Cartridge Alignment Protractors
On this page you can download free cartridge alignment protractors for quick and accurate alignment of cartridge / stylus overhang, offset and null points. We have truly universal two-point tools such as the Stupid Protractor, and tonearm specific types for Audiocraft, Helius, Heybrook, Linn, Rega and Thorens, all with easy to follow instructions detailing how to align a cartridge.
To determine which protractor is suitable for your tonearm please read Seb's Protractor User Guide and please check scale carefully after printing and resize if necessary.
Other useful alignment tools
Tonearm Database
Mounting dimensions and alignment data for most turntables and tonearms - the original and best!
Alignment Calculator Pro
The latest version of the VE alignment calculator is the swiss army knife of alignment tools, now with comparison plots of tracking error and distortion for up to 4 tonearms/alignments
- Compare your arms standard geometry to the most popular alignment geometries
- Calculate optimised alignment geometry for your tonearm
- Compare geometry and distortion of up to 4 different tonearms
- Optimise alignment for your own record collection by adjusting for optimal groove radii
- Discover the optimal mounting distance for a known effective length
- Calculate geometry for your DIY tonearm design
Overhang Shift Calculator
Assess the effects of changing stylus overhang while keeping the original angle of the cartridge in the headshell
Generic (universal) protractors
Stupid Protractors
A pair of universal two-point protractors, one using the more common Baerwald alignment method as used on 99% of commercial products and the other Loefgren B (see Seb's user guide above for an explanation of the difference). Simple, accurate and widely compatible. If you aren't sure which type to use and want a free alternative to the common shop bought designs, download this one.
Stevenson alignment protractor
Another universal protractor, this time using the Stevenson alignment method with null points at 60.325 mm and 117.42 mm. This is especially useful for arms which have limited room in the headshell slots and can't be aligned satisfactorily with a Baerwald type.
Chpratz Protractor
Designed to allow users to align their cartridge at any two null points between 60 and 150mm. A quick and easy way for experimenters to judge the sonic merits of different alignment methods. For example, this could be used in conjunction with the tonearm database to compare the tonearm manufacturers alignment with the popular Baerwald type found in most aftermarket protractors.
Universal Stuff Protractor V.2.0
A mirror protractor, a variation on the classic two-point protractor - suitable for experienced users only!
Kearns Universal Arc protractor
The Arc protractor is suitable as a cartridge alignment protractor for specific tonearm lengths / mounting distances only (see instructions enclosed)
Turntable specific protractors
These protractors are tonearm specific or use alternative alignment methodology.
AudioCraft AC300C protractor
Suitable for the Audiocraft AC300C tonearm only
Helius Aureus protractor
Suitable for the Helius Aureus tonearm only
Heybrook Universal alignment protractor
Universal two-point protractor that uses Heybrooks chosen null points of 63.5 and 120mm
Linn Ittok / LVX / LVX+ protractor / mounting template
This tool is suitable for accurate mounting and alignment of all Linn mounting pattern tonearms.
Seb's Arc Protractors
Arc protractors allow super fast, accurate cartridge alignment.
Please Note The alignment curve on an arc protractor is only suitable for the stated mounting distance.
DO NOT use an arc protractor unless it matches your mounting distance exactly.
Linn Baerwald alignment protractor
Suitable for Linn tonearms mounted at 211mm mounting distance. Print on A3 sized paper. Includes integral strobe disc in 3 versions, 50Hz, 60Hz and 300Hz.
Rega Baerwald alignment protractor v.2
Suitable for Rega tonearms only, mounted at exactly 222mm (standard) mounting distance. This single point design is especially quick and easy to use and includes an arc for rapid double checking.
Rega Stevenson alignment protractor v.2
Suitable for Rega tonearms mounted at exactly 222mm (standard) mounting distance. Identical to the Baerwald protractor above but designed using Stevenson null points which gives alignment closer to Regas and is useful when the headshell slots don't give enough room to align your chosen cartridge using the Baerwald design.
