On Thu, 10 Sep 2009 12:24:00 +0100, "Keith G"
wrote:


"Don Pearce" wrote in message
news:4aa8db1e.1466875@localhost...
On Thu, 10 Sep 2009 11:53:17 +0100, "Keith G"
wrote:


"Don Pearce" wrote


Any deck that supports the record on six points can never be described
as "right". It is a ridiculous thing to do. The record must sag
between the points


This is a joke - right?


Of course not. How could a flexible plastic record not sag between
those suspension points?


Stiffness.

Hold an LP up balanced on two fingers at opposite edges - you will see
how much it sags quite easily. Obviously it doesn't sag as much as
that with six suspension points, but it sags much more than enough to
generate a huge signal.

Remember that we are talking thousandths of
an inch to create a big signal, not a sag like a row of bunting. A
record needs to be supported over its whole surface, as flat as
possible.


And yet they are so often not, for one reason or another - without any truly
discernable effect on the sound....


You won't hear it, because the frequency is too low, but what it does
is create a huge subsonic signal that the preamp has to cope with.
That eats into the overload margin, and can result in premature onset
of distortion with loud bass notes. So as a piece of engineering, it
is ****. Some may consider it pretty, but I'm not among them because I
can't separate form from function that easily. If I can see why it is
bad, it will not please me aesthetically.

d