I have a few basic questions about "hiss." I am curious about how hiss is introduced in recording and playback. How can one determine what hiss is in the recording and what is on the record, or generated by the system. I'm not really concerned with eliminating hiss, I'm just curious where it comes from, what causes it, what emphasizes it etc...
Are records always more "hissy" than digital formats of the same recording? I'm defining hiss as being sort of whitish or pinkish noise, as opposed to "hum".
"Hiss" can occur from two sources. Active electronic devices have general noise that is commonly heard as hiss. The better the circuit design, layout and construction, the lower the noise. Better quality parts also will often lower the noise floor.
In analog recording/playback the hiss is generated both by the electronics of the device and the noise of the recording media. As the magnetic particles of the recording tape pass over the record head, the inconsistencies in the magnetic materials which make up the signal create noise that is essentially white noise. The process is repeated in playback. While the noise heard from a phonograph disc is a combination of both the recorded noise and the noise of the stylus being dragged through the vinyl groove, the amount of hiss/noise in most audiophile LP playback systems is determined by the shape of the stylus. Smaller styli with unconventional shapes and profiles sit in the groove in different ways. How accurately the stylus traces the groove will determine how much noise is generated by the random motion of the cartridge/stylus/groove. It is not uncommon for someone to upgrade their stylus to a smaller, more refined profile and find the stylus rides on "new" vinyl. Installing a better tonearm eliminates much of the random motion of a lesser design that would have been heard as hiss. On the otherhand, poorly designed and installed styli/cartridge/tonearms will damage the record by wearing off bits of vinyl. When these portions of the groove are played again, the result is noise generated by the blank bits of vinyl.