In the shipping package, you will find the heavy Tonearm Support Assembly [TSA] where the bearings are encapsulated. A portion of the TSA can move up and down to accommodate VTA adjustments. A black ‘pear-shaped’ metal plate with threaded screw is used to attach the TSA to the turntable plinth or tonearm support plate, via the large hex nut. This pear shaped plate supports the integrated VTA device, the anti-skating device, and the lifter cylinder. In Europe, a high quality DIN/RCA cord is supplied for connecting the arm tube to the pre-amplifier.
NOTE: In North America, the DIN/RCA phono cord is not included.
Shipping package contents checklist:
Tonearm Support Assembly [TSA]
Cartridge ‘arm-tube/wand’ (which was selected according to the advice from your dealer).
Four weights with internal O-rings.
Four weights with tap screws.
A Finger lever with screws.
A Knurled nut to fasten the arm-tube/wand.
A hexagon spanner.
A syringe with silicone fluid
A thin Plexiglas rod.
A narrow piece of thick 'construction' paper.
The tonearm is usually supplied with the “arm-rest” mounted on the pick-up lifter, but an optional (separate) arm-rest can be supplied if ordered.
Plan exactly where to place the TSA base on your plinth/arm-board to allow the free movement of the rearward pointing counter-weight arm/rod. The Pivot to Spindle distance must be exactly 212 mm (8 5/16”) - or (put another way) the center of the TSA/base must be 212 mm (8 5/16’’) from the center of the turntable platter. There has to be room enough for the counterweight rod to move freely, minimally 70mm from the rear and 58mm from the side.
EDITOR NOTE: As accurate tonearm geometry is dependant on the P2S distance, a separate 'template' made of an aluminum bar is very useful in marking this distance "accurately."
FIG. 1 THE OUTLINE OF THE WHITE AREA INDICATES THE AREA NEEDED FOR THE TONEARM.
CLEARANCE & SPATIAL REQUIREMENTS
The vertical distance between the plane where the tonearm is mounted to the plane where the record is placed should be between 28 mm (1 1/8”) and 45 mm (1 3/4”). (See FIG. 1a)
NOTE: If the diameter of the turntable platter is larger than 32 cm (12 5/8”), then it is recommended to use a 12” arm-tube.
FIG. 1A HORIZONTAL VIEW OF THE MOUNTED TONEARM
To be able to adjust the vertical tracking angle (VTA) within the mechanical range of the system, the TSA base must be mounted so that the distance from the pear-shaped TSA mount and the top of the record platter is between 28-45mm. Once mounted in between this 28-45mm range from the record platter, use the VTA adjustment (by turning the VTA spindle) to position the anti-skating spring to be approximately level with the surface of the record platter.
NOTE: If the vertical distance between the mounting board and the record surface is above approx. 45 mm, then add some inert/non-resonance padding between the turntable mounting board and the TSA. Similarly, if the distance is below approx. 28 mm, then the turntable platter should be raised or, if this is not possible, padding should be added to the turntable platter - aka 'add a thick platter mat'.
Use the 70mm counterweight-rod (sticking out to the rear) as the center axis of the TSA base. Once there is plenty of room around the counterweight rod the next consideration is where the TSA base is best positioned to give the arm-tube/wand a clear ‘unfettered’ resting place, when in the arm rest. (See Fig. 1)
NOTE: If a separate arm rest is used, it should be placed so that the arm-tube (when resting on it) is at a suitable distance from the record platter.
ASSEMBLY ZERO - MOUNT THE BASE
Triple check that the mark for center of the TSA base hole and the distance to the center of the turntable platter spindle is 212 mm (8 5/16”) [For 9 inch arms].
Then drill a 20 mm (13/16”) hole with center in this mark. Also, if a separate arm rest is used, drill a 10 mm (13/32”) hole for the base for the arm rest about 155 mm (6 1/8”) in front the 20 mm hole. Insert the TSA base into the 20 mm hole such that the “narrow” end of the black pear shaped plate is pointing forwards. Then remove the piece of rubber which is squeezed in under this heavy body.
WARNING: The arm-tube/wand must be inserted into the TSA for the follow construction steps.
Place the arm-tube/wand's 5 (male) pins into the Plexiglas flange with 5 (receptacle) holes. Secure the arm-tube with the knurled nut.
