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The playing of a
record is a mechanical process to begin with.
If you stick to the folowing basic adjustments, you can enjoy the
sound of analog recordings engraved in the vinyl record.
It is not at all necessary to make things
complicated.
Compared to the modern digital formats, the analogue Lp record, with its
signal engraved in a black vinyl disc, may look poor at first glance. However do
never forget that it is still the only medium (apart from the tape recorder)
that can contain the most complete and most structured signal which can provide
great dynamics, has the widest frequency band attainable and has the most
refined detail over the entire audio spectrum and far beyond, which no other
format can deliver. The simple reason is that the original Lp is analogous in
nature.
Or to be more precise: analogous to nature.
(Note: Even if new and more complex and high
resolution digital formats are being developped and there are no appropriate
players for these formats, the recording can be engraved in a vinyl record and
can be fully enjoyed.) If the
mechanical adjustments and alignments of turntable, cartridge and arm have been
made correctly, even the simplest turntable and cartridge can bring
joy.
If the
adjustments are not correct, even the most expensive turntable cannot fullfill
its promise: the best possible sound reproduction.
All these adjustments are interrelated.
Click on the various buttons to go immediately to the
subject.
BACK 
LEVELING
THE TURNTABLE
It is of the
utmost importance to adjust the turntable with arm and phono cartridge
correctly. Place the turntable on a strong cabinet, in an audio rack or on a
special construction that is bolted to the stone wall of the listening
room. These supports should be level.
See to it that the turntable is
perfectly level also. This is essential to minimize wow and flutter.
It is
also a prerogative for the proper functioning of the phono cartridge and the
arm. Only if the turntable is level the downforce and bias (side thrust) can be
adjusted correctly.
In case of a floating subchassis (Thorens TD160, TD166,
Ariston, Linn LP12, a.o.) you should adjust the springs in such a way that the
platter is level and the subchassis does not touch the baseplate or plinth. To
check if you have done it right just push the spindle down with your
indexfinger, the platter should go down and come up always staying level. That
means that the platter should not rock or wobble. If it does you have to make
new adjustments. Adjusting is a bit difficult because you first should take off
the bottom of the plinth and then place the turntable on two small tables, on
boxes or crates, or in a rack and adjust the springs from underneath while the
table is level. The way the springs are adjusted has an influence on the final
sound. If the springs are too supple, there will be a lack of mid band presence.
If they are too short by turning the nuts too much, than the subchassis will not
be de-coupled as desired, the frequency of the floating subchassis will be too
high and the sound looses its refinement.
TOP
VERTICAL
TRACKING ANGLE (INITIAL ADJUSTMENT)
Check whether
the arm and the head shell are parallel to the record. Most manufacturers of
cartridges take care to mount the tip and cantilever in such a way that a
Vertical Tracking Angle of round and about 20 degrees is achieved when the arm
is parallel to the record. The final adjustment of the VTA will be done later
after you have adjusted the azimuth and downforce and bias have been precisely
set.
TOP
AZIMUTH
ADJUSTMENT
Now check the
cartridge seen from the front. It should be perpendicular to the record. This is
easily checked using a small mirror (as Thorens used to supply with their
turntables). A precise way of measuring the azimuth is by using a testrecord and a
voltmeter. But this can only be done after the correct downforce and bias have
been adjusted.
If you use a cheap replacement needle, check if the tip is
really well mounted and perpendicular to the record.
TOP
LATERAL
TRACKING ERROR
While
engraving the laquer disc (from which the matrix is made), the cutterhead moves
lateraly from the outside of the laquer to the inside. At all instances the
cutterdiamond makes a 90 deg. angle with the groove it has cut. This movement
can be imitated by a tangential tonearm. Most tone arms however are not
tangential or parallel tracking tonearms but radial arms which move along a
fixed radius. The result is that during play the lateral angle varies. The
diamond of the cartridge does not completely mimic the path originally made by
the cutterhead. (See also the description of the Rabco SL-8E tangential arm.)
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TOP
When using a radial arm, there is practically at
every instance a tracking error which results in a time difference between the
signals of the left and right channel. Just a few milliseconds! Therefore it is
necessary to mount the phono cartridge in the tonearm in such a way that this
time difference is kept to an absolute minimum.
