PCRECORDING.COM - - Resolution Rate
16-bit vs. 24-bit resolution
One of the biggest debates at present is whether recording at 24 bit resolution is sufficiently better to warrant the extra CPU and harddrive load. (See my table on my harddrive page for examples of the load difference the resolution makes.) As many of you probably know, present CD quality audio is recorded at 16-bit resolution with a sample rate of 44.1kHz. Many soundcards these days are capable of recording at 24-bit resolution with a sample rate of 96kHz.
So what's the question you ask? Well, it is part mathematics and part esthetics. Recordings at 16-bit resolution have a theoretical dynamic range of 98dB, whereas 24-bit had a dynamic range of 120 dB. The significance is that the greater your dynamic range is, the lower your noise floor is and the higher your maximums are. The benefit of a higher bit-rate (higher dynamic range) is that your will be able to record very quiet passages without introducing resolution related noise.
Frequency response is determined by the sampling rate your system uses. You can determine the rough frequency response you can expect by halving your sample rate. For instance, "CD quality" recordings are done at 0-44.1 kHz. Half of that is roughly 0-22KHz. A sample rate of 48kHz results in a frequency range of roughly 0-24kHz. The typical frequency range of human hearing is from approximately 20Hz to 20kHz. The issue is then why record at higher sample rates if the human is not going to hear it anyway? For most trained ears, there is an audible difference between 44.1kHz, 48kHz and even 96kHz. The reason is that there are artifacts (due to sampling errors and such) in lower sampling rates that are perceived but not necessarily "heard" by the human ear.
Much of the debate centers on the "quality" of the sound versus the technical specifications one might expect. The quality of the analog to digital converters and digital to analog converters used by the soundcards is a major factor. There are many that would hold that a high-quality 16-bit converter will give you better sound than a low-quality 24-bit converter. They are probably right.
Another factor to consider is what the dynamic range and frequency response of your music will be. For instance, if your are recording an orchestra, the dynamic range and frequency response needs will be high. Therefore, higher sample rates and bit rates are probably appropriate. If you are a Computer/Midi/sequencing type or a metalhead the dynamic range needs are probably low. In this instance, 16-bit/44.1kHz may be all you need.
For a very technical but interesting analysis of this issue please go to Analog.com and read their whitepaper.