The position of the black pear shaped plate must be adjusted so that the arm-tube can move in a suitable angle over the turntable platter and so that the arm-tube can rest in the arm rest in a suitable distance from the turntable platter: Move the arm-tube resting on the girder of the raised pick-up lifter all the way to the end of the girder. Then turn the pear shaped plate, so that the position of the stylus is on line with the direction from the center of knurled nut holding the arm-tube to the center of the turntable spindle.
Then put the big nut onto the thread of the base and tighten it - making sure that the base with the pear shaped plate does not turn (Fig. 1).
WARNING:Do not strip the threads of the TSA base -- by securing and rotating the base, one can get just past "finger tight". Use the spanner wrench to secure the TSA base nut with "non-excessive" force. Also, the TSA base needs to be mounted directly to the mounting board - do not place any material (less the inert/non-reasonant 'padding', if needed -- FYI The author used a lead (Pb) donut) between the base and the arm board.
ASSEMBLY ONE - MOUNT THE DIN/RCA CABLE
Plug the DIN/RCA tonearm connector into the TSA base socket (inside the bottom of the arm pillar). Make sure that the big nut holding the TSA has been tightened before pushing the DIN connector into the base. Try to avoid bending the cable too sharply in close proximity to the TSA, especially if the turntable has a floating sub chassis. The DIN/RCA cable needs unrestricted vertical movement, and it should be arranged so that it does not limit the free movements of the suspension. Remember that the ground wire should always be connected to the chassis (ground terminal) of the pre-amplifier. The chassis of the turntable - in most cases - also needs to be electrically grounded at the same ground point.
ASSEMBLY TWO - MOUNT SIDE WEIGHTS
First assemble the weights for the side rods. Place the smaller of the weights (with screws) inboard and hang one on each side rod (without tightening the screws). Then likewise take the bigger weights with screws and hang one on each side rod (FIG. 2).
FIG.2 WEIGHTS (WITH SCREWS) HANGING ON THE SIDE RODS.
Push the arm-tube towards the turntable center spindle, so that one of the side rods touches (bumps into) the VTA spindle column. Push the weights ‘in’ on this side towards the VTA device, while using the thick paper to maintain a thin space between the VTA column and the small weight. Secure the small weight in this position using hex-wrench to tighten the set-screw. With the paper separator still under pressure (to maintain the slight gap), orient the small weight so that the hex-wrench is pointing backwards and a slightly down from horizontal (see FIG. 3). Tighten the screw of this weight slightly. Make sure a ‘paper thick’ gap exists between the small weight and the larger outboard weight using this same heavy construction paper.
FIG.3 TIGHTEN THE SCREW ON SMALLER WEIGHT USING THE PAPER AS A SPACER.
Move the weights on the other side rod so that they hang symmetrically around the center line of the TSA base. Then with the heavy construction paper width, check that the smaller of the weights hanging here has the same distance from the body as the same weight on the other side (FIG. 4).
FIG. 4. ENSURE PAPER FITS SYMMETRICALLY BETWEEN SMALLER WEIGHTS
With this distance and with the hexagon key pointing backwards and a little down (FIG. 5) tighten the screw slightly.
FIG. 5. TIGHTENING SCREW OF THE SMALLER WEIGHTS.
On each side, put the paper between the bigger weight and the smaller weight and push the bigger weight slightly towards the smaller weight. Then tighten the screws a little having the hexagon key pointing backwards and about 30 up from horizontal (FIG. 6).
FIG. 6. ALL THE SIDE WEIGHTS MOUNTED SHOWN WITH THE PAPER AS SPACER BETWEEN THEM AND THE HEXAGON KEY IN ONE OF THEM.
COARSE ADJUSTMENT OF LATERAL BALANCE
Raise the pick-up lifter. Using the supplied Plexiglas rod, move the counterweight rod up by 1 mm and check that the weights on each side move up at the same time (FIG. 7). If not, loosen the screw for the larger weight that moves up first, move it slightly outwards and re-tighten the screw. Check again and re-adjust as necessary. For fine adjustment see Lateral Balance (FIG 12).
FIG. 7. RAISING THE COUNTERWEIGHT ROD 1 mm, WEIGHTS ON BOTH SIDES MUST COME UP SIMULTANEOUSLY.