The longer the arm, the
smaller the error.
Of course it is possible to build a tonearm which is much
longer than 12 inch, but the stiffness and the density of the materials used
should and the mass of the arm are important
parameters. |
TECHNICAL
SPECIFICATIONS OF THE ARM
The alignment of
cartridge and arm has to be done in accordance with the technical specifications
given by the manufacturer of the pick up arm:
* total tonearm length,
* effective
length,
* overhang and
* offset angle (angle of headshell in relation to
the armtube).
These data make it possible to determine the
correct position of the arm in case you add an arm to a motor unit.
The
overhang is the distance between needle tip and centre of the spindle. This can
be seen when the cartridge is placed above the spindle (if the arm does allow
this). The effective length is the distance between pivot and diamondtip. The
offset angle is the angle between headshell and
armtube. |
Much research has been done and many articles have been written
about how to minimize the lateral angle to the max. I do not want to bother you
with equations. After all we have to be practical.
You may decide for
yourself if you want the least distortion in the inner grooves (close to the
label) were generally the most distortion is generated. Or you may align the
cartridge in such a way that zero distortion is achieved at distances of 63 mm
and 120 mm from the spindle. You can draw a protractor yourself. Or just print
the following drawing in real size. Each gray square should measure 5
millimeter.
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Place the cartridge over the
120 mm line with the needletip precisely at the crossing. The cartridge's body
should be parallel to that line.
Now lift the cartridge, move it and place
it over the 63 mm mark. Again the needletip has to be placed exactly at the
point where the lines cross (you need to turn the platter a little by hand).
Then at that point the cartridge's body should again be parallel to the line
when the diamondtip is placed over the spot.
You have to adjust the arm and
cartridge in such a way that at both points the configuration is
exact. |
But that is probably not
enough. The above template enables you to check the error of the Lateral
Tracking Angle at every position of the arm. You can start at the small circle.
See to it that the front of the cartridge is parallel to the line marked 0°.
After that you can check at various points and see what the error is: + or - one
or more degrees. You can save this drawing and print it and enlarge it so that
the distance between A and B is 15 cm.
Not all arms were built with
the optimum geometry in mind. So in certain cases it can be necessary to shift
the cartridge in the headshell a little. This means that you are changing the
lateral tracking angle and possibly optimizing the geometry of the arm. This can
only be done if the headshell has slots.
Shifting the
cartridge makes it possible to optimize the offset angle of the tone arm and to
a certain extend the overhang and the effective
length.
If the
headshell does not have slots you can make these yourself or if you are not
handy have them made. That makes it possible to align a cartridge in a tonearm
of which you do not have specifications. Just follow the directions given above
using the template and find the lowest degree of error and
distortion.
TOP
DOWNFORCE
Apply the
amount of downforce as indicated by the manufacturer of the cartridge. Consult
the reviews and charts and tests of early editions of magazines like Hi-Fi
Choice, Hifi News & Record Review, High Fidelity if you do have the specs.
Never use a downforce that is too light. Not enough downforce is generally more
detrimental to the record groove than a downforce which is slightly too
heavy.
Each time after adjusting the downforce do listen to the result. It
takes some practise and listening experience to find the optimum downforce. If
the sound of a saxophone is too light and shows an accentuation in the midband
with a slight resonance, than the downforce (in relation to the bias setting) is
too light. If a clarinet gets too muddy the downforce is too heavy. In that case
also the soundimage will lack in space.
The downforce is hardly ever precise
the value given by the manufacturer.
Note: If you do not
use an original diamondtip offered by the manufacturer of the cartridge, you
cannot rely on the specifications of the cartridge any longer. The cheaper
replacement needles do not have the precisely cut and polished tips, the tips
may have more mass and the rubber and magnet may also be of cheaper quality.
These alter the performance of the cartridge: compliance and tracking ability,
frequency response and dynamics. In that case you also have to find the best
downforce and sidethrust which can be completely different from the values of
the original cartridge.
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READING THE
HORIZONTAL AND VERTICAL SIGNAL
When Edison
designed his Phonograph Cylinder, he engraved the sound in a vertical movement:
the needle went up and down, or as it is called "hill and dale".
Emil
Berliner from Germany designed the gramophone record and he engraved the signal
in a lateral or horizontal movement.
