Origin Live Building a turntable almost from scratch - Manual (Page 24)

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Hi-Fi cartridges - setting up procedures
Introduction
General comments
As we supply most makes of hi-fi cartridge we get asked questions from time to time about various issues regarding set
up and care. To help newcomers to this area we have published the following notes. These guidelines are of a general
nature - we publish them only to be of help and although widely accepted they are not formally authoritative - we cannot
accept liability if you choose to use them and neither do we encourage the time consuming occupation of answering
queries surrounding the procedures outlined - these are best referred to the manufacturer of your specific hi-fi cartridge.
For those new or inexperienced to fitting hi-fi cartridges we would state that this is NOT difficult and much of the detail
and perfectionism outlined below is for those who like to experiment. We ourselves do not normally check azimuth, or
vary tracking forces from the manufacturers recommendations - neither would we worry if the arm was up to 3mm away
from the recommended distance from the spindle - although all these details are audible they are generally of a fairly low
order, although tracking force and VTA are worth trying should you feel anything is lacking. If things seem complicated
we would encourage you not to be put off as it all becomes clear once you get started.
Before fine tuning the set up as described below you should allow the cartridge to "run in" properly - at least 40 hours for
some cartridges.
Importance of cartridge set up
Hi-Fi cartridges travel like a bobsleigh through the grooves of a record only a few thousandths of an inch wide. You hear
groove displacements of the order of a few millionths. (That’s like splitting a hair into one thousand pieces.) Every bit of
motion or vibration allowed at this level can be heard enormously amplified through your speakers. For this reason it is
good to set up the turntable and arm correctly so that the audio cartridge can do it's job properly. For instance a turntable
out of level can produce side forces on the pickup cartridge tip that will wear it more on one side than the other as well
as have a slightly degrading effect on the wear of your records.
Levelness
When a turntable goes out of level, the platter bearing performance and the arm’s dynamics, specifically anti-skate, are
negatively affected. So be sure your turntable platter and tonearm mounting board are level - use a spirit level. If the
platter is out of level, first adjust the surface that the deck stands on. The suspension (in the case of a suspended sub-
chassis design) may also need levelling if it has subsided over time.
Hi-Fi cartridges alignment
Alignment for hi-fi cartridges needs to be optimised in three different planes. However, it cannot be perfect in all three
planes, so it must be optimised for an overall best balance or compromise. The final authority should always be your ears
and preferably over an extended period of listening time. Bear in mind that each record is cut slightly differently. Here
again, optimise for an overall balance of good sound over a wide range of records. The three alignment planes are as
follows. (Please note that it is the stylus, not the cartridge that is being aligned.)
Lateral tracking angle
Viewed from above, the hi-fi cartridges arcing movement across the record must maintain the stylus in the same relation
to the groove as that of the cutting stylus’s straight-line tracking; this is Lateral Tracking Angle, or Tangency. Apart from
linear tracking arms this is always a matter of the best compromise.
Azimuth
Viewed from head on, the stylus must be perpendicular in the groove so as not to favour one groove wall, and therefore
one channel, over the other wall/channel; this is Azimuth.
Vertical tracking angle (VTA)
Viewed from the side, the stylus must sit correctly in the groove, at the same angle as the original cutter; this is Vertical
Tracking/Stylus Rake Angle. VTA, however, varies from record to record. Therefore, this alignment must be set by ear,
even more than is the case with the other adjustments).
Hi-Fi cartridge aligning tools
Tools required are an alignment gauge, a tracking force gauge, a FLAT record, a screwdriver or Allen keys of the right
size (usually 2mm), a good light may also be helpful. Small needle-nose pliers and a magnifying glass all help. It also helps
to have the hi-fi news test record. Treat the arm with care as some parts are fragile. To this end ensure that tightening of
any bolts is carried out gently and without causing undue strain.
Check hi-fi cartridge clip connections and mounting
Tonearm wiring uses a standard color code for left channel (L) and right channel (R) and polarity. Coding is as follows: