Sometimes that depends on the design of the arm. Here is a classic article to take a look at. I haven't done the math for a 10.5 in arm so I'm not sure as to what the angle should be.
http://www.helices.org/auDio/turnTable/stevenson.pdf
According to Fig 6b it looks as if 19 degrees is bang on for a 10.5 inch arm - but hey - I'm a big dummy - just ask ZM.
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Yeah - but then I am an old dude now!!!!
(And I'm grateful for every day that I get to hang around here and learn some new tricks. )
Yeah - but then I am an old dude now!!!!
I'm not much younger!
Regards zeoN_Rider
I am just going by this for the angle of the cartridge http://welltemperedlab.files.wordpress.com/2009/02/wtl-headshell-alignment-guide.pdf
long arm
I wonder how a really, really long arm would work.
Possibly in the range of 25 to 35 inches.
By theory tracking error at the center null point (using Boerwald) should go down drastically if the present idea that a shorter arm makes the null point error increase drastically.
The technology is there as seen by these great pics.
Paul
I wonder how a really, really long arm would work.
Possibly in the range of 25 to 35 inches.
By theory tracking error at the center null point (using Boerwald) should go down drastically if the present idea that a shorter arm makes the null point error increase drastically.
The technology is there as seen by these great pics.
Paul
uni-pivot
Really a different animal. I never had a uni but remember the old Stanton or Pick. that was a uni.
My arm is just plain bearings that I replaced with DIY bearings due to age.
The arm is very rigid.
I have often thought about trying to make a uni. but was very happy with the fact that I finally got my ROK arm up and running. It took 25 years until I had time.
If I did a uni. I would make it very much longer. I remember making a uni. way back in the 50's but I didn't know it was a uni.
I use wood and it was 48" long with a GE VR II mono cart. The arm sounded as good as an untrained ear can manage. I didn't have the knowledge at the time being in high school and gave up due to issues.
Over the years being a certified journeyman tool & diemaker my knowledge level is pretty broad and being retired gives me the time.
I recently connected with a machinist(hobby) that has a full machine shop. 2 big lathes and 2 Bridgeport milling machines at his house. He has much equipment but limited practical machine knowledge. He just loves working on the machines. I am working on a uni. idea that would require the use of his mill and lathe.
Plans are for after the first of the year as he is also retired and travels a lot.
Paul
Really a different animal. I never had a uni but remember the old Stanton or Pick. that was a uni.
My arm is just plain bearings that I replaced with DIY bearings due to age.
The arm is very rigid.
I have often thought about trying to make a uni. but was very happy with the fact that I finally got my ROK arm up and running. It took 25 years until I had time.
If I did a uni. I would make it very much longer. I remember making a uni. way back in the 50's but I didn't know it was a uni.
I use wood and it was 48" long with a GE VR II mono cart. The arm sounded as good as an untrained ear can manage. I didn't have the knowledge at the time being in high school and gave up due to issues.
Over the years being a certified journeyman tool & diemaker my knowledge level is pretty broad and being retired gives me the time.
I recently connected with a machinist(hobby) that has a full machine shop. 2 big lathes and 2 Bridgeport milling machines at his house. He has much equipment but limited practical machine knowledge. He just loves working on the machines. I am working on a uni. idea that would require the use of his mill and lathe.
Plans are for after the first of the year as he is also retired and travels a lot.
Paul
Wow, an arm thread I haven't seen yet!
madmike46: The arm looks very good, nice construction.
pdm4606: Tracking error does go down significantly as length increases. Firebaugh apparently limited the arms to 10.5 as a "practical limit" to fit most tables. It makes sense. A 12" effective length arm sits 3" further away from the spindle than a 9" (go figure). The best possibility is an infinitely long arm, but alas beyond practical application. 2nd place is a good linear tracker (I don't own an LT of any sort). Next a good pivoting arm of a practically long fixed length. I've seen photos of 25"+ arms but they can only exist where kids (or pets or spouses) can't. After 12" or so there are diminishing returns...
madmike46: The arm looks very good, nice construction.
pdm4606: Tracking error does go down significantly as length increases. Firebaugh apparently limited the arms to 10.5 as a "practical limit" to fit most tables. It makes sense. A 12" effective length arm sits 3" further away from the spindle than a 9" (go figure). The best possibility is an infinitely long arm, but alas beyond practical application. 2nd place is a good linear tracker (I don't own an LT of any sort). Next a good pivoting arm of a practically long fixed length. I've seen photos of 25"+ arms but they can only exist where kids (or pets or spouses) can't. After 12" or so there are diminishing returns...
Not much has happened in the last while, had another turntable to repair for a friend, a Thorens TD-320 MkII with broken suspension parts. So I have been playing with that for awhile now. With summer here there won't be much happening till fall again.
I was at a trade show for CAD/CAM software and one of the software companies was running their software on Cray supercomputers back in the mid 90's and gave away Cray golf balls as part of the promotion. I got about a dozen. I could sell one of those to you but then it would be a digital tone arm I suppose.