ASSEMBLY THREE - MOUNT THE COUNTERWEIGHTS
Using the weights with internal O-rings (counterweight and 'tracking force' weights) insert (put) the weights onto the counterweight rod. In order to make it possible to balance all phono cartridges the tonearm is supplied with three counterweights - large, medium, and small; On the small counterweight, the hole is eccentrically positioned to allow shifting the dynamic balance, the others 'tracking-force' weights have a centrally positioned hole. Weights chosen for balancing a cartridge depend on which arm tube is used, and the total weight of the cartridge and mounting screws. With the lighter arm-tubes the small counterweight and the 'tracking force' weight is put onto the counterweight rod. With the heaviest arm-tube (blue) the large counterweight and the 'tracking force' weight is put on (in this sequence). You may have to put on more than one counterweight. Start putting onto the counterweight rod the largest counterweight. Then the smaller one etc. and at last the tracking force weight. To put on the counterweight/s and to displace them along the counterweight rod they have to simultaneously be revolved to and fro. Use as many counterweights as possible, but still there has to be room for the tracking force weight to move.
ASSEMBLY FOUR - FILL THE LIFT CYLINDER
Dismount the arm-tube/wand. The shipped syringe contains about 0.6 ml of silicone fluid. Pull the black metal piston out of the lifter cylinder and place it aside (in a completely clean place!). Then inject 0.05 ml - but absolutely no more than 0.1 ml - of the fluid behindthe lifter handle shaft inside the lifter cylinder. When doing this the lifter handle must be in "lowered" position (FIG. 8). When the fluid is injected, the tip of the syringe is "wiped off" on the shaft, and the syringe is pulled up with a little jerk thereby preventing the fluid from getting in touch with the walls of the lifter cylinder. Do not put the piston back into the lifter cylinder until the silicone fluid has merged down to the bottom of the cylinder, and hereafter the piston must not be pulled up again, as the silicone fluid would then easily stick to the walls of the lifter cylinder. If this happens the piston will descend much too slowly.
NOTE: The silicone fluid can also be used to damp the vertical mode of motion, but this is rarely advantageous. If desired anyway, please request from your supplier a separate document describing the procedure.
FIG. 8. INJECTING SILICONE INTO THE LIFTER CYLINDER
ASSEMBLY FIVE - MOUNT THE CARTRIDGE
With the arm-tube/wand in hand, the accompanying finger lever can be used to mount the cartridge on the arm-tube (FIG. 9). Use the accompanying aluminum (non-ferrous) cartridge mounting screws. Mount the arm-tube/wand to the TSA again. Given that the TSA was mounted the correct distance from the record platter center “pivot-point” a correct Baerwald geometry is now possible using a simple procedure of measuring the overhang relative to the end of the arm-tube/wand:
With NARROW arm-tube, the cartridge stylus shank should be 2 mm behind the front edge of the mounting plate.
With PRECISION arm-tubes , the correct overhang is 4 mm (5/32”) behind the front edge of the mounting plate.
Carefully push the terminal jacks of the wires unto the pins of the cartridge with a pair of tweezers. Do not force them too much and also see that you are not squeezing the thin wiring too hard. Red and green are signal and ground of the right channel. White and blue are signal and ground of the left channel. The flange of the arm-tube having 5 contact pins now is pushed down on the threaded rod on top of the arm tube. It is fastened with the accompanying knurled not, which should be tightened well with two fingers. Check that the overhang is correct - 18 mm (23/32”) for 9” arm-tubes - and adjust if necessary. The easiest way to check that the overhang is correct is to put a ruler on the turntable platter, so that one of its sides touches the turntable spindle. Then turn the turntable platter, so that the said side of the ruler points to the center of the knurled nut on top of the arm-tube. Then the arm-tube is moved so that the stylus is brought on line (above the said side of the ruler) with the direction from the center of the turntable spindle to the center of the said knurled nut. The distance from the center of the turntable spindle to the stylus (overhang) can be accurately observed by looking at the scale of the ruler between the stylus and the turntable spindle. Look at right angles to the ruler. Of course, an alignment protractor will help to align more accurately.
FIG. 9. A CARTRIDGE MOUNTED BY USING THE FINGER LEVER AND SCREWS.
ADJUSTING THE TONEARM
Using the VTA, adjust the height of the arm tube so that the anti-skating spring is at level with the record. (FIG. 1a.)
Put the tracking force weight near the end of the counterweight rod. Move the counterweight/s backwards or forwards until the arm tube is balancing in about horizontal position. When doing this, see that there is space to move a weight forwards to apply tracking force. The large counterweight gives 2 g when moved 1 indentation forwards. The medium counterweight gives 1.2 g when moved 1 indentation forwards and the small counterweight gives ½ g when moved 1 indentation forwards. Rotate the counterweight/s so that the center of gravity is pointing upwards. It also could point downwards. These two settings influence the depth and breath of the stereo image.
