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In Reply to: RE: REVIEW: VPI Industries Prime Turntables posted by bill_stevenson@bellsouth.net on November 20, 2015 at 12:56:50
> One of the little frustrations that I had with set up is that the nominal spec for tonearm pivot point to spindle on the Prime is 258 mm, but mine
> for some reason was actually 261.5 mm. This is a minor difficulty, but Matt Weisfeld actually offered to replace my turntable over it.
Actually, this is a major problem. You will find that many, if not most cartridges will not be able to achieve proper alignment with pivot-to-spindle mounting distance out-of-spec by 3.5-mm. Headshell slots are normally not long enough to compensate for this much error. I would recommend allowing Mat Weisfeld to replace your turntable if the pivot-to-spindle distance cannot be corrected.
Good luck,
John Elison
Follow Ups:
Hi John,
While I agree with you that 3.5 mm is too far out to be acceptable, my solution to the problem does not include throwing the baby out with the bathwater. The solution is to use a protractor set up for the actual distance between the arm pivot and the spindle. Nominal values are frequently not exact anyway. And of course using an arc and setting at an outer and inner point along the arc is quite important. I know I"m preaching to the choir, but state this for the benefit of other participants.
You may recollect that when we first corresponded it was because I was having trouble dialing my Prime in. The reason I knew it wasn't doing it's best is because my KAB SL1200 sits right beside it and the comparison told me something wasn't right. The Prime does sound better than the Technics, but even now the difference is not great and at the beginning it was the other way around. Take care.
Bill
I will just chime in on the Prime issue. My Prime had a SP distance of 256 and change. Off spec. I did as Harry recommended and loosened the screws in the arm base. I am now at 557.955 .05 off. I used electronic calipers which ran about $70 bucks off amazon (cheaper pairs are available). Note if you adjust PS put a note card between the screw driver and VTA/tower to avoid marking up the tower/base up.
I really don't know if I really hear a difference. Table sounds amazing as it always has. It is sounding very good today so maybe.
I also used the Conrad Hoffman software to compare the alignment of VPI Jig. It's extremely close. Like not sure there is any difference using 40x loupe close. I will take another look at it later when I am more focused, but certain there is not much difference. I would love to think I will get a nice bump in performance but when it's hard to see the difference with a 40x loupe I am not sure I will get a bump at all.
That being said I was dead on with the VPI Jig when I first set it. All of these things have taught me a few lessons.
First: these specs are very hard to hit on the head. I am betting many many turntables of various brands are slightly off spec. Especially considering these things are shipped. Finally being slightly off (2mm) does not kill a 4k record player. They still sound great.
Second: I would say the mint is worth the investment. If you supposable care to the last MM if something is off spec using a print out protractor is not cutting it. First how good is the printer you are using. And if the paper or transparency has any play bumps from not being completely flat or has any movement you might as well quite because the distances we are talk about are so small to begin with if you are not dead accurate you are wasting your time.
I do believe something machined to exact spec probably sounds better. I think the question is how much better and are you willing to spent the time, effort and money to do it. Can anyone say diminishing returns.
In one of the reviews of the Prime it is compared to a Basis 2500 table. The Basis cost 17K.
"Compared to the Prime, the Basis 2500 Signature turntable offers a warmer overall tonal balance with a bit more low level information. Harmonic trails last just a little longer. Singers have a bit more depth and warmth. These are often the kinds of differences we hear with different interconnects or cartridges, but using the same interconnects and cartridge on both turntables suggests that the Basis is more resolving, as it should be considering the difference in cost."
This about says it all for me. At my average joe wages I can swing a Prime but will most likely never be able to afford the Basis but lets be real its better but not enough for someone of my means to be swayed enough to 4x times more.
After actually checking this SP issue out I have to agree more with HW. It does not make a earth shattering difference if your SP is off a little. I bet you a million bucks you have enjoyed tables that were way off spec. In addition the Prime can be adjusted. If you need this level of accuracy in every measurement of a turntable get your check book out or get a car loan. In the end it will be better but really how much better? Is it worth the cost? In the end only you can answer that question. I have my answer.
