Measure Twice, Cut Once
We've recently received a flurry of inquiries about mounting issues - questions which periodically arrive in our inbox in clusters.
More often than not, the problems can be traced to a combination of a mis-specified tonearm mount (or a mismount), an outlier cartridge, and either/both tonearm or turntable design that provides limited adjustment.
All too many turntable manufacturers exercise faith in tonearm manufacturers' specifications.
Their faith is misplaced (click here for one example).
In another example, we pointed an issue out to one tonearm designer. Some 7 years later, Michael Fremer noted the persistence of this issue.
Whether or not the fault lies with a poorly specified tonearm mount or a drilling error, the user is faced with an installation for which they can't align their cartridge.
Last Line of Defense
As a turntable manufacturer, we're like a goaltender in hockey. We're the last line of defense for errors made in front of us.
This problem can easily be mitigated with adjustable armboards. Our Galibier armboards have a precision pivot-spindle adjustment range of .250" in both directions (a .500" total adjustment range).
This allows for both experimentation with alternate geometries as well as facilitating "recovery" from a mis-mount due to issues noted above.
Lundquist With the Save
Out of Range
Dynavector XV1s Stylus Offset
Typically, a customer will report having run out of adjustment range in their headshell when attempting a standard alignment - whether it be Baerwaald, Löfgren, Stevenson, or others.
While tonearm designs should anticipate this, an outlier cartridge can potentially exacerbate this adjustment range issue.
There is no industry standard for the location of the stylus relative to the cartridge's mounting bolt holes and this has an effect on the effective length (the key reason for adjustment slots in the headshell).
The XV1s shown here, is an example of a "short" stylus. Statistically, most styli are offset by 9.25-9.50mm from the mounting holes. The Dynavector falls only slightly outside the norm and this should not be a problem for a well-specified tonearm.
Unusual Geometries
One recent example is an SAT arm which specifies a pivot to spindle distance of 212.2mm and an effective length of 235mm.
This effective length is nearly 4mm longer than what Baerwaald predicts for a 212.2mm mounting distance. The customer ran out of forward adjustment range due to "short" headshell slots.
Whether or not the mount was correct (we did not mount this arm), I don't understand the limited adjustment range in the headshell slots for a tonearm costing $30,000.
I advised the customer to align for Baerwaald and not look back.
SAT Geometry
More Than One "Right" Answer
On Tonearm Geometry
The good news is that apart from drastic errors, you can likely compensate with an alternate geometry in many cases.
You may be puzzled at this point, and I direct you to this blog post where I lay out various geometries and their distortion characteristics.
All of this is to say that the SAT geometry is by no means wrong, but it is unconventional, and you will not find a protractor from Wally Tools or others with SAT's alignment specification. This is also the case with many classic Japanese tonearms.
In short, there are many viable geometries with minimal differences between them - in spite of what advocates of one alignment over another might tell you, and selecting an alternate geometry may bail you out of an alignment issue.