The combination of these two "systems"
made the stereo record possible.
In order to give both the left and right
channels the same technical parameters, this combination of lateral and vertical
engraving was turned 45 degrees. The contact of the diamond tip to both walls of
the groove should be the same, despite the fact that it changes while playing a
record.
BIAS OR
SIDETHRUST
Adjusting the bias (side thrust) can be done with the aid of a special
test record with an ungrooved section and find the amount of side thrust (in
combination with the downforce) which keeps the cartridge from moving either
towards the spindle or towards the outer edge of the Lp. If you are a
perfectionist just connect an oscilloscope alternately to the left and right
outputs of your preamplifier and check the bias adjustment by playing a test
record with separate left and right channel signals.
The use of
The Universal Record Stabilizing Ring Ring makes it possible
to choose a more precise downforce and bias. This results in a better sigtnal
with less distortion. |
A correctly
adjusted downforce combined with the right bias will give a pure stereo image
with the least distortion.
FINAL
ADJUSTMENT OF THE VERTICAL TRACKING ANGLE
After
downforce and bias have been set meticulously the VTA can be adjusted. There are
few manufacturers who guarantee an exact VTA of 20 degrees. But even then the
angle may vary slightly in your system because of the choice of downforce. Also
records have not always been cut at the precise angle of 15 ° in the early days
or 20 ° in the nineteen seventies. Cutting engineers mostly had their own
choices because they wanted to obtain better dynamics (which sometimes resulted
in edgy sound) or just a more soft sound; probably related to their own playback
systems on which they played back their own creations.
The VTA will
generally vary when playing a record which is not completely flat or is warped.
If there is continuous variation when playing a perfectly pressed Lp than it
could well be that the arm is too heavy for your cartridge. Check the parameters
of arm and cartridge. We should always bear in mind that the record groove
contains information measured in micrometers.
Nevertheless
it is very important to set the correct VTA if you want to obtain a detailed
sound with beautiful high frequencies, with warmth and attack at the same time.
Lowering the arm at the pivot so that the cartridge will lean slightly back will
give a round and less detailed sound. If you go too far, than the midband will
suffer and the sound will be dull. Adjusting the arm at the pivot so that the
cartridge leans more forward gives a more detailed sound. If the cartridge leans
too far forward the sound becomes hollow and unnatural, the harmonics will
suffer. Epecially with fineline diamondtips and the van den Hul-tip the precise
VTA is of the utmost importance. You have to find the best adjustment for good
harmonies and detail at the same time. So listen carefully! The determination of
the best VTA can only be done of course by ear.
CHOOSE THE
VTA WITH WHICH ALL RECORDS SOUND GOOD
At the end of
the nineteen seventies The Audio Critic suggested the idea of optimizing the VTA
for each and every record you would play. The idea was simple: use cardboard of
varying thickness (millimeters) and cut these to the size of the turntablemat
(or I would suggest: about 28 cm in diamter). If you have set the VTA in a way
that the cartridge is leaning slightly forward, than you can vary the VTA by
adding a cardboard "mat". The idea is to mark on record cover or innersleeve of
each Lp which cardboard-mat has to be added. Adding cardboard discs in between
record and turntablemat may give an optimum VTA but will also deteriorate the
contact of Lp and mat.
If the platter is very
high it can be necessary to add an extra baseplate. In case the arm does not
allow varying the height at the pivot, you can put a wedge between cartridge and
headshell.
IMPORTANT: Some
audiophiles add a small wedge when they think it necessary to adjust the VTA in
specific cases. Placing a wedge can help in rare cases. But placing a plate,
piece of rubber, felt, or whatever material you choose (as is sometimes advised
by so called knowledgeable audiophiles) in between cartridge and headshell
should not be done. It provides a "loose" contact between cartridge and
headshell.
Placing a material between cartridge and headshell may give (on
first hearing) the signal more speed, especially the high frequency region
becomes faster, but at the same time a correct transient which is built up from
the lowest to the highest frequencies will show a less harmonious build up.
The reason? The insertion results in a more or less prominent phase shift
(difference in time). A wedge or plate will certainly translate into a so called
bending mode, the frequency of which is followed by its second and third
harmonics (and even higher). This bending mode will color the sound.