Technics Arc protractor
Suitable for those Technics turntables that have an arm mounting distance of exactly 215mm, such as the SL-1200/1210/1300/1400/1500/1600 etc. Please check the tonearm database for the mounting distance of your arm before using this protractor.
Note that Technics arms do not use baerwald alignment as standard, so you may have to skew the cartridge in the headshell in order to align with arc.
Technics Arc Protractor Instructions
Thorens Arc protractor v.2
Suitable for those Thorens tonearms that have a mounting distance of exactly 215.6mm. See enclosed instructions for compatible tonearms.
All Cartridge / Tonearm alignment protractors on this page are freely downloadable for non-commercial use.
Comments
Arc Protractor
Read the instructions for the Technics Arc protractor (above) for the correct procedure. Basically the arc is used to set overhang and the grid to set offset angle.
Regards,
JaS
Drawing Scale
I double checked the drawing using the PDF dimension tool and the AA and BB lines are perfectly to scale. Any changes in scale after printing are down to the printer/printer driver.
Regards,
JaS
Overhang
Hi,
You should first push the cartridge forward in the headshell to follow the arc - this sets the overhang. If you run out of room in the slots it may not be possible to use Baerwald alignment with that cartridge. The cartridge should end up 2.8mm further forward than when using Technics original alignment, but the distance between the stylus tip and the cartridge mounting bolts varies from model to model so it may not be possible with the DL-160?
Regards,
JaS
Short Overhang
To be honest I'd be tempted to use an overhang gauge and stick with the standard overhang. Without knowing the original offset angle it's hard to know what sort of alignment they were aiming for, or what is possible within the current headshell?
Overhang Gauge
Hi,
Yes, if you keep the cartridge square and use the gauge then that will give you the original alignment, which should give reasonable results?
If you want to experiment further you could attempt to measure the offset angle (the angle between the cantilever and a line drawn between the stylus tip and the horizontal pivot point of the arm), or maybe experiment with inputting different angles into the Alignment Comparator until you get a decent distortion curve, then use Conrad Hoffman's arc protractor generator to print out an alignment template to see if you can align to it? It's a bit involved though, so probably a project for a rainy day (it was pouring it down the week I wrote the alignment calculator/comparator!).
Regards,
JaS
How To Use a Two Point Protractor
Hi,
There seems to be some confusion about how to use these protractors? Neither type is kept stationary between points - for this you would need a specific arc protractor designed for your mounting distance.
Here are the basics for correct use of a two-point protractor:
(1) lower the stylus onto the inner null point (rotating the protractor as required), then adjust the for/aft position of the cartridge in the headshell until the cantilever/cartridge body is parallel with the grid lines when the stylus is placed back on the point.
(2) lower the stylus onto the outer null point (rotating the protractor as required). If the cantilever/cartridge body is not parallel to the grid lines at this point you should twist the cartridge in the headshell to adjust the offset angle (without changing the overhang set in the first step).
(3) repeat steps 1 and 2 making minor adjustments as necessary
The advantage of a sight-line type (such as the KWillis protractor) is that you set the overhang and offset angle at the first point, then you just have to rotate the protractor* to check the second point, so it should be quicker. However, it's not always easy to point the sight-line accurately at the pivot point so if there is misalignment at the second point you should then use it as you would a two-point protractor to correct it.
For each alignment method (Stevenson, Baerwald and Lofgren B) the two-point protractors above will give identical alignment to the KWillis protractor when used correctly.
Regards,
JaS
* note that the angle between the grid line radii on the KWillis protractor reduces the amount you need to rotate the protractor when checking the second point, but the correct angle between these points is different for every mounting distance so you shouldn't attempt to force alignment at both points while the protractor is held stationary.
Mounting Distance
Hi,
You won't be able to align a cartridge if you mount the arm at 233mm. It would require an effective length of 249.5mm for Baerwald and the arm isn't long enough to achieve this. Indeed, it's only just long enough to achieve a 239.3mm effective length when mounted at 222mm.
