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I've always contended that cartridge alignment could make a difference between breathtaking analog playback vastly superior to digital and compromised analog playback miserably inferior to digital......But I've never realized the importance of getting the "overhang" dead-on, in regard to vinyl playback performance. Getting this right really sets vinyl playback to the next level..... Not to mention repeatable performance in the event a stylus retip or cartridge replacement is necessary.
Enter the Feickert protractor. This device has an adjustable "slide" which has a "spike" to be set to coincide with the tonearm's horizontal pivot point. (The slide position varies with spindle to pivot distance.) With "crosshairs" on the protractor panel to set the overhang. Then the cartridge offset is adjusted to the Baerwald, Stevenson, or Lofgren alignment, the Feickert offers all three types.
Now in the past, I've used Baerwald "two point" alignment protractors, and would get the overhang "somewhat close", thinking that as long as the cartridge was aligned at both locations on the two point protractor, the overhang would be good enough..... But after starting to use the Feickert protractor, I realized that having the overhang "off" just by as little as 1.5 mm, even with the "two point" alignment seemingly dead-on, doesn't come close to having the overhang dead-on, in regard to vinyl playback performance. With the overhang dead-on, the two point alignment becomes merely a check that if one Baerwald point is dead-on, the other will be too (one point won't be "off"- the time it takes to align the cartridge goes down considerably). But the difference in playback performance was dramatic.... With all the other alignments set right (VTF, VTA, azimuth, anti-skate), the reduction of distortion, especially in the inner grooves, was audible. As was the extension at the frequency extremes. And the overtones of instruments (Miles Davis' muted trumpet, for example), become more "right" to the ear. And not to mention minimized wear on the stylus and vinyl.
I've aligned three different vinyl rigs with the Feickert protractor, which I did merely the "two point" alignment previously. The improvement in all three cases was dramatic. (The only case it wouldn't be dramatic is if the overhang was already within 0.5mm using the two-point alignment, which is possible. But not likely. And not repeatable.)
I now believe getting the Baerwald (or Stevenson/Lofgren) "two points" right in cartridge alignment isn't enough. The overhang must be dead-on as well. When this is done, you'll end up wanting to play a lot more vinyl and less digital.
Edits: 12/24/19Follow Ups:
Just for laffs, re-reading this thread, I printed out the Hoffman Protractor I've used alongside my ears ever since John Elison first posted about it.
With the same pivot to spindle, 235 MM which I measured to confirm both VPI specs and several googled sources, the came-with VPI jig puts the stylus a full 4 MM behind the Hoffman Arc. The cartridge body alignment is the same.
Merde! Now I have to futz around with Allan Keys, protractors, and the same snatch of music over and over again.
Always do right, it will please some people and astonish the rest
You may well know this already, but if not, you should be aware that VPI uses a modified version of one of the standard formulations to set its protractor. HW is primarily a classical music buff, and he has set the VPI 'tractor to minimize inner groove distortion. I run an HRX and 12" fatboy, and the VPI protractor doesn't agree with either the Dennesen Soundtraktor or the Mint LP mirrored arc 'tractor. Rather than let my OCD get the better of me, I decided to use the one that sounds best...the Dennesen won. YMMV. FYI: my Mint LP is one of the very first Yip made for 12.7 series VPI arms, and I doubt that it is accurate for my current arm. I have to twist the cartridge to the right substantially (viewed from the front of the headshell) to get the cantilever to align in the grids. I don't have to do that with the Dennesen, and the alignment with the latter has less sibilant distortion in the left channel than I get with the Mint.
I've read the HW vs. John Elison threads over the years (I have the greatest respect for both) and wonder about this gross difference of 4 MM.I have no problem with a variation in overhang influencing the voicing as a matter of taste, so to speak, but there has to be more or less tracking error with with one or the other. Certainly there is a basis for technical error in Baerwald vs. Stephenson vs. Lofgren in terms of outer and inner groove distortion.
Then there is the discusion concerning "pleasing distortion" concerning tube amps.
These things lead me to wonder if there is something similar to SRA adjustment in overhang where the conventional wisdom has higher SRA "brighter" sounding and lower, "darker". As there's nothing to watch on either Amazon, Netflix or Sling, I may just run the course of 1 MM increments to find out.
Earlier today, when I used the Hoffman to move the stylus the 4 MM additional, I was struck by a greater sense of "air" and "space" that resulted. The voice of the tenor I was listening to seemed "lighter".
Going back, the recording, Klemperer Messiah, was still pleasing but lacking the "air" and "space". So I pursued it further. I recently acquired another Messiah, the Beecham, in the Soria Series. I thought it was altogether too sepia-toned, like a 78. Playing it again as a control with the VPI alignment, my opinion didn't change. Moving the stylus forward the 4 MM, it became like any other Wilkerson produced RCA from Walthamstow Town Hall, excellent.