If your arm base is anything like my older one, it is possible by rotating the pivot point about the mounting post (which has the dial for height on top) to move the pivot point towards or away from the record center. A 3 mm adjustment should be easily attained. This is all described in the VPI JMW-3D Printed Tonearm Manual on its page 5. Shown also is the adjustment jig that came with my arm to assure an exact position. Did you get one?
Alternatively you can toss your "arc" protractor and use any number of others that are equally as reliable and do not rely on a precise pivot to center measurement.
I guess I don't understand your reaction. You just spent nearly four thousand dollars on a defective turntable and the manufacturer told you to send it back so he could replace it with a good one. If that constitutes throwing the baby out with the bathwater, then I suggest you keep it and enjoy your defective turntable.To each his own!
Good luck,
John Elison
Edits: 11/23/15
John, what the hell is wrong with you. The arm base is mounted to a wood chassis using long wood screws, most likely what has happened is in shipping the base got hit by the solid foam we use to protect the table, and slightly rotated. I checked 7 Primes at the factory and every one was 258 or 259. but what do you care, just throw out the baby with the bath water, say VPI sucks and get back to measuring arc protractors!!!!!!!!
Let's be realistic here, UPS drops everything roughly 6 times before you get it, things happen, grow up.
HW
No need to fly off the handle again Harry. If you'd read one of John's responses to your recent posts you would most certainly see he doesn't think "VPI sucks".
A quote from John's response...
"I think your turntables represent an excellent value in today's marketplace, especially the new Prime. Two of my friends just bought the Prime and it sounds very good to me."
While I see both points I think the following picture describes the situation perfectly...
---
Regardless of what table you buy or own as long as you're spinning vinyl you're doing the right thing!
You too John..and everyone else. I am not math centric at all. I set up my VPI 3D with a Mint protractor very carefully...the included single point protractor from VPI confirms the exact same location. To ME...adjustment of azimuth properly made a very big difference.
On another point.... has anyone downloaded Dr. Feickert's app called PlatterSpeed? This seems like an accurate (or close to) measurement of platter rotation. You play a 3150 hz. test tone (on many test records) and it gives you the rotation by measuring pitch. FREE
The Mint Protractor is an arc protractor. These are the best kind of protractors in my opinion. I believe they are the easiest to use and provide the most accurate alignment.
Enjoy!
John Elison
Well, an arc protractor doesn't provide any more accuracy than other protractors. Tangency at two points is what it comes down to and other devices will get you to exactly the same settings. What is critical IMO is a mirrored surface to line up the cantilever more easily.
As for ease, that's a matter of opinion and I have a different one.
Moreover where an arc protractor may disappoint is that if your arm is not located at precisely the specified center to pivot distance, and it may be that few are, the arc protractor will give you a headache.
Personally I prefer a "point to the pivot" type of protractor. One protractor to rule them all---to work with any arm. No iterations. Set it and forget it. Inexpensive.
Happy Thanksgiving . . . now on to the turkey!
> Personally I prefer a "point to the pivot" type of protractor.
In my opinion, this type of protractor is the worst kind of protractor because it allows the greatest possibility for an erroneous alignment. It is virtually impossible to point the line exactly at the pivot and there is no way of confirming whether it's pointed accurately or not. Just the slightest pointing error will result in substantial null-point and overhang error without any way to double check the results.
The arc protractor, on the other hand, is the easiest to determine whether or not overhang is set correctly, especially when using a magnifying glass. Once the stylus traces the arc perfectly, you know beyond any shadow of a doubt that overhang is right on the button. Then you need only adjust offset to one of the two alignment grids. After that, you can easily recheck overhang to make sure the stylus still traces the arc exactly. The arc protractor provides complete assurance that your alignment is as accurate as humanly possible.
However, to each his own!
Happy Thanksgiving!
John Elison
Well, I've been pointing my Cart-a-lign to the pivot for many years without the problem John worries about. To make it, or a similar one like the Turntablebasics, even easier you can just tape some card stock to it and extend the pointing line to the pivot and then it wold be easy enough even for John to get exactly right. There are many other simple tricks.
