Alittle INFO::

For many audiophiles, digitally recorded music on compact discs 
sounds "processed". In contrast, the vinyl playback of music on a 
turntable sounds much more natural and enjoyable compared to digital 
playback systems. Turntables for playing vinyl records have therefore 
recently enjoyed a resurgence in popularity.

The goal of a vinyl playback system is to extract as faithfully as 
possible the signal carved into the grooves of a record by the record 
cutting lathe. If the stylus exactly replicates in three dimensions 
the path of the cutting lathe, then the extracted signal should be an 
exact replica of the one cut in the groove. Unfortunately, it is very 
difficult to set the tone arm and cartridge of the turntable to 
achieve the exact stylus geometry with respect to the record to match 
that of the cutting lathe when the groove was cut. As a result, the 
signal replicated by the stylus as it travels through the groove is 
not identical to the one cut in the groove.

In an attempt to achieve the best sound, the tone arm and cartridge 
are typically adjusted or "tweaked" in an attempt to get the stylus 
to travel through the groove at a geometry as close as possible to 
that of the cutting lathe. One such adjustment is the tracking 
weight, which is the downward force applied by the stylus to the 
record groove. Another adjustment is alignment, which is the 
positioning of the stylus so that it is parallel with the two sides 
of the curved path of the groove. The azimuth adjustment is the 
setting of the cantilever of the cartridge so that it is 
perpendicular to the groove. Skating is the vector force which tends 
to draw the tonearm and cartridge toward the center of the record. 
Unless countered by anti-skating, this force can cause uneven wear on 
the inner walls of the grooves. Many tonearms therefore include one 
or more mechanism to adjust the tracking weight, alignment, azimuth 
and anti-skating respectively.

The Vertical Tracking Angle (VTA), which is defined as the angle of 
the stylus cantilever relative to the record surface, is another 
adjustment that can be made to the tone arm. The purpose of a VTA 
adjustment is to angle the cantilever to match that of the original 
cutting lathe when the record was cut. Most records are cut by a 
cutting lathe at an angle ranging from 20 to 24 degrees. The VTA is 
adjusted by modifying the height of the tone arm relative to record 
surface on the platter. As the height of the arm is increased, the 
VTA is increased. As the height is decreased, the VTA is decreased.

A number of difficulties are associated with the setting of the VTA. 
Foremost, there is no convenient way of knowing what VTA was used 
when a particular record was cut. To complicate the matter further, 
the angle of the cantilever on cartridges may vary from manufacturer 
to manufacturer. Therefore, visibly setting the arm tube of the tone 
arm to be parallel with the record surface does not necessarily 
guarantee the proper or ideal VTA.

Many turntable owners experiment with different settings and settle 
on the VTA that sounds the best for a particular record. Since the 
VTA cutting angle and the thickness of the vinyl may vary from record 
to record, the VTA that sounds good for one record may not 
necessarily sound good for another record. Constant height 
adjustments of the tone arm may therefore be necessary to achieve the 
optimal sound from record to record. These constant adjustments, 
however, are not only bothersome, but they may cause the other 
adjustments mentioned above to become out of their ideal settings. 
Obtaining and maintaining the proper VTA and other tone arm 
adjustments for turntables is therefore very challenging for many 
audiophiles.

A turntable that has a platter that can be vertically positioned so 
that the VTA between the stylus of the cartridge and the record can 
be easily adjusted without tweaking or touching the tone arm is 
therefore needed.


Sal Calaio
sal@expressimoaudio.com