Origin Live Aurora MKI - Manual (Page 8)

8
Set the switch on the control box to the first click i.e. 33 rpm setting.
Set P1 so that the platter turns at 33.3rpm. When setting the speed, place the arm on the centre track of a record
so that the cartridge is tracking the grooves this ensures that the drag of the cartridge is taken into account.
Speed variations of up to plus or minus 2% are quite common on decks and the dc motor is capable of plus or
minus 0.1% accuracy. Use the strobe disc provided to set the speed (full instructions are on the card).
However
if you have problems using the strobe card, then count the rpm using the following method. Counting the 33.3
revs per minute is best accomplished by placing a small piece of sticky tape on the perimeter of the platter and
then counting 100 revolutions. 33.3 rpm is exactly 100 revolutions completed in 3 minutes. To save time in
the early stages it is easiest to count 50 revs in 1 minute 30 seconds (or 25 revs in 45 seconds) and save the 100
count for the final check.
Please note the following points when setting the speed. Firstly all the figures below are based on setting the
speed on the deck using the centre track and letting the deck play for a good 5 minutes beforehand with the
stylus on the record so that the whole system has settled down. The regulators seem to take about 5 minutes to
warm up,
so speed is about 2mins 58 seconds for 100 revolutions when the system starts from cold. In o ther
words it is 2/180 x 100 = 1 % fast when started from cold. Speed variation with the dc motor varies minutely
depending on the track played and cut of record.
Click the rotary switch to the 2nd click clockwise and set P2 so that the platter rotates at 45 or 78 rpm (if you
wish) using the same procedure as outlined above.
The dc motors are noisy to begin with and are never completely silent in comparison to a/c motors. This is
thought to be due to a different type of precious metal brush. Having said this they still sound a great deal better
in performance terms. To assist "running in" you can turn the speed right up via the control box. The motor
then runs at high speed. Allow this for approx 4 hours. After the running in period reset the motor speed. The
motor should then be run for approx 3 days under load (i.e. turning the platter) to free it up from vibration and
to “bed in” the bearings.
Like most turntable manufacturers we recommend that you leave the turntable running between changing
records as this reduces the belt wear that occurs with constant stopping and starting.
N O T E S O N M O T O R & S P E E D S E T T I N G
-Do not use the power supply for anything other than the dc motor or the power supply will definitely be
irreparably damaged and you could also damage the equipment you are plugging it into.
-The circuit will take around 8 hours to run in and sound it's best.
The speed stability of your deck should be excellent once everything has settled down in a listening session i.e..
The power supply and switch b ox have been left plugged in on standby for 15 minutes, the platter has been
turning for 2 minutes and the cartridge has been on the record for 30 seconds. Bear in mind that the ear detects
when music is playing slightly slow much more easily than it detects it playing fast. For this reason most
manufacturers set their decks to run slightly fast. You can expect a bit of speed variation when the motor is first
switched on - it takes about 2 minutes to warm up properly and then the motor should run at it's correct speed
but only when the stylus is on the record. It is highly preferable to keep the transformer plugged in at all times
(unless you are away on holiday) because it takes a good 15 minutes to warm up from cold and run correctly.
When in standby mode the control box draws a negligible current so you needn’t worry about your electricity
bill.
If you keep switching the deck on and off you will get a little speed variation as it takes approx 2 minutes to
warm up the circuit each time even if it's only switched off for 3 seconds. This is unavoidable although we have
tried to design out the variation as much as possible.
If you measure the speed without a needle on the record the speed will not be perfect, as the speed should only
be set with the stylus tracking the record. If you don’t do this, the record will run slow once you put the stylus
on the record.
If you measure the speed within 30 seconds of putting the needle on the record the speed will not be perfect as
it takes a while to settle down.
Some people make the mistake of constantly watching the speed before the deck has settled down and the
needle has been on the record for a good 2 minutes. Strobes are very accurate and the slightest speed variation
is picked up. 0.03% variation is observable which is over 30 times the accuracy of mid-priced decks on the
market.
F I N A L C H E C K S
Your turntable is now ready to use. The following checks make sure that you have set up the turntable
correctly.
The motor pulley must not foul the underside of the platter and should be inside the platter rim.