transrota turntable
transrotor turntable with the Origin Live dc motor Upgrade
The originally configured transrotor turntable - leonardo 40/25 was supplied
with a slow speed synchronous motor drive, which exhibited sufficient
speed fluctuation to produce significant pitch changes on sustained notes
from brass or woodwind instruments. I measured the frequency variation
using the Cardas test LP and a 6 digit electronic counter attached to
the loudspeaker terminals. By taking a series of 1 second gated measurements
on the 10 KHz frequency tack it was established that the speed variation
in the signal was +/-0.25%. Since this was an unacceptably high so a solution
to the problem was sought.
The original equipment supplier suggested a higher-grade (expensive) transformer
would solve the problem.
Being unhappy with this suggestion and having seen some adverts for Origin
Live DC drives.
I contacted Audio Revelation who quickly arranged to have a trial motor
and drive delivered. Unfortunately due to the pulley ratios on the Transrotor
deck the speed range of the standard control was insufficient to obtain
the correct speed. This, however, was quickly rectified by the supplier
and new modified unit supplied. After a few hours of break in, the speed
was set up by using a small screwdriver to adjust the potentiometer on
the circuit board and a suitable record played. The sound was considerably
cleaner, the definition and resolution were notably improved and of course
the pitch variation problem had disappeared. On using the test record
and frequency counter as before the frequency variation was now found
to be less than 0.07%.
Thanks to Origin Live and Jay at Audio Revelation the problem was solved
and the OL drive is now a permanent part of my system.
The photograph below shows my Transrotor deck with the Origin Live drive motor.
Tom Stirling. 10/1/03