Apply tracking force by moving a counterweight and/or the tracking force weight forwards. If not all the tracking force is applied by moving a counterweight forwards, then also slide the tracking force weight forwards. Moving the tracking force weight forwards 1 indentation will give ½ g tracking force. When adjusting the weights they should be arranged, so that there is space on the counterweight rod to move the tracking force weight forwards and backwards. This will make it easy to audition the best setting of the tracking force.
If it appears that one counterweight can not get far enough forwards to obtain the correct tracking force, then also – if more than one counterweight is used - move another counterweight and/or the tracking force weight. If there is not enough space to move the weights forwards to give the correct tracking force a counterweight should be replaced by a smaller one. The height of the tonearm now should be fine adjusted. With the stylus resting on a record the arm base is moved downwards or upwards with the VTA device, until the arm tube is in parallel to the record, and it is checked, that the arm tube is rotated horizontally, so that the pick-up lifter can support the arm tube all the way to the center of the record. If necessary loosen the big nut and adjust.
The height of the pick-up lifter is adjusted so that the stylus is about 4 mm (5/32”) above the record, when the pick-up lifter is in “raised” position. Use the screw in the front of the black plate holding the pick-up lifter. (FIG. 10.)
FIG. 10 SCREW IN THE FRONT OF THE BLACK PLATE HOLDING THE PICK-UP LIFTER.
ADJUSTING THE HEIGHT OF THE PICKUP LIFTER
Hold the lifter handle with two fingers of your right hand, so that it is pointing straight up. Support these fingers on the black plate holding the lifter cylinder. Put the hexagon key into the screw in front of the lifter cylinder, and with your left hand loosen the screw. Then carefully raise or lower the pick-up lifter a little bit - only so much that in this position, the stylus is raised about 4 mm above the surface of the record. At the same time see that the girder is not moved horizontally, so that the arch, it is performing as seen from above, still has its center in the knurled nut on top o the arm tube. Tighten the screw again. If a separate arm rest is used, it is adjusted to a height, so that the arm tube rests on it, when the pickup lifter is in “raised” position.
CENTER OF GRAVITY
Raise the pick-up lifter. Put the black rubber between the lifter cylinder and the spring for anti-skating, so that the spring doesn’t pull. Be very careful not to bend the spring. Slide back weights, so that the stylus is “floating” at level with the record surface. Lower the pick-up lifter. Raise the cartridge as much as you can with your finger and take away the finger. The cartridge should move very slowly down, so that the stylus ends up “floating” at level with the record surface. If the center of gravity is too high the cartridge will stay up. Then it also would have been a little tricky to find the “0”-point. The center of gravity can be lowered by turning the “heavy” end of a counterweight down - if it was pointing upwards. Also the “heavy” end of the big side-weights could be turned just a little down. If the stylus is quickly moving down to the 0-point, the center of gravity is too low. Then the heavy end of the medium side weights should be turned a little up. Also the heavy end of the big side weights could be turned a little more up. After adjusting any of the weights - except the tracking force weight - the lateral balance should be adjusted again (Fig. 13). After that also the tracking force.
Azimuth (inclination of stylus as seen from the front) may have to be adjusted. When the stylus is resting on a record, the stylus - and so the cartridge - should stand at a right angle as to the record. If it does not, put the long end of the hexagon key from the plastic container into the hole in the right side of the flange of the arm-tube next to the knurled nut holding the arm-tube. See that the key “catches” the hexagon hole in the screw on top of the arm tube. (See FIG. 12.) By turning the hexagon key clockwise the arm - and so the cartridge - will be tilted to the left. By turning it counter clockwise the cartridge will be tilted to the right. Look at the front of the cartridge and the mirror image of it in the record. They have to be on line.
FIG. 12. THE HEXAGON KEY, GOING THROUGH THE ARM-TUBE FLANGE, IS READY TO TURN THE PIVOT UP OR DOWN
FINE ADJUSTMENT/TUNING OF LATERAL BALANCE
The direction of the counterweight rod extended to the stylus is the line of lateral balance. The lateral balance was coarse adjusted after mounting the weights on the side rods (see FIG 7). Fine adjustment can be done in the same way but with the arm-tube resting on the raised pick-up lifter, and the anti skating handle should be turned as far counter clockwise as possible. Usually for fine adjustment it will be enough to turn the “heavy end” of any counterweight on the counterweight rod in the direction of where the side weights are coming up first (FIG 13). Then try again to raise the counterweight rod with the Plexiglas’s rod, a.s.o. until both sides come up simultaneously. When adjusting, make sure that the stylus doesn’t touch anything.
