Ancient AR Turntable with NO anti skate

Norman,

The details are over my head but consider this general view.

When modern records are cut they are not done so with even groove spacing.  Instead the mastering engineer may adjust spacing based upon the dynamics of the music being recorded, along with how much play time is desired to be accommodate on a record side.

So even with playback utilizing a tangental arm, how will the arm be controlled to maintain perfect tangency with variable groove spacing?  It is my understanding that two different methods have been utilized.  I believe most of the arm/table combinations have sensors which read arm position and mechanically move it to maintain the cartridge/stylus perpendicular to the groove.  This means some degree of correction is always in play.  The second method is to allow the stylus to "pull" the arm across the record.  Obviously absolute minimal friction is needed for this to be successful which led to development of air-bearing arms.

Neither of these methods is simple or inexpensive to execute, and thus the emphasis on pivoted arms, being simpler to design and less expensive to produce.

I suspect this is similar to the situation why belt-drive tables became so dominant over direct drive and idler designs. 

Cleeds et al.....   I just wonder how many have really compared the sound of a/s with no a/s and came away with the sound being better with it.  Everyone can decide for themselves but to me it is SO clear that no a/s delivers better sound that it really makes me wonder about those who post on these page.  I'll tell you that the timbre of music doesn't change, but the things that make the system sound better in audiophile terms does.  I have a VPI 3D tonearm with a Winfield cartridge.  Any center presented soloist is much clearly centered with no bleed left or right...a much greater sense of depth, and air is presented without a/s ...and so it goes.  The VPI arms are very easy to add/remove a/s while the record is playing...simply by flipping the device over.  It matters not that posters use a/s or not....it just makes me bewildered that people play by the "rules" and forge ahead.  I should mention that I set up my arm extremely carefully with a 2.6 grm tracking force (manufacturer's spec), use a Fozgometer, and Mint protractor.

Normansizemore.....Do you remember the Harmann-Kardon turntable with linear tracking??

pryso,

There is no question that the reason we see so many belt drive tables is because they are cheap to manufacture.  Idler drive and direct drive tables are definitely more expensive.  I remember looking at my Linn LP12 and Aristion RD11 (same table) and thinking that other then the nice plinths there isn't much to it.  My Garrard, Dual and EMT are truly custom made tables.  Each part manufactured specifically for the table. The build quality is so evident.  I tire of seeing massive acrylic platters, powered by puny little motors that struggle to get up to speed. 

To me (my opinion) that's hardly engineering. 

Norman

stringreen,

Normansizemore.....Do you remember the Harmann-Kardon turntable with linear tracking??

Yes I do.  It was the Harman Kardon ST-7 with the RABCO tonearm.
They had some problems at first, but I have seen those perform quite well. 

I believe that originally, RABCO was an independent company and Harman Kardon eventually bought them out and took over manufacturing.  That is when some of the minor production issues got sorted out.  It was quite popular in the mid seventies.

Norman