Originally Posted by Andre Yew
Sorry for not answering your question, but wow/flutter for turntables is exactly the same distortion as jitter for digital. So someone reconcile these things for me:
1. CD has jitter that is at least 8 orders of magnitude (1 with 8 0s) lower than LP.
2. LP is claimed to sound better than CD.
3. Jitter is the (current) bugbear of digital.
So does jitter really matter for sound quality? Going with the simplest explanation, it seems to me that
there are other factors at work for some people's preference for LP.
Hello, I am a new member, and a professional musician. I do have experience with LP's. Not only do I collect them, but I have made some audiophile grade LP's in the last few years.
It is very difficult to compare the sound of LP's and CD's, because they really are two separate systems, two different ways of storing sound.
A phonograph record (modulated groove) is like a hand print--think of pressing your hand in some wet cement. Then make a casting of your hand. The resulting casting will have the characteristics of your hand, but it will depend greatly on how good quality the casting is.
So, when a record is made, sound causes a needle to vibrate and cut a wavy groove. Modern records use a material called lacquer, Thomas Edison used tin foil originally. In fact, if you go to the Henry Ford Museum in Dearborn MI, you can record on one of Edison's machines from the 1880's. You yell into it, and it will play back something that sounds a little bit like your voice.
Record play back is still getting better and better. A lot depends on how well the record was made in the first place, how it was mastered. One of the greatest mastering engineers ever for Records is still active: Stan Ricker www.rickermaster.com
. Stan worked on projects for the Beatles, Pink Floyd, ELO, Clapton, tons of Classical and jazz landmark recordings, etc. He taught me a lot about how the system works.
Basically the better the turntable, the most sounds you going to pick up, and the quality can appreciate DRAMATICALLY. Unfortunately, most people have not heard a very well made analog recording played on a $5000-$20000 turntable.
CD's store an analog sound in sections. It stores one event of sound, then another event of sound and on and on. The data on the disk is read by a laser, which tries to read as best as it can and then then sound is converted back to analog so we can hear it.
The CD is limited very much by how much data you want to put on it. For one thing CD's do not reproduce sounds above approximately 18000 CPS range. Some people say that humans can't hear that high, others claim it really affects the sound. LP's are not limited it that way. Apparently some LP's can store sounds up to 100,000 CPS!
The technology for CD's dates back to late 1970's early 1980's computer technology. Even at that time compromises were made with the sampling rate so that affordable machines could be made to play them back. Really, the resolution for CD's could have been much better, but the industry did not want to adopt higher quality systems. Only more recently have there been high resolution digital disc systems such as HDCD and DVD audio. These systems sound very nice and represent what the regular CD could/should have offered all along. The public has not embraced the high res. digital discs much, actually LP's do a much better business.
So on to the idea of "jitter."
Problems with speed consistency on a record will result in just what you might expect. A record that moves too slow will sound too low in pitch, and one that goes too fast will sound too high. This was a significant problem for about the first 60 years of the phonograph record. Early record players almost always had variable speed controls to compensate for speed and tracking fluctuations. There were other problems. The mechanical record players were prone to wild fluctuations in speed, and to top it off, most of the early records actually were recorded at different speeds as the needle got closer and closer to the center.
By the 60's turntable and records got much better. Modern high-end turntables can be incredibly really rock solid in terms of consistency. If the record is made right, the pitch and the timing will be quite good.
Regarding CD jitter, to quote wikipedia, "In the context of digital audio extraction from Compact Discs, seek jitter causes extracted audio samples to be doubled-up or skipped entirely if the Compact Disc drive re-seeks. "
Basically when the laser doesn't read data correctly on the CD's surface, a moment of recorded sound is not being picked up. So the CD player has to make up something to compensate for the missing or duplicated data. If it can't effectively make something up, the CD "skips"
Lower jitter for CD implies you are getting more of the correct original data.
quoting Andre Yew.
"LP is claimed to sound better than CD."
I've made recordings and heard them played back on CD and LP. LP wins hands down, at least to my ears.