Always do right, it will please some people and astonish the rest
Edits: 12/25/19
nt
I've had good luck with the Moongel as a stylus cleaner..... As well as a custom Silk MC-220A SUT (50 ohm, 1:20) with the Audio Technica ART7 cartridge on the main turntable. Miles Davis "Kind of Blue" and Norah Jones "Come Away" were absolutely sublime............ (It's kind of spooky being able to notice sonic nuances when moving from standard to 180g/200g pressings.) Thanks for the tip on the Moongel.
Edits: 12/25/19
Good news, I'm glad that all worked out for you. Merry Christmas.
That's what I've used for about 20 years.
Andy
I have been using the Willis Acutrac protractor ($50) for my arm and table for awhile now. It has all 4 alignments printed. An Arc protractor is a must for overhang and makes a huge difference for sure. 20 minute easy setup and a recheck to the grid your good to go every time.
Edits: 12/24/19
I used the Feickert but it wouldn't work with my Decca cartridge because the stylus is back in the middle of the cartridge so you can't see if it's hitting the lines. I set the spindle to pivot and then returned it and use the Acutrac.
There are custom protractors available for a given spindle-to-pivot distance....... But one must accurately measure that distance, and then the provided protractor can only be used on that particular turntable and arm..... (I've seen variations of 2mm in spindle-to-pivot distances on Technics SL-1200xxx turntables.)
Yes it was made custom.I have no intentions of changing tables.
I had one for a Rega table too. Hey call me cheap!
Should you be able to easily adjust azimuth. The last step after correct alignment. I hesitated, tried the Fozgometer, didn't like it.
With azimuth properly adjusted I no longer panic at channel imbalance when recording LPs. It's the recording, not the turntable.
Once you adjust azimuth, you need to revisit the overhang and offset as both are changed simultaneously when you rotate the cartridge. If you twist clockwise, you shorten overhang and decrease offset at the same time. If you rotate anticlockwise, you lengthen overhang and increase offset.
With a unipivot, changing arm height changes azimuth.
It is a slow iterative process to optimise all parameters...
Regards Anthony
"Beauty is Truth, Truth Beauty.." Keats
I never liked the unipivot tonearms for that reason, I could never get them dialed in with the precision I wanted.
I set, naturally, the overhang and alignment using the Feickert protractor. I'll use the arc protractor to check the parallel alignment as it's easier to see. Azimuth changes with my cartridge was less than 0.5 degree, but I did check with the protractor when done.
Azimuth does not much affect channel balance. It primarily affects crosstalk. Minimizing crosstalk is the end goal of azimuth adjustments.
Actually, adjusting for azimuth changes the relative channel output between lateral and vertical modulation. When azimuth is adjusted correctly, the relative output is identical between vertical and lateral modulation proportional to the coil inductance mismatch for each channel.
A common mistake is to use a mono record to adjust for equal output from each channel. Similarly adjusting for equal crosstalk between channels is also incorrect.
Once correctly adjusted, crosstalk is often not equal between the channels but the combined average IS maximised.
Regards Anthony
"Beauty is Truth, Truth Beauty.." Keats
I didn't know about the differential effect on lateral vs vertical modulation, but are you disagreeing with me, when I say that adjusting azimuth is not a very effective way to correct for channel imbalance?
As to the remainder of your post, I didn't address those topics, but if I had, I would agree with all of it.
I own a Triplanar and a Signet Cartridge Analyzer + Shure test LP. I once used these tools to see if extreme changes in azimuth had much effect on channel vs channel output. The result was about a 1-2db difference in channel balance, moving between extremes of azimuth, and you would never run a cartridge so far off of zero degrees azimuth as I had to go to achieve measurable changes in channel output; the stylus and cantilever would eventually have been damaged, not to mention the LPs. At that time, I was testing a statement by either Victor Khomenko or B Kearns. The result agreed with their general statements.
"... but are you disagreeing with me, when I say that adjusting azimuth is not a very effective way to correct for channel imbalance?"
Hi Lew
Not at all - we are in agreement; this is specifically why I said it is a mistake to use a mono record to "correct" for channel imbalance in my previous comment since all one would be doing is introducing an error to compensate for the inherent channel imbalance.
Your original statement was that "Azimuth does not much affect channel balance. " which would be misleading to those who don't understand the subtle difference between an inherent channel imbalance and the resultant imbalance due to azimuth.