At
first hearing there may be some refinement and more spaciousness, but after a
while it shows all too clearly that the correct build up of harmonics is
impaired.
A good
transient is dependant on each part and every material used in arm, platter,
motor, chassis, plinth and feet. The application determines whether the sound is
lively, well balanced, whether it is lacking in detail and whether it is lacking
an open, blooming midband.
The cause is mostly the use and combination of
specific materials.
The sound should simply be harmonious and should covey
the magic of instruments and performers.
If you need a small intermediate
plate between cartridge and arm to make the high frequencies more refined, than
it is clear that you are compensate for certain materials in arm and other parts
which do not have enough bandwidth.
TOP
DIAMOND
CHECK
If the
mechanical adjustments are not correctly made a distorted signal will be the
result. If you have done your best and distortion persists, and it is not caused
by the maltreated record groove, you should check the diamond tip of the
cartridge or have it checked by a professional.
A used diamond
has at its very tip very small facets that cannot be seen with the naked eye.
They are at the end of the tip and not on the sides above the groove. These
facets let the tip act as a chisel that will "cut" the grooves, especially the
grooves which contain high dynamics.
If you play with a good
tip and if downforce and side thrust are well adjusted, than you can listen to
your records many and many times without the quality diminishing.
A FINAL WORD ABOUT THE CONDITION OF THE LP AND THE ENJOYMENT OF THE
MUSIC
CHOOSE THE BEST HEADSHELL
AND FIT IT AS TIGHTLY AS POSSIBLE
If you use a tonearm with e
detachable headshell, you can optimize the soundreproduction by choosing the
headshell which will give the best harmonics, the best attack and transient and
the most even frequency curve. The main feature of aluminum is that it does not
send the energy back to the cartridge and that it is fast. Generally aluminum
provides a wide frequency band. Magnesium or a mix of aluminum and magnesium can
provide a more controlled signal reading. The high frequencies are more
restrained. Aluminum can accentuate the topfrequencies.
Another most
important point is that the headshell has to be screwed as tightly as possible.
If this is not done the sound will be unprecise and the transient will be
impaired. You can check this by playing a highquality guitar recording.
Also
the turntablemat does influence greatly the precise
reproduction.
AUDIOPHILE
REPRODUCTION
Music lovers with excellent sound reproducing systems often use expensive
phono cartridges. A price tag of $ 1000 or even $ 4000 for a cartridge is no
exception. Naturally these music lovers demand that the gramophone record is of
the highest quality: no scratches and the groove must be clean and
undamaged.
HISTORIC
PERFORMANCES
There is a second
category of collectors who go for specific artists and performances. They are
primarily concerned with the authenticity of the performance and the originality
of the recording. Minor imperfections are often unavoidable and are accepted.
Yet even collectors demand good reproduction without irritating
distortion.
Maybe you fall into both categories and can enjoy the perfect and
overwhelming rendering of a beautifully recorded symphony, opera and concert,
but also can listen with great involvement to an old imperfect
record.
CHOOSING
THE RIGHT SYSTEM
For the older records a monaural cartridge with a
spherical needletip in combination with the appropriate mass of the arm and the
appropriate downforce is needed. Sometimes one encounters a very old mono record
from the early nineteen fifties which will sound very well when played with a
crytal pick up and a downforce of even 8 grs. Some old Deutsche Gramophon or
Philips discs can benefit from this aproach. I also have discovered that old
Remington discs sound rather well on an old Garrard portable gramophone with a
small tube amplifier. I once encountered an old 4 record set of Tchaikovsky's
Yevgeny Onegin on an early Soviet label which did not sound at all with a Denon
DL103 in a rather heavy arm, but revealed all its intensity and beauty with that
same Garrard portable.
TOP
RIGHT
CONNECTIONS OF HEADSHELL LEADS
The position of the
connecting pins at the back of the cartridge varies from manufacturer to
manufacturer. The connections for the cartridge wires on the inside of the
headshell however always have the same configuration if a standard SME type
shell is used. Make the correct connections for the leads. Otherwise the
reproduction will not be in true stereo.
Also the headphone and the
loudspeakers should be connected correctly. If not, the rendering of the
musicians in the middle of the orchestra or the jazz formation will not occur
because the middle part of the image is on the outside of each channel.