The correct mounting distance for all Rega arms whether original or OEM is 222mm.
Regards,
JaS
Geometry
Hi,
Used correctly the Stupid protractor works well - the Baerwald null points will provide the lowest peak error, while the Lofgren B will give the lowest average RMS error (with a slight increase at the inner and outer grooves). Alternatively you could use Conrad Hoffman's Arc protractor generator (see the thread in the cartridge forum) to print out an arc protractor specifically for your arm length - these are quicker to use than a traditional two-point type, but if you go this route be sure to read the instructions carefully.
Regards,
JaS
Fidelity Research
Hi,
You can use any universal 2-point protractor, but as standard your arm uses a geometry closest to Stevenson so this would leave your cartridge more central in the slots than other versions, offering better compatibility with cartridges that have an unusually long mounting hole to stylus tip measurement.
Regards,
JaS
Alignment
Hi,
Baerwald & Loefgren B produce very low levels of tracing error within the playing area. They don't have a 'sound' as such so if it sounds bad either something else is amiss or you need to double check how you're using the protractor?
The SL1210 mk2 has a mounting distance (pivot to spindle) of 215mm and an effective length of 230mm (stylus to pivot when using the standard alignment tool).
52mm is the standard distance from the back of the headshell mounting surface to the stylus tip, not the overhang. Overhang is the amount the stylus tip overhangs the centre of the spindle once aligned - standard this is 15mm, but using a Baerwald protractor you will end up with 17.8mm of overhang and the cartridge 3mm further forward in the headshell (but lower tracing error).
FWIW you don't need to measure the overhang or offset angle, just align to the protractor as described in the instructions and it will be set.
Regards,
JaS
Overhang
Hi,
The 15mm overhang figure is only applicable to the original alignment method. If you want to keep the original overhang distance/offset angle you could try making your own two point protractor? According to Jelco's specs the original null points work out at 68.7 / 129.9mm so marking these on a piece of card would give you the radii at which the stylus should be perpendicular to the groove (if Jelco's figures are accurate).
Alternatively you would get slightly lower maximum and average tracing distortion by using the Baerwald Stupid Protractor, but you will end up with 13.4mm overhang and an 18 degree offset angle when aligned accurately to it. There should be room in the headshell but the cartridge will end up slightly skewed in the shell if that bothers you.
Regards,
JaS
custom protractor
Hi,
To make a custom protractor, you firstly need to draw a straight line on a piece of card/paper and near one end mark a line for the spindle centre line (where you are going to punch/score the spindle hole). Then measure from this centre line the two null point distances and draw two lines at 90 degrees - these will be the two points at which you will place the stylus to check tangency. If you have Illustrator or a CAD program it's easier as you can more accurately draw the lines and maybe add a grid. Alternatively you could download the Chpratz Protractor above but it is only accurate to 1mm so you would be looking for alignment at the 69 and 130mm lines.
Regards,
JaS
protractor
Hi,
The Rega protractors are only suitable for arms with a 222mm mounting/pivot to spindle distance. Any of the universal protractors (Baerwald, Stevenson, Loefgren B) are suitable.
Regards,
JaS
Rega/NAD
Hi,
The scan of the original single point Rega protractor in the library is suitable, or you could use the Rega Baerwald/Stevenson arc protractors for alternative alignments which give theoretically lower tracking error/distortion.
Regards,
JaS
SME protractor
Hi,
For serial numbers below 439606 you can use the two-point 'Stevenson Protractor', for later arms the 'Baerwald Stupid Protractor' is suitable.
Regards,
JaS
Geometry
Hi
Standard effective length for most 215mm Technics arms is 230mm (mounting distance + overhang). The arc protractor uses Baerwald geometry for lower distortion which requires more overhang (cartridge further forward in the slots) and hence a longer effective length.
Regards,
JaS