Origin Live Enterprise C User Manual
Specific instructions, Dual pivot bearing design – why, Handles like a conventional gimballed arms
Dual pivot bearing design – why?
The Enterprise arm is a performance leader by virtue of it’s
innovative dual pivot bearing on the horizontal axle (which governs
the arms vertical movement). This design is similar in many
respects to uni-pivot designs – low friction and high decoupling
which give excellent defi nition and transparency. However
uni-pivots can be fi ddly to set up and because of their relative
instability exhibit a mediocre bass performance. Dual pivot design
has all the advantages of uni-pivots but none of the drawbacks.
Vertical movement of the arm is handled by the dual pivot and
horizontal movement by our usual highly specifi ed conventional
bearings.
Handles like a conventional gimballed
arms
You should handle the arm in exactly the same way as a
conventional gimballed arm. In other words you do not need
to worry about setting up azimuth and balancing the arm. The
azimuth has already been set, such that the headshell is parallel to
the arm mounting surface. We strongly recommend that you never
adjust the factory setting even though it is possible via the pivot
screws. Correct azimuth setting is tricky at the best of times and
unless an extremely careful record is kept on the original factory
settings the arm will probably end up not working correctly. If
in trouble see technical support on our web site www.originlive.
com/troubleshooting_tonearms.htm
Having said this it is recommended to slacken off the azimuth
clamping screws NOT the azimuth adjuster screws. Slackening
the clamping screws has the effect of increasing the performance
signifi cantly.
Understanding dual pivot
The below illustration shows the dual pivot bearing to give an
understanding of why the horizontal axle is free to move a little in
all directions except downwards. This may be a little disconcerting
until you become confi dent of the inherent virtues delivered in
performance. It is also reassuring to know that the arm cannot be
knocked off it’s bearings or come loose in any
way. You can turn the arm upside down and
nothing will fall off as it would in the case of
a uni-pivot!
The pivot bearings are designed to reduce
friction to the absolute minimum practical
level. In doing this there is a fi ne balance to
achieve both a long lasting, robust design and
realizing the potential of extremely low friction. In practice this
means that the arm must have a slight degree of movement due
to a rounded tungsten point in a shallow radiused (nearly fl at)
sapphire jewelled bearing cup. The alternative to this is a very
sharp, potentially fragile point in a deep v shaped cup – this
would certainly restrain the movement of the point but would also
increase friction.
The pivot points will “self centre” by sliding into the bottom
of the shallow low friction cup. However the fi nal resting place
of the point in the cup may vary by 0.01mm or so. This would
not be noticed without the use of a very accurate digital stylus
force gauge – as the pivot position changes fractionally so can the
tracking force by up to 0.02 grams. In practice this has no effect on
performance and is also common among certain unipivot designs
with very low friction bearings.
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)
PIVOT POINT IN THREADED SCREW
Adjusts azimuth
YOKE RIGIDLY FIXED TO ARM TUBE
TURRET PLATE
- rotates freely on conventional bearings
ENTERPRISE FRONT VIEW OF DUAL
PIVOT ARRANGEMENT
SIDE VIEW OF DUAL PIVOT
ALLEN SCREW HOLDING PIVOT POINT
rotating clockwise raises this side of the yoke.
Movement
NOTE
It is not nessecary to understand
these diagrams but they are
included for information only
SAPPHIRE CUP BEARING
When arm is horizontal - bottom surface
of the yoke should be roughly parrallel
with turret plate in side view.
This is set at factory and only held by
friction fit which can be forced out of
alignment by mishandling or transit.
Cork strips are inserted to prevent
movement occuring in transit.
Specific instructions -