Step-by step Michell GyroDec setup manual

(c) 2003 Werner Ogiers

(c) 2003 Kurt Wolf (photographs)

Identifying the parts

Lift base and cover unit from the carton and remove dust cover (if present). Carefully lift out platter, motor housing, power supply, etc. Remove the large polystyrene housing to enable removal of the aluminium chassis from the bottom of the carton. For Gyro SE, remove the spider from the underside of the polystyrene housing.

Then check the contents of the package:

  • one acrylic base (GyroDec: plinth; Gyro SE: spider)
  • two sets of hinges (GyroDec only)
  • one dustcover (GyroDec only)
  • three coned feet
  • three spring support studs
  • three upper spring towers with internal thrust ball
  • three spring assemblies
  • one cast aluminiun (sub)chassis or 'Mickey'
  • one inverted main bearing: the aluminium/steel lower part with oil well and shaft, the bronze upper part with sleeve, spindle, and thrust ball
  • one phial with synthetic oil
  • one platter
  • one platter nut
  • one motor, with pulley
  • one belt
  • one power supply
  • one arm adaptor plate (armboard), customised to your tonearm of choice
  • three black PVC armboard spacers, three socket screws, one Allen key
  • one L-shaped arm clamp (GyroDec only)
  • three spring covers
  • one record clamp (optional with Gyro SE, but highly recommended)

Assembling the turntable

Take a large and flat surface to spread out the parts, preferrably near to the place where the turntable will be built and then employed. Note that with a mass of near 20 kg, the GyroDec, when finished, may drive its coned feet into any soft surface (like MDF) on which it is resting.

Screw the three standing feet onto the threaded studs on the underside of the base (Gyro SE: underside of the spider). If you can adjust the level of the surface the turntable will be used on, then tighten the three coned feet. Other wise do not tighten yet, as you will use the feet themselves for final levelling.

Put the three felt rings over the spring support spindles. These rings serve to protect the acrylic base later on.

Screw the spring assemblies onto the threaded spring supports until the knurled parts of the supports are fully showing.

Locate the three threaded spring support towers onto the three support spindles on top of the acrylic base (Gyro SE: spider). When handling the support towers, make sure not to lose the thrust ball that sits inside of each threaded support.
Put the white PTFE spacer ring on top of the spring assembly base.
Locate the base and feet over the motor (GyroDec), or position the motor to the top left of the spider (Gyro SE).

Fit your tonearm, using the correct Arm Adaptor Plate. Mount the plate onto the chassis with the three black spacers and socket screws. A socket key is contained in the package. It is essential that the correct arm adaptor plate be used. Check with your authorized dealer or distributor.

It is also essential that the arm adaptor plate is in the correct orientation with respect to the turntable spindle, so as to obtain the correct overhand. For instance, in the case of our TecnoArm and compatibles such as Rega, the hole in the adaptor plate must be at the maximum distance from the spindle.

Note: for Gyro SE being used with heavy or stiff arm cables such as SME's: one of the three arm adaptor plate screws is supplied longer with a spacer clip and a locking screw. Use this screw at the backside of the arm plate to clamp the tonearm's cable horizontally at the underside of the chassis.

Carefully withdraw the steel spindle shaft from the bronze bearing assembly, taking care not to lose the thrust ball that resides in the top of the spindle hole. Screw the spindle from underneath into the threaded hole in the center of the subchassis, using a coin or a similar object inserted into the slot at the end of the spindle. Tighten.
Now lower the assembled chassis over the motor housing and at the same time over the three spring supports, ensuring the three spring bases and white PTFE spacers are seated correctly into the counterbored holes on the underside of the chassis.

(Note: the picture shows the bearing in place, but the bearing must only be mounted after the subchassis has been lowered onto the springs, see next step.)

Pour into the spindle well the amount of oil provided with the turntable, to a depth of approximately 2 mm. Carefully replace the bronze bearing housing onto the spindle shaft, making sure the thrust ball is in position. Note: this bearing is the state of the art and is of extremely high precision. Care should always be taken to avoid any damage and to keep its internals clean and dust-free.
If necessary remove the knurled platter nut from the spindle. Fit the platter.
Secure the platter in place with the platter nut, ensuring that the nut's recessed side is facing downward.

Adjusting the suspension

Place the turntable in its final position and level the base by adjusting the three standing feet. (With some supports like dedicated hi-fi equipment stands it is possible to screw in the feet maximally, then leveling the turntable by adjusting the support it is on.)
By adjusting the knurled metal portion of the three spring supports, level now the chassis to the base ...
... making sure the chassis is freely suspended with approximately 1 to 2 mm clearance between the chassis and the felt pads on the base.
By rotating the springs anti-clockwise (rotate the rubber grommets while holding the metal knurled tops), centralize the three spring support studs in their holes in the chassis (as seen from above). A correct setup of the suspension has been achieved when a light tap on the turntable's spindle results in a free and even vertical bounce for a number of seconds.

Important note: time spent perfecting this adjustment of the suspension will give optimum sound quality. It is wise to check, and correct, setup again after a few hours, as initially some creep of the spring assemblies may occur.

Put on the three spring covers when a satisfying setup has been reached.

Fit the drive belt around the smaller groove in the motor pulley and in the lower groove in the platter for 33.3rpm. For 45rpm, fit the belt around the larger groove of the motor pulley.

Make final adjustments to the arm and cartridge. Note that when using heavy phono cables to the amplifier, the cables leading from the underside of the baseboard must not rest upon the surface on which the turntable stands, as this will impede the chassis' free motion. A cable clamp is provided to secure cables to the underside of the baseboard. Allow for sufficient free looping cable between exit of tonearm and the cable clamp.

Replace the dust cover.

Once your GyroDec has been installed and is operating, very little maintenance is necessary. Should the unit require servicing, we recommend that this is carried out by one of our authorized dealers.

During the first tens of hours of use the main bearing beds in, and performance improves somewhat. The only part susceptible to wear is the bearing's thrust ball. Therefore it is wise to replace it every five years or so.

A regular light application of quality furniture polish from an aerosol spray will keep the unit and its fittings in pristine condition. Stubborn surface stains can be removed by the careful use of lead free petroleum spirit (proprietary brand lighter fuel) but under no account resort to abrasive polishes as they can remove the surface finish of the acrylic.

Mounting a second arm (Gyro SE only)

Remove the left-back lead weight from the subchassis.
Using an arm adaptor plate as template, drill three holes in the left ring of the subchassis. Tap the holes for ***.
Mount the second arm adaptor plate in the position vacated by the motor.
Mount the second tonearm. Put the motor in the front left position.

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