FIG. 13. FINE ADJUSTMENT BY TURNING THE HEAVY END OF ANY COUNTERWEIGHT TO THE SIDE THAT COMES UP FIRST
NOTE: The sound image most likely will be best if the counterweights are adjusted with the center of gravity above the counterweight rod.
YOUTUBE DP8 VIDEO's
The following videos depict the changes that the adjustable balance bring to the tonearm, and display the ideal of reaching a point where the arm returns to the platter level "neutral" position automatically. There is no "vertical tracking force" [VTF] applied, so the final adjustment (after achieving this neutral balance) would be to apply the correct VTF value (via moving the counter-weight(s) towards the pivot point) to the tonearm for the cartridge.
SETTING ANTI-SKATING FORCE
The anti-skating force is adjusted with the little black handle "A" next to the pick-up lifter (FIG. 14) . The amount of anti-skating force required depends on the tracking force and the shape of the stylus; as such, no pre-calibration (by VTF) is possible.
Coarse adjustment can be done with the stylus running between the grooves next to the label of the record:
Withoutstartingtheturntablemotor,placethestylus on the flat betweenthe lead-out grooves.Thenmove (rotate) theturntableplatterslowlyforwards by hand.Thestylusshouldmoveinwardsslowly.Thenmove (rotate) theturntable platter slowlybackwards a little.The cartridge stylusshouldmoveoutwards.
Correct anti-skating is obtained when you observe the following: When you rotate the turntable platter forwards, the stylus moves inwards slowly, so that it lingers between the grooves until it gets to the center groove. Fine adjustment consists of reducing the anti-skating force a little while listening to a critical passage. If (for instance) distortion occurs in the right speaker, the handle should be turned clockwise. (The best result is obtained with a test record). The adjustment is not critical, and it is better to exert too little rather than too much anti-skating force. The range that the anti-skating handle A can move will provide enough anti-skating force for most cartridges. If the handle A is turned in the direction of the arrow (clockwise) the anti-skating will increase - and decrease if it is turned the opposite way (counter-clockwise).
If the handle cannot be turned enough to get suffient anti-skating or to get less anti-skating, then the disc under the screw "B" should be adjusted. Hold it with two fingers of the left hand, while the screw B is loosened with a small screwdriver (careful to use a screwdriver that seat fully -- otherwise you can strip it), and the disc is turned ½ revolution [or more] in either direction of the arrow for more or less anti-skating force. Tighten the screw "B" to complete the proceedure. The anti-skating then can be adjusted with the handle A in a range with more or less anti-skating than before.
NOTE: The stability of the 'horizontal mode of motion' is obtained as a co-function between the heavy side-weights and the damping in the horizontal plane. If the arm-tube is moved horizontally in and out with a hand, you will detect resistance to movement. This is normal and expected. Only if the arm-tube is moved very slowly there will be no resistance.
FIG. 14. ADJUSTMENT OF ANTI-SKATING
COMMENT ON PRECISION ARM TUBES
PRECISION arm tubes are supplied in “red” and “blue” versions only. They have a wide and very precisely ground mounting plane to assure a good mechanical contact to cartridges that have a similar large and accurate mounting plane. The PRECISION arm-tubes are 4 mm (5/32”) longer than the NARROW ones in the forward direction.
COMMENT ON 12” ARM-TUBES
12” arm tubes are supplied in “red” and “blue” versions only. They are supplied only with the narrow head-shell.
In the section Mounting the base it is described how the position of the 20 mm (13/16”) hole is found. For 12” arm-tubes the distance from the center of this hole to the center of the turntable patter should be 294.1 mm (11 9/16”).
If the base is mounted at above distance from the center of the turntable platter, the stylus should be positioned a little behind the front edge of the black plane of the arm tube. After mounting check that the overhang - 13.3 mm (17/32”) - is correct and adjust if necessary. With 12” arm-tubes more counterweights should be used than with 9” arm-tubes. With the heaviest 12” arm-tube “blue” usually all the weights should be on the counterweight rod. If even the cartridge is heavy, the weights should be put on in opposite sequence, so that the large counterweight is at the end of the counterweight rod.