Turntable Pre-Echo Sound....?

Eldafort says, "You can only hear pre-echo during a silent groove, but it actually goes on throughout the LP, and constitutes a form of distortion".

Hello, are you sure about this? I have a number of LPs with pre echo. I have never thought about this possibilty.
I must say though that I have never heard any detriment to the sound except for the pre echo. I guess my question would be; are you sure that it continues throught the record or is it lmited to certain areas on the LP? I will listen with this in mind the next time I listen to an LP with pre echo. Certain aberrations on LPs auch as rumble, distortion, groove or vinyl noise can be transient, is pre echo?
Bob

The post-echo and pre-echo occur mostly with loud passages succeeding or preceding quiet ones. When adjacent grooves are about equally modulated, the echo is masked. When levels are moderate, the effect does not occur. Also, good mastering reduces the effect. The idea is to space the grooves wider during loud passages. You can examine a classical LP and see this.

are you sure that it continues throught the record or is it lmited to certain areas on the LP?

Yes it must do. It is a physical limitation of the way LP's are cut. LP = Long Play = some compromises are naturally required to get that extra music compressed (the RIAA curve etc)...this is analagous to good MP3 algorithms that make careful choices to get a compressed audio file that is often (but not always) indistingushable from the uncompressed version.

However, the audibility of this noise (I think of it it as a higher noise floor rather than distortion) will depend on an almost endless number of factors; loud passages close to soft ones, how many minutes of music is on the LP and how close the grooves are cut, the dynamic range of the music itself (more dynamic range will make the cutting of the master more tricky), the outside of the LP or the inner part of the LP... you can go on and on.

In general pre-echo is rarely a problem and even at the start or a track (the worst scenario) it is barely noticeable on the vast majority of LP's.

Fortunately those making the LP are well aware of these issues and will adjust the cutting paramters and choice of where to place tracks such that the LP sounds best (loudest tracks often on the outside).

Shadorne...I agree that "higher noise floor" is a better description than "distortion". It can and is controlled by cutting technique to a level which is inaudible except during silent grooves. I doubt that anyone tries to make it better than inaudible because that would unacceptably limit playing time. But audiophiles like to worry about imperfections that are inaudible, and sometimes nonexistant. Pre-echo does actually exist.

I agree with UC -mostly- on this one, although working with mastering LPs, I find that pre-echo is actually a tape phenomena rather than LP. It indicates that the tape was stored before the LP was mastered- not a good idea as the energy of the tape goes down even over a short time. It also indicates a thinner tape, possibly wound a bit too tight on the reel.

All are issues that are easily dealt with given a little care- but since when have major labels been all that careful? They jumped on digital for the sole reason of cost- cutting the cost of the master tape- now look at the mess they are in!