A Creative Demo – Part 2

In part 1, we laid out a strategy for auditioning multiple tonearms and cartridges on both a Galibier Savoie  prototype and our customer’s turntable (from another manufacturer).

In this post, we finalize how we adapted the customer’s existing armboard to work correctly with his mis-specified Reed 2A tonearm.  

Mis-specified tonearm?  These are strong words, I know.

Some forensics …

What began as a simple request to correct a mismount led us down the path of re-specifying his arm mount and adapting his armboard.  

The first thing we noticed was that his armboard had been drilled twice – neither of which was correct.

The closest we could get to the specified Baerwaald alignment point resulted in a pivot to spindle error of 5.6mm – this, with a pivoting armboard! 

A design exercise …

Without the benefit of a factory jig, mounting requires direct measurement and our Feickert protractor is an invaluable tool for this job.

Iteratively trying several mounting distances, our Feickert gauge advised a pivot to spindle distance increase of 2.4mm from the tonearm specification.  The larger mounting error noted above (5.6mm) ignored and compounded the Reed specification error. 

This positioned the customer’s Lyra cartridge in the center of the headshell slots when aligning for Baerwaald geometry.  Löfgren varies by less than a millimeter from this – enough adjustment range for even the Reed’s minimal range.

If the Reed tonearm did not have such exceptionally short adjustment slots, this re-specification wouldn’t have been necessary (Whiskey Tango Foxtrot Reed???).

How tall ARE you (with apologies to Monty Python)?

We re-drilled for  the new specification and thought we were done, only to discover that the Reed didn’t have sufficient height adjustment range to achieve a horizontal headshell – a starting point for setting VTA. 

This was not the fault of the turntable. 

The Reed is specified for a platter to armboard “drop” of about .8″ (20mm) which is about 15mm “short” of the norm. 

Statistically, this “drop” centers around 35mm (about 1-3/8″).  We specify 35mm for Galibier turntables.   We’ve seen as low as 25mm and as high as 51.

We fabricated spacers out of acrylic, and this informed us of the final armboard height.  The sound was dreadful (no surprise, due to the materials interface), but we now established the height.

Sometimes, you get lucky.

… but luck is frequently the result of doing diligence.

Looking at how to best work with the required .500″ height increase, we fabricated a  sandwich using two, .250″ thick plates of aluminum.

This reinforced the armboard and we achieved a constrained layer armboard in the process!  Not bad for a day’s work.

The photo shows the board before bonding the layers and polishing.

Come on tonearm manufacturers!

I continue to be appalled at the utter disregard for standards in our industry.

In the absence of standards, can’t we at least accept some statistical norms and design with this in mind?

Note: a special shout out goes to the designers who get it – fellows whose products play “nice” with other products.  Frank Schröder and Franc Kuzma immediately come to mind as individuals who get it.  Unfortunately, they are in the minority.