Fitting methods for turntable motors

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Belt height:

The centre of a flat belt rides on the crown of the pulley (the crown is the fattest part of the curved section of the pulley). Round belts ride in the top or bottom notch of the pulley.

On the Origin Live "short" pulley the distance from the top surface of the top plate to the crown is 6mm.
We supply a "long" pulley for use with the Linn LP12 and other decks. In this case the distance from top plate to crown is 14mm.
We also supply a "large" pulley for decks where the belt runs on the outside of the platter. The distance from top plate to crown is 6mm.

Note: latest pulleys are a special plastic for improved sound quality.

DC100 motor body is 46mm long and 26mm in diameter

DC200 motor body is 46mm long and 29mm in diameter

Rectangular mounting plate fitted to motor is 70mm x 40mm x 3mm with mounting holes spaced 60mm apart. Circular plate is XXmm in diameter and mounting holes are spaced 57mm apart.

Only one mounting hole need be used to fit either motor plate to deck. The plate may then be swivelled to set belt tension.

Additional notes

Detailed guidance notes are supplied with the kits. These additional notes are provided for guidance on some issues that may arise on individual decks. Sometimes the depth of the Origin Live motor means that a deck needs taller feet to lift it clear of the surface on which it stands. We can supply taller feet, or they can be bought easily from Maplin Electronics or most hardware stores.

Sometimes a hole needs to be cut in the deck baseboard to allow the motor to be fitted. A hole saw mounted on a drill is the best tool for the job (see hole cutting tools).

Alternatively the baseboard can be left off altogether as the voltages are no longer dangerous (12V max). Leaving off the baseboard will also improve the sound of the deck due to reduced resonance.

Plinths with thick top plates:

Sometimes the motor plate must be mounted on the top of a thick MDF top plate in a way that would add too much height. In such cases, a "milling machine" attachment in a pillar drill may be used to cut away the MDF to the correct depth and allow the motor top plate to sink into it. Alternatively a router or sharp chisel may be used.

Methods of fitting the motor:

These can vary from screwing it on using the tapped holes in the mounting plate to wedging it in position with pieces of hard foam - the motors run cold so there is no overheating problem. Note that the motor sounds best when the top plate is mounted with a single bolt. This allows easy adjustment of belt tension by simply swivelling the whole assembly. It also gives considerable scope for setting the height of the motor using a single machine screw and nuts: the nuts can be used to clamp the motor at any height along the machine screw length.

Motors with pods:

For turntables with pods which house the old motor you can adapt the pod to house the new motor - We supply a circular motor top plate for these applications which means that after unbolting the pod's existing top plate, the Origin Live motor top plate can usually be bolted to the pod using one of the redundant tapped holes - the new dc motor top plate only needs to be fastened using one bolt.

This method is not always possible and so alternative methods are to get a machine shop to tailor your old pod to fit the OL dc motor - it may need recessing to get sufficient pulley height - some people give up at this point wondering if it's worth the trouble but anyone who ever just gets up a rough working set up to see what the new motor sounds like is immediately convinced to go ahead.
One last method is simply to pack the motor into the pod by wedging it in position using pieces of hard foam, rubber, Plasticine, blutak or hot melt glue - crude though this may be it works and as the motor runs cold there is no problem on that front.

Belt Length:

We measure belts by their circumference in mm. There are two ways of doing this
a) Put a length of thread round the belt path i.e. the motor pulley and Sub-platter, mark it and then measure the length
b) Take the old belt - Measure the length of the belt pulled straight and then double the figure.

Pulley size:

We stock various pulleys which are press fitted to the motors - if you have the wrong type of pulley for your deck DO NOT TRY TO REMOVE THE PULLEY or you will probably wreck an expensive motor. The motor should be returned to us complete with pulley and we will change it over.
a) "Short pulley" 8mm diameter at crown 11mm dia overall is useful for decks where the motor is mounted close to the height of the top of the plinth.
b) "Long pulley" is useful for decks where the motor is mounted under a thin top plate e.g. the Linn LP12
c) "Large dia pulley" is designed for decks where the belt runs on the outside of the platter and is needed in order to achieve the required speeds. Height is standard on this pulley as it does not need to fit under the platter.
The pulleys are designed to run with flat and round belts so there is no need to specify a different pulley for any type of belt (round belts ride in the top or bottom rim recess).

All operating voltage ranges quoted on this page assume the DC100 motor is to be installed. If you order the DC 200 motor the voltage range may need to change - we will provide the correct switching box. The lowest operating voltage of a switch box is always noted on the rear of the switching box.