Moray,
Good post! I just want to make it clear that I'm only trying to get around the problem I'm having with trying to establish a given VTF. As far as playing warps and eccentricity in records goes, my Cantus with the glass V track gives no trouble. None of my records have more than small warps and next to no runout. So what am I complaining about? I would like to have the little Ortofon VTF balance able to show me what that force is. I have to carefully place the stylus on the balance and tap it and jiggle it and try to see that the position of the bearings in the V isn't biasing the VTF. To me it appears that the only true VTF is achieved under the dynamic condition of playing a record. Even if the inner ball race is positioned well within the radial free play range of that bearing, we still have the starting torque relative to the running torque of the bearing confusing the reading. Unfortunately the only observable indication of VTF is the amount of vertical deflection of the stylus cantilever with the record being played. IIRC Bo's setup instructions call for some amount of vertical deflection, and then getting the final setting by listening to the disk playing. A good vertical bearing/pivot should be free enough to let the force gauge read the correct value (within limits). When I get the cantus design set up and playing well, I have the feeling the VTF is too high. Any comments on this please?
BillG
Good post! I just want to make it clear that I'm only trying to get around the problem I'm having with trying to establish a given VTF. As far as playing warps and eccentricity in records goes, my Cantus with the glass V track gives no trouble. None of my records have more than small warps and next to no runout. So what am I complaining about? I would like to have the little Ortofon VTF balance able to show me what that force is. I have to carefully place the stylus on the balance and tap it and jiggle it and try to see that the position of the bearings in the V isn't biasing the VTF. To me it appears that the only true VTF is achieved under the dynamic condition of playing a record. Even if the inner ball race is positioned well within the radial free play range of that bearing, we still have the starting torque relative to the running torque of the bearing confusing the reading. Unfortunately the only observable indication of VTF is the amount of vertical deflection of the stylus cantilever with the record being played. IIRC Bo's setup instructions call for some amount of vertical deflection, and then getting the final setting by listening to the disk playing. A good vertical bearing/pivot should be free enough to let the force gauge read the correct value (within limits). When I get the cantus design set up and playing well, I have the feeling the VTF is too high. Any comments on this please?
BillG
Moray and BillG,
Your recent posts are good stuff. Eaglebear definitely resuscitated this thread.
Bill - I couldn't set VTF on my arms using a Shure balance so I bought a cheap HF digital. According to it I can get down to about 1 gram. I think the balance types just don't respond to short light LT arms. I'm looking forward to your take on the vertical bearing idea.
Like you, I'm busy with yard and house projects, so audio stuff has been set aside.
Your recent posts are good stuff. Eaglebear definitely resuscitated this thread.
Bill - I couldn't set VTF on my arms using a Shure balance so I bought a cheap HF digital. According to it I can get down to about 1 gram. I think the balance types just don't respond to short light LT arms. I'm looking forward to your take on the vertical bearing idea.
Like you, I'm busy with yard and house projects, so audio stuff has been set aside.
Bill and Doug: thanks for the reply's and as always your input is great to have. I would love to see this thread spawn some great diy designs after the Cantus. I think that Bill is correct in that setting the VTF is best done by ear and I have found that the cantilever angle sometimes just has to be ignored to achieve the best possible sound. I normally start off with the body of the cartridge square to the record surface. I alternate between adjusting VTA and down force. If I make a large adjustment in VTA I usually re balance the arm and set the down force to where i wanted it and then play with that up and down to see how things sound. Repeating this process two or three times usually walks the cartridge into a good sounding position. Best regards Moray James.
Doug - Moray - others,
Even the yard will wait for a few weeks. Last Monday I had a pacemaker implanted. Most unexpectedly. back home and recovering. All going well so far, feeling good. I'll be lurking, but not doing anything in the shop for short time.
BillG
Life goes on...
on VTF and VTA: I think Moray's approach for setting the VTA and VTF is reasonable. Remember that almost every analogue guy out there (as in reviewers) follow Moray's approach as well. One seemingly small adjustment can have a profound effect on the others. And use a little more of the horse sense that you folks have demonstrated thus far: even though not easily adjusted via the arm, consider adjusting azimuth as well. Something as easy as a card stock shim can be used on one side or the other to adjust that. The same can be done fore and aft to make gross VTF changes.
Last week (er..2 weeks ago) I visited Moray at his home and had quite a great experience with him and his brother (Robert). But I also realized that I am:
Going back a few posts and the discussion of using a knife edgedd or flanged bearing as per Bo's drawing provided by Moray. This can work, but in a glass tube a "track" needs to be cut into the glass without causing a break. This maybe nearly impossible to do. In a plastic tube, it should be relatively easy, but the arm will not be permitted leave the track and that can bring along with it other concerns.
BillG: In the BIG scheme of things all other endeavors pale by comparison. Please get as well as possible as quickly as possible.
on VTF and VTA: I think Moray's approach for setting the VTA and VTF is reasonable. Remember that almost every analogue guy out there (as in reviewers) follow Moray's approach as well. One seemingly small adjustment can have a profound effect on the others. And use a little more of the horse sense that you folks have demonstrated thus far: even though not easily adjusted via the arm, consider adjusting azimuth as well. Something as easy as a card stock shim can be used on one side or the other to adjust that. The same can be done fore and aft to make gross VTF changes.
Last week (er..2 weeks ago) I visited Moray at his home and had quite a great experience with him and his brother (Robert). But I also realized that I am:
- less tweaky than either of them
- I am married and they are not so whetherr I realise it or not WAF is a consideration that I must pay attention to
- serious improvements can be done that fly in the face of convention
- Moray is far more creative than most that I have met and should become an artist
(in the usual sense, he is already an artist in regards to audio matters...)
