[mgalusha]

I had a friend with a Zero 100, it was a cool idea but didn't seem to work very well in practice. Probably all the extra friction and the lack of rigidity.

It used a pantograph arrangement I believe it was called.  (sorry to be slightly off topic)

[doug s.]

i recently purchased one of these, used:


the idea behind it is that the headshell swivels to always insure zero-degrees tracking error.  well, this one doesn't work at all; it seems to track in whichever angle you first set the stylus down on the record.  taking it apart, it seems the bearings were buggered up; i reserve final judgment until i get replacement bearings installed.  i know art dudley & ian white like this arm...
http://www.enjoythemusic.com/magazine/equipment/0701/rslabs.htm

doug s.

[WerTicus]

my Garrad 6.400 sounds noticably worse on the last few songs.

I thought it was 'obviously' because the record spins faster at the outside than the inside???

[mmakshak]

Technically, the last track should sound worse.  The thing is, you have to set the anti-skate by ear.  I'm sure if you do, the problem will lessen-to the point where it isn't a problem.  Right now, that means that you have to slightly increase the anti-skate.  Then listen.  The problem is that most people will only listen to that last track.  Listen to the whole album.

[Kulamata]

There are multiple issues here.  

One is that the inner grooves' linear speed is least, so the high frequencies have to be "squished" (the wiggles are shorter, or compressed) for the same frequency.  That's inherent, and why some superdiscs were cut at 45 rpm, and/or have less music and end well out from the spindle.

Another is that a pivoted arm, as mentioned above, is exactly tangent to the groove in only two places.  Different protractors may place the two at different spots; arguments have raged over this one, but it seems to make sense that the inner tangent point should be a bit closer to the center than 2/3 of the way in.  Arm length changes the steepness of the arc, and therefore the amount of the error away from the tangent points. Again, as pointed out above, if the error sounds severe, your cartridge may be misaligned.  Worth checking to be sure your cantilever is not bent, or if the cartridge suspension is tired, that the cantilever is not off center. And for that matter, making sure the cartridge is not canted to one side.

And again, as mentioned above, skating forces vary across the record, and with level; so adjusting by ear is a good way to go.

If you are tracking a bit lightly the problems above can be made worse.  Many cartridges are a tad optimistic about tracking, and do best at the top of their recommended tracking force range.

I recently went from an Eminent Technology II arm to a stock Scout and  do not find the inner grooves objectionable.  Yes, a difference, but less than other differences.

edit: saw a post below that reminded me; is your turntable perfectly level?

[Russell Dawkins]

I think the biggest factor is groove speed. The "wiggles" of the groove have to be .43 times as short (along the groove) on the inner groove as on the outer groove. I just did some elemental number crunching and came up with this:
The radius of the innermost playing groove is 2 1/2"; the outermost, 5 3/4". This gives a circumference of 15.707" and 36.128", respectively. This translates to a groove speed, i.e., the speed past the stylus, (roughly analogous to tape speed in its implications) of 8.726 inches per second on the inner grooves and 20.07 ips for the outer grooves at 33 1/3 rpm, or 11.78 ips and 27.09 ips at 45 rpm.
That's a pretty large difference. The smaller scale of the wiggles near the center, coupled with less-than-optimum tracking angle makes it hard for the stylus to do a clean job. The whole scheme is heavily compromised near the run out grooves, which is why, in the old days of 16" transcription discs for radio shows, apparently they were often cut from the outside in on the first part and then from the inside out for the second part, then outside in, etc., so the listener was not aware of a suddenly changing audio quality!
Russell