As is said below, the Feikert type of protractor, or the VPI, easily allows for a perfect point. In the case of the VPI one it is just for their arms. Each of them could be improved, I think, with a mirror surface making it easier to align the cantilever.
John, I haven't the slightest doubt that with just a little practice you can do it, save yourself some money and be ready, without spending another dime, for that VPI 3D JMW arm attached to the VPI Prime that you covet.
> John, I haven't the slightest doubt that with just a little practice you can do it, save yourself some money...
I've done it and I fully understand the principle of the "point-to-the-pivot" type of protractor. However, my preference is for the arc protractor because it allows complete confirmation of the alignment. There are two null-point grids and the stylus/cantilever must line up at both simultaneously while holding the protractor stationary. You can also reconfirm overhang by rechecking that the stylus follows the arc exactly. I am fairly knowledgeable and experienced regarding cartridge alignment and I prefer the arc protractor over any other type of protractor I've used.
With regard to spending money, I prefer not to ! Therefore, I make my own arc protractors using Conrad Hoffman's Custom Arc Template Generator for Phono Cartridge Alignment . It is a free program you can download and it allows you to make sure the arc corresponds exactly with your tonearm's pivot-to-spindle mounting distance.
To each his own!
Best regards,
John Elison
thank you john e. for your suggestion about the printable protractors. i had a problem with my main cartridge the other day and put my back up zu denon on the arm, but in the past have had a feikert on long term loan that is now gone. i ordered a new one, but it won't be in until next week. so, in the meantime, i printed one for my arm and used it on my zu. the zu, like all denons is very hard to align because the stylus sits so far under the body, but with an old radio shack helping hands and bright flash light, i managed. the music was sorted out better and the bass tighter, so an improvement over eyeballing. luckily, from use of the past feikert, i knew the spindle to pivot distance was 299 mm. once you have that number, the program is simple. thanks again.
Tom Collins
You're Welcome!
One thing you should be aware of when using Feickert's Protractor is that the two alignment null-point grids are offset from each other by a fixed angle. This angle corresponds to one specific effective length tonearm only. Therefore, unless your particular tonearm has the unique effective length corresponding to Feickert's null-point grid offset angle, you will need to reposition the protractor when checking between Step 2 and Step 3. In other words, Feickert's protractor is not an arc protractor although the alignment grids are laid out on an arc. That arc will be valid for one specific length tonearm only. Consequently, after setting cartridge offset at Step 2, it is perfectly okay to reposition the protractor when rechecking cartridge offset at Step 3.
I couldn't find any mention of the actual null-point radii used by Feickert's Universal Protractor. Normally, when we think of Baerwald (Lofgren A) we think of null-points of 66-mm and 120.9-mm, but those are only valid for the IEC modulated groove envelope with innermost groove at 60.325-mm and outermost groove at 146.05-mm. You might want to measure the distance on Feickert's protractor from the spindle hole to the "B" null-point lines at Step 2 and Step 3 just to confirm the null points are in fact 66-mm and 120.9-mm.
Anyway, it will be interesting to find out how closely the alignment achieved with Feickert's protractor corresponds with Conrad Hoffman's arc protractor.
Good luck,
John Elison
Yes. I was thinking the same. Could send it back I suppose.
Tom Collins
the Feikert works very well and is easy to set up to assure accuracy.
Tom Collins
for him measurements are measurements and numbers don't lie.
He has the schematics to prove it!
There are NO exceptions, dammit!
"Once this was all Black Plasma and Imagination" -Michael McClure
There is nothing defective about it at all. It is a matter of using a protractor that matches the actual distance between the two points. And, as I pointed out in my reply to Harry, the actual difference turned out to be very minor and not audible. Like you said, to each his own.
> Like you said, to each his own.
Here's another good one:
"You can lead a horse to water but you can't make him drink." ;-)
How many times do I have to say that the insanity in this business over arc protractors and alignment is total nonsense designed to sell arc protractors and make customers afraid of setting up there turntables.