I was at a trade show for CAD/CAM software and one of the software companies was running their software on Cray supercomputers back in the mid 90's and gave away Cray golf balls as part of the promotion. I got about a dozen. I could sell one of those to you but then it would be a digital tone arm I suppose.
The really big Cray's used to be liquid cooled too - this could pose a problem.....
The really big Cray's used to be liquid cooled too - this could pose a problem.....
Since it's a really fast computer it may only work with 1,000,033.33 RPM records too.
The really big Cray's used to be liquid cooled too - this could pose a problem.....
not really! Silicon damping fluid has very good thermal properties (good enough to resist automotive brake temperatures, good enough for a processor (or tonearm ).
I am considering making a DIT WTB for a friend using 2" wood dowelling for the tower and the tonearm rest. Having listened to my DIY 219 for several years now, I still cannot imagine a DIY WTL tonearm bettering it, but I am willing to concede that the WTL may be better. But unless the WTL is clearly superior to a SME 309 (or a Linn Akito II or a hotrodded Rega RB300) I won't be holding my breath.
The benefit of the 219 compared to the DIY WTL is that there are much fewer steps in making a 219 than a WTL. Almost everything else is similar between the two tonearms (I detest carbon fibre, so I used good old Easton aluminium arrow shafts). Really the only physical differences are the pivot details: bearing and cup based unipivot vs fluid damped ball unipivot. The main differences are the need to have access to some good machining vs. the "kitchen table" approach. If one had to pay to have machining done, I know the 219 would have the addition of a budgetary advantage.
madmike46: Please know that this post is not intended to be argumentative or to say that the WTB cannot compete with the 219, but more so to point out that the 219 is a "kitchen table" design and build. Nor is it intended to take away anything from your very impressive build. Your DIY WTL looks to be finished to a very high degree, and should certainly sound excellent (which I am sure it does).
not really! Silicon damping fluid has very good thermal properties (good enough to resist automotive brake temperatures, good enough for a processor (or tonearm
). I am considering making a DIT WTB for a friend using 2" wood dowelling for the tower and the tonearm rest. Having listened to my DIY 219 for several years now, I still cannot imagine a DIY WTL tonearm bettering it, but I am willing to concede that the WTL may be better. But unless the WTL is clearly superior to a SME 309 (or a Linn Akito II or a hotrodded Rega RB300) I won't be holding my breath.
The benefit of the 219 compared to the DIY WTL is that there are much fewer steps in making a 219 than a WTL. Almost everything else is similar between the two tonearms (I detest carbon fibre, so I used good old Easton aluminium arrow shafts). Really the only physical differences are the pivot details: bearing and cup based unipivot vs fluid damped ball unipivot. The main differences are the need to have access to some good machining vs. the "kitchen table" approach. If one had to pay to have machining done, I know the 219 would have the addition of a budgetary advantage.
madmike46: Please know that this post is not intended to be argumentative or to say that the WTB cannot compete with the 219, but more so to point out that the 219 is a "kitchen table" design and build. Nor is it intended to take away anything from your very impressive build. Your DIY WTL looks to be finished to a very high degree, and should certainly sound excellent (which I am sure it does).
not really! Silicon damping fluid has very good thermal properties (good enough to resist automotive brake temperatures, good enough for a processor (or tonearm
I am considering making a DIT WTB for a friend using 2" wood dowelling for the tower and the tonearm rest. Having listened to my DIY 219 for several years now, I still cannot imagine a DIY WTL tonearm bettering it, but I am willing to concede that the WTL may be better. But unless the WTL is clearly superior to a SME 309 (or a Linn Akito II or a hotrodded Rega RB300) I won't be holding my breath.
The benefit of the 219 compared to the DIY WTL is that there are much fewer steps in making a 219 than a WTL. Almost everything else is similar between the two tonearms (I detest carbon fibre, so I used good old Easton aluminium arrow shafts). Really the only physical differences are the pivot details: bearing and cup based unipivot vs fluid damped ball unipivot. The main differences are the need to have access to some good machining vs. the "kitchen table" approach. If one had to pay to have machining done, I know the 219 would have the addition of a budgetary advantage.
madmike46: Please know that this post is not intended to be argumentative or to say that the WTB cannot compete with the 219, but more so to point out that the 219 is a "kitchen table" design and build. Nor is it intended to take away anything from your very impressive build. Your DIY WTL looks to be finished to a very high degree, and should certainly sound excellent (which I am sure it does).
Thanks for the kind words Nanook. Being a machinist is why I went to the WTL design, I have been looking at your thread on the 219, that is a very simple arm, I might have to try one like it later on.
The only advantage of the WTL would be motor noise isolation. So if your motor vibrates then you would notice a difference. The other option is to isolate the motor itself. I agree with Nanook in choosing aluminum over carbon for the arm itself. Carbon likes to Obsorb energy, so if you combine it with a low mass cartridge you will end up deteriorating the signal.
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