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Cartridge Set Up

Bairnstorm

Bairnstorm

pfm Member
I have a 12 inch Ortofon and it is difficult to find a suitable protractor.

Where do you find a decent way to set up your cartridge? What is the most accurate way? Does it matter?

Thanks
 
It certainly does matter and there are a number of protractors on the market. The best, apart from the SmartTractor is the more affordable Dr. Feickert. I have the original which I use to set up my 12" arms. I'm sure that others with more market knowledge will be along to suggest alternatives.

Whereas VTF and VTA, azimuth etc can be set up without a protractor, overhang, a crucial measurement, can't, a.f.a.I.k.
 
Bairnstorm said:
I have a 12 inch Ortofon and it is difficult to find a suitable protractor.

Where do you find a decent way to set up your cartridge? What is the most accurate way? Does it matter?

Thanks
Click to expand...

If you don't mind paying for a universal alignment jig like the Feickert or SMARTractor, these will both save time and frustration. But, you can achieve accurate alignment by creating an arc template using Conrad Hoffman's free Arc Template Generator which you can download from http://www.conradhoffman.com/chsw.htm (it's suitable only for Windows PCs). To create a template, all you need is to enter the tonearm's spindle-pivot (mounting) distance, and the preferred alignment geometry (Baerwald, Loefgren B or Stevenson) and away you go, at least once printer scaling is correct. Setting cartridge overhang using an arc template like this is fiddly but ultimately very accurate, and then you can go on to set the cartridge 'twist' in the headshell to align to either of the template's grids. The downside to using arc templates is the time it takes to get things right, but time is on the whole free.

If you are using a fixed head cartridge like an SPU, then you can only set the tonearm at Ortofon's recommended spindle-pivot distance, and that's it.
 
The null points for a standard 12" LP (inner groove 60mm Outer 146mm) are the same as for 9" arms. In the case of Baerwald / Loegren B alignment these are 66.04 & 120.09. Any good two point alignment protractor with the correct null points should work.
 
My arm is a TA 210 so fairly modern.

I have been using the single protractor in the HiFi News but downloaded the Conrad Hoffman protractor last week.

I found that the set up was a few mil out and having now set it up properly the difference in sound is like a major upgrade! Much better bass, soundstage and natural treble.

Thanks for the comments.
 
Yes, the careful thing to look out for with the Conrad Hoffman arc protractor is to make sure your printer prints to scale. Be certain to verify the provided millimeter references in both axes - that's what the printer correction factor is for.

For the next level in accuracy, I recommend the Mint LP Best tractor which is custom inscribed for one tonearm only. The glass mirrored surface is helpful with lessening parallax. https://mintlp.com/best.htm
 
Bairnstorm said:
My arm is a TA 210 so fairly modern.

I have been using the single protractor in the HiFi News but downloaded the Conrad Hoffman protractor last week.

I found that the set up was a few mil out and having now set it up properly the difference in sound is like a major upgrade! Much better bass, soundstage and natural treble.

Thanks for the comments.
Click to expand...
Glad to hear that you are enjoying an improvement.

Interestingly, TA-210 is the only currently available 12" Ortofon in which the geometry has been properly optimized for Løfgren 'A'. Specifically, when mounted at the indicated pivot to spindle distance, and with overhang set to 12.4mm, combined with the in-built angular offset, a cartridge that is set square to the headshell will null at both 66mm and 121mm radii.

IOWs, assuming your pivot to spindle distance is exactly 316.6mm, you could have just as easily used a metric scale ruler to achieve Løfgren 'A'. If one isn't right on the pivot to stylus distance then a protractor is required.
 
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Slight amendment.

Last night I listened to There's the Rub and the left guitar was stronger than the right so this morning tried setting up the cartridge again with the Hoffman protractor.

Ortofon have the spindle to pivot as 316.6mm and I was told that Thorens put the arm on at the factory but when I measured it (not to atomic accuracy) it was 315mm.

It is difficult to adjust the arm as the wiring is to RCA sockets and it is all carbon fibre surround with weird bolts.

I decided to print off another Hoffman protractor with the spindle/pivot at 315 but keep the nulls the same at 66 and 120.9. I have managed to get it pretty much there and now both guitars are the same level.

FUBB sounds spectacular.

There doesn't seem a huge amount in the measurements for the two protractors so feel it is not causing a huge problem and the Shibata tip seems happier. I didn't realise they were so fussy with set up.
 
As one goes off tangent, it is second harmonic distortion that rises between and without the nulls. WRT how channel imbalance (and stereo separation) relates to alignment, it is lateral azimuth that is most relevant. With gimbal tonearms that don't have the bearing yoke aligned to the same headshell offset, nor a facility to adjust headshell azimuth, setting the tonearm too low or too high will alter azimuth and negatively affect channel balance/separation; regardless, your TA-210 does have offset bearings.

I would suggest having a look at the headshell/cartridge from front on whilst playing. Many (not all) universal headshells are designed with a friction fit that allows rotation of the headshell relative to the bayonet plug that fits into the arm tube socket. Others, classic SME for example, allow the tonearm socket to be rotated within the tonearm tube; with many aftermarket types having a set screw within the headshell.

CAUTION: the TA-210 manual does not mention headshell azimuth as being adjustable.

As to your Shibata tip, as mentioned previously, these are sensitive to SRA, i.e. deviation from vertical orientation of the stylus tips major radius R when looked at in elevation view from side on. Being off here affects resolution, particularly HF detail more so than outright distortion per se. Minor adjustments to VTF will alter VTA/SRA more so than will minor height adjustments; e.g. WRT the previous example of a 2mm spacer providing a mere 0.5º angular increase with a 240mm effective length tonearm; a .1gm change of VTF would provide more angular change (a circa 1.5º change in VTA/SRA). As such, you are likely to find that, if your arm tube is set level during play with the cartridge manufacturers suggested downforce, increasing by 0.1g may do a lot more than allow higher modulation levels to be tracked securely; much more of what the tip profile is capable of may be revealed across an entire disc side as well. With exotic tip profiles, minor tracking force adjustment is akin to using the focus ring on an SLR camera.

Apheta projection - note suspension not under load, hence the 27º cantilever angle goal, indicating that the recommended VTF of 1.75g causes a -4º deflection to 23º, Rega's preferred cantilever VTA at recommended downforce (image credit: Rega Research Ltd.):
apheta-3.jpg


Azimuth misalignment example, reduced channel separation combined with channel imbalance:
Off-marked.jpg
 
Hi Craig, I can alter azimuth and raise or lower the VTA so that is all well.

The stereo spread is uniform across the soundstage and it is probably the best I have achieved so far.

Cheers for the info and tips. They are not easy to set up. My ESCO tip Koetsu is much more forgiving.
 
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