With large enough errors, when comparing vertical and lateral modulation, it is possible for the channel with the higher output to swap sides. In other words on lateral modulation you may have the L channel higher, but on vertical modulation the right channel could be higher. Since mono records have no vertical component, it is not possible to set azimuth since you aren't able to compare to the vertical output. As azimuth is adjusted to the golden position, the outputs align to be the same vertically and horizontally. In between, it is possible to have lower values of crosstalk that apparently match between channels hence the common recommendation for achieving equal crosstalk can lead to incorrect results. Similarly you can get perfectly matched output for vertical modulation (which would give a zero summed output which everyone would claim was correct azimuth) whilst still having a channel imbalance laterally.
I suspect most people don't use vertical modulation test tones for anything other than checking the channel output when summed so I would expect a good many people using Fozgometers will not be setting the true azimuth. I don't actually understand how it could even work given what I know about how the output changes across channels between vertical and lateral modulation as you change azimuth!
Perhaps someone could explain to me how the calibration process takes the differences in vertical and lateral output into account....
Anyway, as with all things vinyl, it is easy to get carried away with the settings and forget that records are very rarely flat radially which makes all this talk about "perfect alignment" a bit academic really!
All the best for the New Year!
Regards Anthony
"Beauty is Truth, Truth Beauty.." Keats
1.5 MM is a LOT!
Makes me wish the folks at Starrett Tools would make a headshell with .5 MM gradations. Or question whether the gauge you've been using is grossly incorrect.
It certainly makes a pushing-shoving-listening-repeat session worthwhile.
Always do right, it will please some people and astonish the rest
"1.5 MM is a LOT!"Apparently so...... The performance improvement with proper overhang alignment suggested that it was a lot........
But when I used merely the two null points without any reference to overhang (using a "mirror" protractor), that was the closest "error" with overhang I had for the three turntables I set up..... The other two were a good 2.0 mm and 3.0 mm off. (I was "too long" with the overhang for two of the turntables, "too short" with the third. The one I had 3.0mm off was with a 12-inch unipivot arm with adjustable pivot distance.)
"Or question whether the gauge you've been using is grossly incorrect."
It's not so much that it was "incorrect".... (The protractor I was using has a line going straight to the spindle.) It's that one can think he has the two "null" points dialed-in, but with a protractor that sets overhang, the realization that the overhang was still "off" somewhat.
Edits: 12/24/19
and it works great! I have tweaked some friends table and the results were really nice and way better than before the adjustments.
It's expensive but really worth it to me.
If the alignments all have different lengths, then why is this important?
I am assuming that the alignment parallel to the grooves is another alignment altogether which is not really related to length. I would like a fixture to get this right as I don't trust my eyes to do this correctly. Do alignment gauges help with that?
The Linear Offset jig is only going to be more accurate than other tools IF and ONLY IF you can precisely lock the pin to the pivot centre. Otherwise, overhang and offset and thrown off simultaneously.
The (so-called) optimum geometry for a record applies only to the modulation envelope.
The Baerwald nulls are optimum for an IEC compliant LP, but are not optimum for a DIN LP and certainly not ideal if 7"s are part of your normal spinning preference.
Choose whatever solution best meets your needs. Stevenson 1B is the best choice for a single "universal" setting if you intend to play everything from 7"s to 12" LPs.
Regards Anthony
"Beauty is Truth, Truth Beauty.." Keats
nt
"If the alignments all have different lengths, then why is this important?"This was the purpose of protractors that have a pivot reference- To assure correct overhang with turntables regardless of spindle-to-pivot distance.
"I am assuming that the alignment parallel to the grooves is another alignment altogether which is not really related to length.
Very true..... The overhang is adjusted first, then the offset at one of the nulls..... If the overhang is right, the two nulls should match perfectly.
"I would like a fixture to get this right as I don't trust my eyes to do this correctly. Do alignment gauges help with that?"
There is a super-expensive protractor called the SmarTractor, which works like the Feickert except it includes a built in magnifier and light to help get the alignments right..... (I use reading glasses personally.) But it costs over $600..... The Feickert costs $250.
Edits: 12/24/19
Smartractor also has interchangeable spindle holes so there's no inaccuracies due to spindle fit. It also has mirrored grid patterns.
Smartractor also has interchangeable spindle holes so there's no inaccuracies due to spindle fit. It also has mirrored grid patterns.
It's not possible to have the null-point alignment spot-on without also having overhang spot-on. They are all connected to each other. Of course, it's certainly possible to have overhang spot-on without having the correct alignment due to offset angle error, but if the cartridge is in perfect alignment at both null-points, overhang will also be correct as will offset angle.
Good luck,
John Elison
"It's not possible to have the null-point alignment spot-on without also having overhang spot-on. They are all connected to each other. Of course, it's certainly possible to have overhang spot-on without having the correct alignment due to offset angle error, but if the cartridge is in perfect alignment at both null-points, overhang will also be correct as will offset angle."