This is a very simple process requiring no more than 15 minutes of setup time and a good pair of glasses. The spindle to pivot distance is irrelevant to anyone who has actually set up a few thousand cartridges and has heard what those differences actually are sonically. I align the cantilever, not the cartridge, not the cartridge location.,
This is no different than a doctor telling you your pressure is high but not giving you the numbers, he keeps you in the dark so he has all the answers and you need him more than you actually do. COME ON VINYL LOVERS, YOU CAN DO IT YOURSELF, YOU DO NOT NEED EXPERTS TO SET UP A TONEARM. Watch the VPI videos and you will get it 99% right.
HW
> How many times do I have to say that the insanity in this business over arc protractors and alignment is total
> nonsense designed to sell arc protractors and make customers afraid of setting up there turntables.I don't believe I've ever heard you say that before. The last thing you said in this thread that I remember is:
> You can print out arc protractors for any spindle to pivot distance and get your alignment perfect that way.
Of course, this is only true when the tonearm is mounted at the proper distance from the spindle relative to its effective length.
Here is another statement that you wrote in this thread:
> The spindle to pivot distance is irrelevant to anyone who has actually set up a few thousand cartridges
I don't know where you get these ideas, but they demonstrate a serious lack of understanding regarding tonearm alignment geometry.
Let's talk about the tonearm parameters you published on your webpage for the JMW 10-3D tonearm . I believe this is the tonearm you provide with the Prime turntable. Correct me if I'm wrong.
The following three parameters define a unique null-point alignment geometry:
Pivot-to-spindle = 258-mm
Effective length = 273.4-mm
Offset angle = 19.98-degreesThe alignment null-points for the tonearm parameters above are:
Inner Null-Point = 70.1-mm
Outer Null-Point = 116.7-mmThis alignment reduces tracking error distortion in-between the null-points by allowing higher distortion to occur in the inner and outer groove areas. It is commonly know as Lofgren's "B" alignment as represented by the following graph.
Now, the protractor you provide with your Prime turntable is designed for a different null-point alignment. I measured the inner null-point directly from the protractor to be about 66-mm. Then, I calculated the outer null-point using Seb's Equation to be about 121-mm. I'm confused as to why you stipulate one alignment on your webpage and yet the protractor you provide with your Prime turntable is designed for a different alignment. Can you explain this discrepancy?
Thanks,
John Elison
Edits: 11/24/15
Is it?
Runs away laughing and bouncing like Daffy.
100%!
"Once this was all Black Plasma and Imagination" -Michael McClure
.
What you might try doing is loosen the arm base mounting screws, the arm base has quite a bit a free motion before tightening down and we set it for 258 +/- 1 mm. It could have been moved in shipping. Having seen the adjustment range of the arm base I think you can get to where you want to be or much closer than now. While I doubt you will hear a difference you will feel better.
Making the Avenger with multiple arms and rotating arm boards has shown me the actual distance is less critical then you knowing what it is and compensating for it. You can print out arc protractors for any spindle to pivot distance and get your alignment perfect that way.
I know I make Fremer and probably John crazy when I say these things but I hear a much greater difference getting azimuth, SRA, and VTF spot on then the overall lateral alignment. I can play with the overhang and spindle to pivot distance all day and hear almost no difference as long as I am relatively close. You're just moving where the null points are and where you like your distortion to set in and how much, a no win game. Then again I don't use anti-skate which makes other people crazy!!
BTW, if you play a lot of classical the Stevensen method sounds the best!!!
Enjoy your Prime and play music, not math.
HW
I should have read your post yesterday. Yesterday I played with tracking using an Accu-Trac protractor. First I checked to see how far off my cartridge was as it was set with a 258 mm protractor. A very small amount, perhaps the thickness of the line outside the arc on the inner part. Two hours later it was spot on. If that much difference matters I can't hear it. Then I redid the alignment using the Stevenson method because that is what I used for years and because it was a rainy day anyway. The Stevenson method sounds better on the inner most part of the record where the grand finale on many classical pieces is found. Otherwise, for jazz and classical the Baerwald sounds a wee bit better. Not a big deal either way. I agree with you about azimuth and VTF as being more important. Personally, I think a bigger difference than any of this is getting the speed stable with either an SDS or the Phoenix Engineering stuff. That is my opinion anyway and I am sticking with it.
