Time to choose: Baerwald, Lofgren, Stevenson ?

Hi all,

As far as using the designer’s intended alignment, this is one of the few areas where I say experiment (ignore the designer) and see what works for you.

Assuming a fixed mount on your tonearm (meaning that you can’t change your pivot-spindle distance), then the overhang difference between Baerwaald and Stephenson is less than 4mm.

The offset angle difference is minimal, and given the variance in cartridges’ cantilever alignment, the stars might just align and result in your having a cartridge whose body is "square" to the headshell ... or not. IOW, I don’t view twisting a cartridge mount to be a big deal.

You might find it entertaining to download the John Ellison spreadsheet on the Enjoy the Music website (I maintain a link on my main support page to it) and look at the distortion numbers generated as well as the geometric parameters.

Personally, I look at the Stephenson approach (optimizing for the inner groove at the expense of increased average distortion) to be less preferable than Baerwaald, but everyone is different, which is why I agree with Raul’s advice to play and see what works for you.

As far as Stephenson and optimizing symphonic playback is concerned (i.e. it's all about the crescendo at the end of the record), I view this in the same way that I view people who don't play half of their records because they don't sound good. 

Why would you sacrifice the delicate section(s) over the bulk of the record to improve the last part? 

This is somewhat like a mother saying to her kids:  "finish those terrible tasting peas on your plate, and then you get to have dessert".  I'd rather cook vegetables that my kid likes ;-)

Cheers,
Thom @ Galibier Design

Thom, I don't "view" it one or the other, either.  But my recommendation is based on actual real life experience.  At least one other person, reporting on Vinyl Engine, had the same experience.  I would not argue that others who do it do not seem to perceive that twisting the cartridge in the headshell per se causes any distortion.  Here is my hypothesis for the cause of the distortion:  When the cantilever is not aligned with the long axis of the headshell, then forces acting in the vertical direction on the cantilever are unevenly distributed back to the tonearm pivot point.

Fascinating reading. Anyone tried to do the alignment by ear? That's what counts, doesn't it, the way it sounds ?
No wonder I like tape, not much vinyl.

Hi Lew,

I was basing my comments on the fact cartridges are not perfectly manufactured, and the more expensive ones are by no means immune to this. They very frequently have cantilevers that are misaligned to some degree (not perpendicular to the two mounting screws holes).

So, you’re frequently twisting the cartridge in the headshell to achieve an alignment with any geometry you choose.

One’s altered alignment could have the effect of "fixing" this square-ness relative to some reference point on the headshell or alternatively making it worse.

Ultimately however, I think this goes to the greater point - that one’s preference for a distortion profile of a particular alignment will be more noticeable to the listener than any potential stray resonances resulting from going off the reservation by choosing an alternate alignment.

I just don’t know how one could separate all of the variables to test the stray resonance hypothesis, so in the end, it becomes a try it and see (different alignments) sort of thing.

I’ve been wrong before, and by no means am stating gospel here, but regarding your hypothesis, one could argue that a slight additional skewing of a cartridge (we’re talking a fraction of a degree) could break up standing waves.

I just ran through the Ellison spreadsheet (I only have Baerwaald and Loefgren sheets set up - not Stephenson). I hate to call anything trivial, but in this example, we're looking at an offset angle difference of 0.0402 degree difference between the two alignments.

I worked off the assumption that anyone doing this has a fixed mount armboard - that they cannot change the pivot to spindle distance, so this will be held constant. Here's how the numbers play out for a tonearm with a nominal 250mm effective length:

Baerwaald:

Pivot-spindle: 233.0331 (held constant)
Effective length: 249.5657
Overhang: 16.5326
Offset angle: 21.9891

Loefgren:

Pivot-spindle: 233.0331 (held constant)
Effective length: 250.0000
Overhang: 16.9669
Offset angle: 21.9489

Cheers,
Thom @ Galibier Design

I'm generally in the same camp as Lewm on this one: I align the cartridges based on the alignment the tonearm was designed for. Since most of my tonearms use removable head shells and were designed for a 52mm distance from the head shell connection to the stylus, this has the added benefit that the cartridge needs minimal if any realigning when put into another tonearm.