Hi Colin,
Just a few words about last night's session. Spent a good couple of hours listening to and enjoying some of my favourite records. Got some back of neck hairs standing up too. Did a few quick checks on ringing/taping etc. With my 4 tube prototype I can easily get directly under the stationary rail and rap it with my finger or a pencil. With the stylus on a nonrotating record ant the gain set at almost full up all this arm gives is a soft dull thud and none of the ringing I was fighting with previous designs. Earlier designs were functioning as sensitive microphones picking up for miles around. This new design has none of those problems and uses none of the techniques I was trying to control the problem. As shown in my picture the carriage was a bit too sensitive to external forces knocking the moveable rail off the track. Last night I added 10grams just above the arm mounting bracket. That anchors the carriage very well. Colin, if you make the tubes long enough so that the center of the carriage tubes remains well within the space between the 2 balls there is no problem with one ball getting weighed down and the other becoming unloaded. Add as little as 10 grams to the carriage tube just over the line of the arm wand and all remains firmly anchored. Also running the arm from end of record to beginning with no arm lift becomes very easy and stable. Nothing precarious in the system at all. So far I have not seen or heard any change in sound with any of the mods I've been making. I'm sure you will hear a difference from one cart to another but that is about the limit. This arm will imho make an excellent tool for evaluating cartridges.
Got to make a pretty one now.
Chris, You done good!!
BillG
cool !!!
I tried glass for the bottom rail using the "TV antenna carriage " for the upper part, it worked very well but the glass rods that I found were too big so I returned to the antenna rods, glass can have a very smooth surface so that is desirable just make sure the rods are straight, for the upper carriage glass could be too heavy for the cartridge so I would go with other material as long as they have a smooth surface to get the full potential of the arm with low friction in all planes, I think for the wand I would go with the carbon tubing first for in principle they should be more rigid .
(yes those are pipettes)
Bill,
Sounds like an arm that works very well in your system
, I am going to be building one of my own since I've taken my other Linear tracker as far as it can go. I haven't had microphonics issues but that can also come down to being a different base and coupling arrangement altogether.
Soyuz idea does work well provided the balls are initially arranged properly, I have used long tubes and as best as I can see it works best if the wand is centered with the balls at the middle of the lp, that is the only con in user friendliness I can see. I look forward to giving it a spin too, and with a little elbow grease we can expand on this idea further.
Colin
Sounds like an arm that works very well in your system
, I am going to be building one of my own since I've taken my other Linear tracker as far as it can go. I haven't had microphonics issues but that can also come down to being a different base and coupling arrangement altogether. Soyuz idea does work well provided the balls are initially arranged properly, I have used long tubes and as best as I can see it works best if the wand is centered with the balls at the middle of the lp, that is the only con in user friendliness I can see. I look forward to giving it a spin too, and with a little elbow grease we can expand on this idea further
.Colin
Hi Chris.
That's a really elegant arm you've made, both visually and in terms of engineering. This must be the simplest arm design ever, and there's a lot to be said for keeping things simple. I think Colin's design of square headshell and low slung triangular counterweight would work really well on this arm, both sonically and aesthetically. I might be tempted, looking at your photo, to make an arm with twin arm pillars, one at either end of the long rail. But then I might just have German blood in my veins as I seem to share this nation's love of over-engineering.
Niffy
That's a really elegant arm you've made, both visually and in terms of engineering. This must be the simplest arm design ever, and there's a lot to be said for keeping things simple. I think Colin's design of square headshell and low slung triangular counterweight would work really well on this arm, both sonically and aesthetically. I might be tempted, looking at your photo, to make an arm with twin arm pillars, one at either end of the long rail. But then I might just have German blood in my veins as I seem to share this nation's love of over-engineering.
Niffy
Arm Up[ and Running!
Guess what Guys? It works! And it works excellently! I still need to adjust it properly and ensure that arm height, geometry etc are all correct, but I couldn't resist just trying it out.
Only one downside- I lost a ball (!?) when adjusting it on the deck-thank goodness the 10 I had ordered from EBay arrived this morning. However, once set up I don't think I'll be having any more losses (fingers crossed)
Chris
Guess what Guys? It works! And it works excellently! I still need to adjust it properly and ensure that arm height, geometry etc are all correct, but I couldn't resist just trying it out.
- Tracking-very smooth and sure footed. It moves so much more smoothly and easily than with the ball races. The tracking weight is also much easier to adjust as 'up-down' pivot motion is much free-er (!)
- Bass is excellent-immediately noticeable after a couple of bars.
- Stereo imagery is improved and images are more solid.
- This arm has a lot going for it
Only one downside- I lost a ball (!?) when adjusting it on the deck-thank goodness the 10 I had ordered from EBay arrived this morning. However, once set up I don't think I'll be having any more losses (fingers crossed)
Chris
Attachments
Thank you.
I'm home next weekend. and have gathered all the parts.
Looking forward to giving this arm a go.
Maybe my results are.the varied
Rigged up a version of this using 6mm glass tubes and 4mm balls , there is a weight limit definitely to how heavy you can have the top tubes. Surprisingly enough contrary to what I would have thought the lateral friction is not lower than my radial bearings and with the added weight of the sliding mass on off center records I am noticing the cantilever skewing as it stops the added mass to swing the opposing direction . Perhaps I'm in the minority here but if anyone else would play an off center record and watch the stylus it would be much appreciated.