You are spot on and it is about time for customers to understand this is not a on off game, there are a million ways to mount a cartridge correctly.
I love Tony Cordesman's comments to me years ago about alignment,"Since the hole is not in the center which side are you aligning for!!!"
> You can print out arc protractors for any spindle to pivot distance and get your alignment perfect that way.> I know I make Fremer and probably John crazy when I say these things...
Tonearm effective length and pivot-to-spindle distance must be matched to each other in order to achieve proper alignment. When you increase pivot-to-spindle mounting distance you also need to increase tonearm effective length. The headshell slots will allow for only small errors in pivot-to-spindle distance because their main purpose is to accommodate cartridges with different stylus-to-mounting-hole dimensions not gross errors in pivot-to-spindle distance. Whether or not you can hear the increased distortion resulting from cartridge misalignment does not alter the facts regarding tonearm alignment geometry.
I think your turntables represent an excellent value in today's marketplace, especially the new Prime. Two of my friends just bought the Prime and it sounds very good to me.
Best regards,
John Elison
Edits: 11/22/15
The effective tonearm length was increased using the slots, with much room to spare. A protractor for the actual distance was used. All is well.
"..if you play a lot of classical the Stevensen method sounds the best!!!"
Wow, HW; can you elaborate? Classical is about all I listen to.
Forget about 'Çlassical Music'. If you listen to records of any genre and you don't want to suffer the vagaries of alignments and anti-skate, you move to the best linear tracking arm you can afford and align the cartridge as closely as you can to radial tracking. That is also not perfect and carries its own set of compromises but with a great linear tracker and accurate alignment to the radius of the record it disposes of a raft of troubling problems that only arise with the pivoting arm.
Edits: 07/31/16
I don't mean to put words in HW's mouth, but in the event he doesn't reply, I'll take a stab at your question.
In a lot of classical music, the loudest, most complex passages occur at the end of a composition. These are the most demanding in terms of the stylus tracking the grooves. This means these complex, demanding passages occur in the innermost grooves of an LP side. The Stevenson alignment, if I understand it correctly, places the inner null point (which is one of the points of the least distortion) closer to the innermost grooves of an LP side. Hence, you get lower distortion in the areas where the most complex music occurs.
I hope this is decently close, but if not, perhaps someone (HW if possible) will elaborate.
-Bob
Many pieces have their loudest parts within a movement, and not toward the beginning or end.
Many do. But I would say that MOST classical works are more likely to have loud passages at the end. Maybe not THE very loudest passages, but certainly loud ones. Of course, as with all generalizations, this is not universally true. If you Google "Stevenson alignment classical music" you will see that this theory is not mine alone, for instance at the link below. Again, I have no idea whether or not this is why HW made his statement, but I do think it stands up to reason.
-Bob
Now I wonder if Stevensen wrote a paper on the subject....
Hi Steve,
Did you check the Vinyl FAQ?
... Peter Ledermann and you must have had interesting conversations when he came up with the original "VPI Zephyr" (I have one, on a 10.5i).
Edits: 11/21/15
We have had a few, he is very much into the engineering side while I on the other hand have decided that like rich women's faces, what a million years of evolution gave you is only a recommendation.
HW
Interesting comment about evolution and "rich women's faces." I'm still trying to figure it out.
rich women's faces frequently attempt to defy evolution and natural, graceful aging through
the help of that financial richness and (usually a not very capable) plastic surgeon.
In other words, tweaking.
There are exceptions as with most things in this wonderful life.
"Once this was all Black Plasma and Imagination" -Michael McClure
Ah, that makes sense. Thanks. I wonder how long it would have taken me to figure that out.
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