Yes I have that also, not yet used the app.
I have the full Adjust+ suite, and the graphs I showed before are made with that.
Jan
@Mark Whitney,
A very nice video (Nakamichi Dragon)! Nevertheless, I wonder about the correcting system. The small pin has to “feel” the brim of the record and next it pushes just the dimension of the eccentricity. The video shows more than one attempt. Probably because not all the records are a perfect circle at the brim.
@billshurv,
Imagine the V-shape of the groove and the stylus within the groove. Fixed pivot tonearms are rigid constructions. So they force the stylus all the way from the outside to the inner side of the record. Fixed pivot tonearms has a lot of mass too (counterweight, horizontal or vertical bearing). The stylus of a cartridge tries to align itself at right angles to the spindle (average friction at both sides of the tip of the stylus). But that’s impossible because of the rigid construction. As a result the stylus is “scraping” through the groove (unwanted vibrations). That is not the way it has to be (don’t shoot the messenger).
When you use a laser to detect the eccentricity of vinyl records, you will discover that nearly all your records have an eccentricity that’s more than the distance between 2 adjacent grooves (> 0,1 mm). So the mass of the tonearm is moving to and fro all along the trajectory. Now think about the scraping stylus...
@jan.didden,
So you has bought the PC application (399 euro)? I am glad I haven’t a rigid tonearm... (that's really an expensive "tool")
A very nice video (Nakamichi Dragon)! Nevertheless, I wonder about the correcting system. The small pin has to “feel” the brim of the record and next it pushes just the dimension of the eccentricity. The video shows more than one attempt. Probably because not all the records are a perfect circle at the brim.
@billshurv,
Imagine the V-shape of the groove and the stylus within the groove. Fixed pivot tonearms are rigid constructions. So they force the stylus all the way from the outside to the inner side of the record. Fixed pivot tonearms has a lot of mass too (counterweight, horizontal or vertical bearing). The stylus of a cartridge tries to align itself at right angles to the spindle (average friction at both sides of the tip of the stylus). But that’s impossible because of the rigid construction. As a result the stylus is “scraping” through the groove (unwanted vibrations). That is not the way it has to be (don’t shoot the messenger).
When you use a laser to detect the eccentricity of vinyl records, you will discover that nearly all your records have an eccentricity that’s more than the distance between 2 adjacent grooves (> 0,1 mm). So the mass of the tonearm is moving to and fro all along the trajectory. Now think about the scraping stylus...
@jan.didden,
So you has bought the PC application (399 euro)? I am glad I haven’t a rigid tonearm... (that's really an expensive "tool")
Also, centering the record at the rim is no guarantee that the grooves are centered; the rim may be different from the hole as well.
Jan
Its not centering the record at the rim, but on the edge of the glass platter, and the reference is the outrun groove. Its kinda like balancing the tires on your vehicle at the garage. The table "knows" where to stop the platter, and how far it needs to "nudge" the platter.
Steen
I got into vinyl seriously in 1984. Even back then people were arguing between linear and pivoted arms (and the well tempered arm was on the horizon). Back then the general consensus was that the drawbacks (long arm, linear bearing problems etc) usually were greater than the benefits. I love my SME arm, and doubt a pivoted arm could get much better, at least for less than stupid money. If you have fixed the problems with linear trackers then I take my hat off to you and will read up on that with interest.
I do have a kenwood KD550 that at some stage will become my second table. I may have some fun with that...
@sreten,
“Try what?” Well, your idea about an eccentric spindle! You can draw an eccentric circle (spindle) and use a pin to rotate “the eccentric spindle”. After that, you make a bigger eccentric circle that fits arond the spindle and that’s the record. Now you can try to eliminate the eccentricity of this “record” by rotating the spindle.
@billshurv,
Read this description of a low cost high end linear tonearm (about 50 euro).
“Try what?” Well, your idea about an eccentric spindle! You can draw an eccentric circle (spindle) and use a pin to rotate “the eccentric spindle”. After that, you make a bigger eccentric circle that fits arond the spindle and that’s the record. Now you can try to eliminate the eccentricity of this “record” by rotating the spindle.