Theoretically, this should be true..... If one null is noticeably off, then the overhang is way off..... But to get the overhang right, one might have to spend hours "ping-ponging" between the two null points, and have good magnification to notice anything even slightly off with the offset....... The protractor with the pivot and overhang reference makes such adjustment a lot quicker and a lot more reliable.
> But to get the overhang right, one might have to spend hours "ping-ponging" between the two null points.
I agree with you wholeheartedly! That's why I always use an arc protractor. I believe the arc protractor is the best type of protractor because the arc allows you to quickly set overhang before setting offset using the null-point grids. I prefer the arc protractor to the pivot/overhang type protractor because I think the arc can be more accurate than locating the tonearm pivot exactly. When the stylus follows the arc, overhang is spot on and it's easy to see the slightest error in the stylus following the arc. You never really know for sure whether you're aligned to the tonearm pivot exactly.
Good luck,
John Elison
"But to get the overhang right, one might have to spend hours "ping-ponging" between the two null points, and have good magnification to notice anything even slightly off with the offset....... The protractor with the pivot and overhang reference makes such adjustment a lot quicker and a lot more reliable."I've been asserting this here for years. And you don't need an expensive unit like the Feikert to do it. the iteration or "ping ponging" as you call it, is a terrible waste of time and I think leads to errors. But the ping pongers seem to have won this debate here a long time ago.
But, of course, John is correct in that if you have the two tangencies PERFECT, the overhang will be PERFECT. If you have the overhang PERFECT and one tangency PERFECT the other tangency will be PERFECT.
Edits: 12/25/19
I agree - linear offset jigs have fewer uncertainties as long as the jig is accurate and, more importantly, the pivot centre can be located exactly.
Unfortunately, no tool is fool-proof; all of the tools have inherent issues which limit the ultimate potential accuracy. The Linear Offset jigs are no exception since any Off The Shelf product is made to a tolerance. The final arbiter of the alignment result is how well the user is able to sight the offset angle to the grid taking into account parallax, tapered cantilevers and azimuth error (which will make the tapered cantilevers in particular looked curved!).
The only way to ensure accuracy is to basically make your own to match the spindle perfectly and to verify all dimensions yourself.
I can reliably set overhang to within 10um with my custom jig. However, offset is still the weak point and I would still have to allow about 0.3° uncertainty on the offset angle.
Regards Anthony
"Beauty is Truth, Truth Beauty.." Keats
It may be that some devices are imperfectly made, but the final proof are the tangencies at the two distances from center. I use an old cart-a-lign jig and throw a laser line from spindle to arm pivot. A mirrored surface solves the parallax problem. Never had a problem.
That being said, I think the horizontal tracking angle is not the most important setting. IMO we are too obsessed over this setting. Certainly azimuth, and arguably VTA are more important. After all, HTA is wrong, to wit no tangency, most of the time. There is even an arm, well reviewed and very expensive, without an offset. Its tangency is WAY off almost all the time and is said to sound excellent. Go figure.
What John is saying is that if one null is off, both offset and overhang are off. BOTH overhang and offset must be correct in order to hit the target null point in which case the second null will be correct according to the effective Linear Offset. I say "effective" because unless you custom-make your own jig to perfectly match your spindle, there is slop. There are errors in the linear offset too due to tolerances. I have two samples of the Feickert because the trammel was "oversized" for the first one - I couldn't even insert it in the block!
Incidentally, have you measured the null point for Baerwald on your Feickert? I'm curious, because with the two samples I have, I measure ~65mm and a linear offset of 92.5mm which gives the second null at 120mm. This isn't "wrong" - in fact, it is actually significantly better than the "standard" nulls for an IEC LP on the inner grooves for a negligible penalty elsewhere.
Regards Anthony
"Beauty is Truth, Truth Beauty.." Keats
Edits: 12/24/19 12/24/19
"What John is saying is that if one null is off, both offset and overhang are off. BOTH overhang and offset must be correct in order to hit the target null point in which case the second null will be correct according to the effective Linear Offset."I think we are all saying the same thing here...... (Pardon if I wasn't clear.) I was only trying to say a dedicated overhang adjustment makes the alignments a lot easier.
"I have two samples of the Feickert because the trammel was 'oversized' for the first one - I couldn't even insert it in the block!"
I guess any product can have defective samples..........
"Incidentally, have you measured the null point for Baerwald on your Feickert? I'm curious, because with the two samples I have, I measure ~65mm and a linear offset of 92.5mm which gives the second null at 120mm. This isn't 'wrong' - in fact, it is actually significantly better than the 'standard' nulls for an IEC LP on the inner grooves for a negligible penalty elsewhere."
I measured the Baerwald nulls on the Feickert protractor. They're at 65mm and 120mm..... The mirror protractor, which was also Baerwald, measured at 66mm and 121mm..... I don't know which is more correct, but I like the result with the Feickert.
Edits: 12/24/19
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