TOP
CARTRIDGE LOADING
Is the sound
shrill and are the high frequencies accentuated? Or is the sound too dull and
lacks transparancy?
In any case you should check the loading of the
cartridge. The phono input of your (pre-) amplifier should have the right
capacitance to meet a specific moving magnet cartridge. The higher the
capacitance the duller the sound. So check the specifications of amplifier and
cartridge given by the manufacturers.
A moving coil cartridge should be
connected to a phono pre-preamplifier which has an input impedance of at least 2
1/2 times the value of the impedance of the cartridge's coils.
The impedance
of the input of a step-up transformer should be the same or slightly higher than
the value of the coils of the cartridge.
Check the specifications of the
cartridge and the specs of your (pre-) amplifier or step-up transformer, and see
if they match.
PLAYBACK
CHARACTERISTICS
Before the RIAA playback characteristic was generally
adopted, record companies cut their records as they thought would make the music
sound best on their own equipment.
Today there are phono stages on the
market which enable you to adjust (equalize) the right characteristic for the
playback of a variety of vintage records. There are cheap ones of about a few
hundred dollars which only do the job in mono and are sonically rather average.
The really good ones enable you to equalize all sorts of mono and stereo records
meticulously. But these are very expensive.
USE A
RECORD CLAMP/TURNTABLE WEIGHT AND A RECORD STABILIZING RING
A record clamp or record weight will improve the contact of record and
turntable mat. Vibrations and resonances will have lesser chance to be
generated. False high frequencies will not occur. The overall signal will be
more precise and the sound will have less distortion. View: The Universal Record Center Stabilizer
Weight. Eliminating distortion means
improving the signal.
A Record Stabilizing Ring (RSR) which rests on the
periphery of the record, eliminates distortion a step further and improves the
purity of the signal. View: The Universal Record
Stabilizing Ring.
AVOID
ACOUSTICAL AND MECHANICAL FEEDBACK
If you live in a
house/appartment with concrete floors, you can use an audiorack with spikes to
support your turntable. If you want a good coupling make small holes in the
carper and place the spikes directly on the concrete. Always choose a 4-legged
rack. A 3-legged one will not give firm support to amplifiers, players and
turntables because on the side where there is only one leg, the corners of the
shelfs will not be supported and will have a resonance (bending mode). Avoid
glass shelfs. Have shelves made of plywood or just use chipboard which has a
make believe plastic veneer or similar pattern. That is in my view a good
material. I myself do not use MDF because of its uneven frequency
characteristic. Furthermore it stops the sound energy instead of dissipating it.
(Do not use MDF for loudspeakercabinets either, unless you glue three or four
layers together for the baffle of the cabinet and brace the inside walls of the
cabinet.) If you do not have a concrete floor, you can have a special shelf
mounted on the wall (with strong bolts). Do not use more than one decoupling
device. Do not stack cones, rubber feet, etc. If you have a turntable with a
suspended subchassis (Thorens, Linn, etc.) do not put the base on another spring
or rubber insulator. Couple the table directly to the shelf.
TAKE CARE
OF YOUR RECORDS
To get the best quality of reproduction it is imperative
to take care of the records. That is why records need cleaning from time to
time. If you do not have access to a professional Keith Monks Record Cleaning
Machine, which provides the most efficient way to safely clean records, you can
buy a DISCO ANTISTAT, with which you bathe and brush the two sides of the record
and then let the record dry. If you use the cleaning liquid for which you will
read the recipe at the bottom of this page, the results will be very effective.
After cleaning and drying put each and every record in a clean innersleeve. If
you are handy you also can repair the covers to a certain extend and also clean
them. See: Record Cleaning.
LONG
LIVE VINYL
Install the record player in such a way
that you can easily access and use it, that is: low enough not to scratch a disc
when putting it on the platter. Always look at the record when putting the
record on the platter, lowering and lifting the arm and taking the record off
after play. Never look away, but concentrate on what you are doing. This will
diminish the risk of damaging the record. Also keep the records as clean and
dustfree as possible. Fingerprints, dust and grease are the enemies of your
records... and of your ears.
All these
measures do not only give maximal enjoyment but will also result in a longer
life of the diamond tip of the cartridge. By using good equipment the record
will keep its current quality, even after many hundreds of playings and for
another hundred years! |
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