@billshurv,
Read this description of a low cost high end linear tonearm (about 50 euro).
Interesting. I need to mull over that concept. How would one test that to demonstrate if it is actually superior to a std 9" pivoting arm like most of us use?
@billshurv,
I have tested the tonearm with a testrecord. Every track is played back flawlessly. But more important: you hear a noticeable difference in relation to your old tonearm. And... unmodulated parts of the groove are entirely silent (like a CD). There are no 9, 10, 11, etc. Hz resonances of the armtube too.
I have tested the tonearm with a testrecord. Every track is played back flawlessly. But more important: you hear a noticeable difference in relation to your old tonearm. And... unmodulated parts of the groove are entirely silent (like a CD). There are no 9, 10, 11, etc. Hz resonances of the armtube too.
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which test record? I am interested as I have test records but never really use them. Hell I even have the cardas degaussing record somewhere from my silly days. But I do know that my arm and cartridge sails through the telarc 1812, so tracking is not an issue on any real world modulation I am likely to find.
My unmodulated grooves are also silent.
Ref resonances, you will have some. Any tube will resonate at some point. just may be low level. I will dig out my test record for laughs. will be interesting to test. I've been happy with my arm for over 20 years now, but interested to know if there is even a step above.
For now I need to do some research as I have forgotten a lot of mechanics over the years...
My unmodulated grooves are also silent.
Ref resonances, you will have some. Any tube will resonate at some point. just may be low level. I will dig out my test record for laughs. will be interesting to test. I've been happy with my arm for over 20 years now, but interested to know if there is even a step above.
For now I need to do some research as I have forgotten a lot of mechanics over the years...
Hi,
That shows you didn't understand my post.
The spindle is variably eccentric. It works.
Think of two circles above each other but
joined via a pin that is a little off centre,
i.e. the pin, not the spindle is eccentric.
Also add another pin and a curved slot
in the top that limits the top rotation to
180 degrees and gives a return to zero.
Then reread my post, I'm getting NIHS.
rgds, sreten.
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@sreten,
I cannot find the word "variable" in your original post (#50). Maybe you can post a drawing that shows your idea?
There is one more problem: you cannot exchange the modification of the records by the modification of the turntable. So your solution has to work well without a new spindle/platter bearing.
I cannot find the word "variable" in your original post (#50). Maybe you can post a drawing that shows your idea?
There is one more problem: you cannot exchange the modification of the records by the modification of the turntable. So your solution has to work well without a new spindle/platter bearing.
Design a motorized method of positioning the record and a laser or microscope to measure the movement of the arm.
Design an active system where the eccentricity can be monitored and reduced while playing the record.
Design an active system where the eccentricity can be monitored and reduced while playing the record.
@ALL,
Well, I have to think about it. Because it is much easier to put the record over an enlarged spindle that's already set to compensate for the excentricity of the record.
Moreover, the Nakamichi needs a lot of time to centre each record. Maybe it is possible to reduce this action to nearly 2 seconds. But I have to do some mathematics "to fiddle with it".
Well, I have to think about it. Because it is much easier to put the record over an enlarged spindle that's already set to compensate for the excentricity of the record.
Moreover, the Nakamichi needs a lot of time to centre each record. Maybe it is possible to reduce this action to nearly 2 seconds. But I have to do some mathematics "to fiddle with it".
The Nakamichi does a pre positioning and only at the lead out groove. I am suggesting an active system which works continuously during playback and measures at the play area.
what would the benefit of that be? the eccentricity does not vary across the play area.
I suggested a low-tech solution with a simple adjustable plate, this was rejected, so I came up with a high-tech user friendly design.
Don't enlarge the center hole of your records. Replace the spindle to a smaller diameter one (6.8 mm to 7.0 mm) and move the record to and fro until it is centered. For "perfect" records, use a removable thin walled tube with OD 7.15 mm on the new spindle. For Linn owners, use the standard 7.15 mm removable spindle for good records, and machine another smaller diameter for bad records.
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