Colin
Rigged up a version of this using 6mm glass tubes and 4mm balls , there is a weight limit definitely to how heavy you can have the top tubes. Surprisingly enough contrary to what I would have thought the lateral friction is not lower than my radial bearings and with the added weight of the sliding mass on off center records I am noticing the cantilever skewing as it stops the added mass to swing the opposing direction . Perhaps I'm in the minority here but if anyone else would play an off center record and watch the stylus it would be much appreciated
.Colin
but if anyone else would play an off center record and watch the stylus it would be much appreciated
in my case the cantilever/stylus does not "struggle" trying to follow the groove.
I've made a little video of my tonearm playing a 45 deliberately placed off-center(very), I don't have a 33 LP with enough eccentricity to be "worthy" of filming, the video camera its not good for macro so I did the old trick of adding an extra lens in front of it, its not excellent but at least it's something, it also shows the overall functioning of the arm :
https://www.youtube.com/watch?v=r-YXrJY5KB0&feature=youtu.be
Maybe my results are.the varied
Rigged up a version of this using 6mm glass tubes and 4mm balls , there is a weight limit definitely to how heavy you can have the top tubes. Surprisingly enough contrary to what I would have thought the lateral friction is not lower than my radial bearings and with the added weight of the sliding mass on off center records I am noticing the cantilever skewing as it stops the added mass to swing the opposing direction . Perhaps I'm in the minority here but if anyone else would play an off center record and watch the stylus it would be much appreciated
Colin
Hi Colin, I took an old record and dragged the center hole about 1/4" or a bit more from center. Gave the arm a good workout. I will have to remount the 2 tube arm and check it for comparison. Can't say I saw much. The old record was a well played mono recording and just watching the stylus it seemed to not be as smooth. Shifting the record back to center didn't make any obvious difference. I think there was a very small stylus skewing that was barely synchronized to the direction of arm motion but it was not consistent and barely visible. Taking my added 10 gram weight off the carriage tubes didn't show much either. I got the feeling it was not as good as the unweighted version but again very hard to see. Prior to making the test I removed the top tubes and checked the rolling balls to verify level and unimpeded motion. Someone else please check this out.
Rgds,
BillG
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When I was testing my original bearings I knocked up a simple test rig to test relative bearing friction, as your arms have the centre of mass well below the pivot this should be very simple to try. With the rail set perfectly horizontal balance the arm so that it has zero down force. Then using a cat's whisker try and push the carriage from side to side. Look at how far the whisker bends before the carriage starts to move. It's a good idea to cut the whiskers tip off so you can more easily ensure that you are using exactly the same length of whisker for subsequent tests. If you don't have a cat a bristle from a soft brush will do. This test is much easier than trying to see a microscopic cantilever movement on a moving record.
Niffy
P.s. I did use a naturally shed whisker.
Niffy
P.s. I did use a naturally shed whisker.
Lateral Friction
Maybe my results are.the varied
Rigged up a version of this using 6mm glass tubes and 4mm balls , there is a weight limit definitely to how heavy you can have the top tubes. Surprisingly enough contrary to what I would have thought the lateral friction is not lower than my radial bearings and with the added weight of the sliding mass on off center records I am noticing the cantilever skewing as it stops the added mass to swing the opposing direction . Perhaps I'm in the minority here but if anyone else would play an off center record and watch the stylus it would be much appreciated
Hi Colin
I'm surprised about your comment concerning lateral friction-On mine I have found it significantly less-and I don't believe I had poor ball races on the other arm which worked very well. However, my carriage (top tubes and arm) only weighs in at 12g anyway and glides across very easily indeed.
Chris
Colin
Chris,
Have been working away at it tonight, still not getting anywhere near the results of ball races I have here even with Niffys cats whisker. You would be surprised of the differences between ball races, there are good and then phenomenal. This concept is just a very stripped down straightened ball race sans cage with 2 vs 10 bearings so should work similarity in theory. My experience and your 12g lateral tells me this is suited to higher compliance cartridges and higher loading increases the friction. Soyuz, what is your arms total weight?
Colin
Have been working away at it tonight, still not getting anywhere near the results of ball races I have here even with Niffys cats whisker. You would be surprised of the differences between ball races, there are good and then phenomenal. This concept is just a very stripped down straightened ball race sans cage with 2 vs 10 bearings so should work similarity in theory. My experience and your 12g lateral tells me this is suited to higher compliance cartridges and higher loading increases the friction. Soyuz, what is your arms total weight?
Colin
Hi Colin
Haven't tried the cat's whisker (our dog ensures no cats ever get near our place!) More experimentation is needed but either way, both designs provide the goods in my experience. One comment-someone mentioned the Cantus as being a reference. As you know, I am one of the few people on these threads who seems to have owned one- and I can categorically state that both these designs outperform it by a considerable margin.
Chris
Haven't tried the cat's whisker (our dog ensures no cats ever get near our place!) More experimentation is needed but either way, both designs provide the goods in my experience. One comment-someone mentioned the Cantus as being a reference. As you know, I am one of the few people on these threads who seems to have owned one- and I can categorically state that both these designs outperform it by a considerable margin.
Chris
I think that was my comment, it's my "platonic" reference
I'm glad to read your impressions of the other tonearms compared to the original Cantus.
17.52 grams including the cartridge (shure m97 with SAS).
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