site, I don’t profess to be any kind of expert, but I am happy to share my experience.

However,  before I do that let me be certain that it’s necessary. In this particular case I share a view very similar to Monty Montgomery from Xiph.org. Monty presented the case against 24/192 downloads about a year ago in a very thoughtful and well constructed blog post. More recently he augmented that presentation with a great video and a wiki covering the realities of basic digital signal processing. He’s done a fantastic job of presenting the material. Highly recommended. It’s well worth your time.

The analog tape recorder pictured above is a 24-track Studer A824. It was the state of the art in 24 track 2” tape recorders when I was in school. It was a fine piece of engineering and a pleasure to use, but it could not deliver audio as good as the Red Book CD standard.