Going back a few posts and the discussion of using a knife edgedd or flanged bearing as per Bo's drawing provided by Moray. This can work, but in a glass tube a "track" needs to be cut into the glass without causing a break. This maybe nearly impossible to do. In a plastic tube, it should be relatively easy, but the arm will not be permitted leave the track and that can bring along with it other concerns.
If a track or groove is cut on the glass tube, wouldn't it render a glass tube not necessary. A simple aluminum L bracket or V grooved track (like in post#225) would be suffice, right?
BillG,
Yeah, what Stew said. Take it easy, be good to yourself, get healthy, then get back to us. I wound up with a stent about two years ago. The relief was huge and immediate. I hope that's true for you, too.
LT stuff: I tried knife edge and spherical wheels. I hit machining limits real fast and both designs require precision work. Beyond that, I think there are inherent problems to both approaches.
Moray - My adjustment process mirrors yours. The end step is an SRA and azimuth check, which may involve disregarding arm/cartridge body angles to some extent.
Stew - I was beginning to think Moray was as elusive as Sasquatch up there in the North. Nice to have a credible sighting.
At the risk of being cast out as a heretic, I've been thoroughly enjoying a restored Rek-O-Kut L-34 with a ROK S-120 pivot arm. I made the plinth roomy enough to accommodate an LT, but haven't made the switch yet. I think the combination of idler and LT might be a good one. Have you guys seen eaglebear's post about doing something similar?
Yeah, what Stew said. Take it easy, be good to yourself, get healthy, then get back to us. I wound up with a stent about two years ago. The relief was huge and immediate. I hope that's true for you, too.
LT stuff: I tried knife edge and spherical wheels. I hit machining limits real fast and both designs require precision work. Beyond that, I think there are inherent problems to both approaches.
Moray - My adjustment process mirrors yours. The end step is an SRA and azimuth check, which may involve disregarding arm/cartridge body angles to some extent.
Stew - I was beginning to think Moray was as elusive as Sasquatch up there in the North. Nice to have a credible sighting.
At the risk of being cast out as a heretic, I've been thoroughly enjoying a restored Rek-O-Kut L-34 with a ROK S-120 pivot arm. I made the plinth roomy enough to accommodate an LT, but haven't made the switch yet. I think the combination of idler and LT might be a good one. Have you guys seen eaglebear's post about doing something similar?
the elusive Moray James...
... in fact exists (I've known for at least 15 years on again and off again) and is one of the smartestguys I know (I think unless he is so good at the BS that it passes for "intellegence. Another is a good engine rebuilder, a equipment operator for the city, and a few others. 1 engineer (who is perhaps the most well rounded person of any of the "geek" types I've met) and that math guy from the island.
The idea of machining a track for the knife edged wheel to travel in is just to limit the fore and aft movement of the arm. Yes, a V-groove would accomplish the same thing and is much easier to implement.
As far as being a heretic, to some extent we all are. "What, you listen to LPs?" Some folks just never learn to trust their ears. Or feel they can't.
... in fact exists (I've known for at least 15 years on again and off again) and is one of the smartestguys I know (I think unless he is so good at the BS that it passes for "intellegence. Another is a good engine rebuilder, a equipment operator for the city, and a few others. 1 engineer (who is perhaps the most well rounded person of any of the "geek" types I've met) and that math guy from the island.
The idea of machining a track for the knife edged wheel to travel in is just to limit the fore and aft movement of the arm. Yes, a V-groove would accomplish the same thing and is much easier to implement.
As far as being a heretic, to some extent we all are. "What, you listen to LPs?" Some folks just never learn to trust their ears. Or feel they can't.
I was in a local record store recently - we actually have at least two in a county of about 280k - when a young mother and two kids - a 14-or-so daughter and a son maybe eight, both apparently very nice kids. I was in the vinyl section and surprised to see them. The son asked the clerk for a particular album and answered "vinyl" when asked which media he wanted. I gave the kid a big atta boy and asked the mother about that choice. She said both kids - the daughter was already deep in the vinyl collection - decided on their own and the daughter already has a TT. I got bemused looks for my happy dance.
The knife edge wheels I built rode in an aluminum V trough. In most ways they worked well, but they had a tendency to hang up. I checked both the wheels and the trough with magnifying glass and saw surprising roughness in the trough and facets on the sides of the wheels right at the circumference. The inherent problems I mentioned are the extra radius exaggerating bearing wobble and magnifying the response to bumps.
A lot of the brightest people I've "met" post in DIY forums.
The knife edge wheels I built rode in an aluminum V trough. In most ways they worked well, but they had a tendency to hang up. I checked both the wheels and the trough with magnifying glass and saw surprising roughness in the trough and facets on the sides of the wheels right at the circumference. The inherent problems I mentioned are the extra radius exaggerating bearing wobble and magnifying the response to bumps.
A lot of the brightest people I've "met" post in DIY forums.
Bill: wow take your time and relax. I had a 1.25 inch long stent put in after a heart attack in late December and seven months out I am still on the mend. Maybe I should start looking into designing and building a new and improved Jarvex heart. Maybe it's the age but this seems to be a big club. Feels good to be a member. gottta crash will read more posts tomorrow. Best regards Moray James.
Moray,
WOW! Whodathunkit! Thanks guys for all your encouragement and sharing your experiences on this OT stuff. The closeness of this "club" hit me yesterday pardon the pun (club - hit). Those people talking about tech things are real folks with feelings of compassion and care for each other. It is great to be a member.
Bill
Not quite sure how I feel about a compliment winch includes a description as a possible bullshitter but since it came from Stew then I know that his heart is always in the right place. This is a membership of great people who care about and love what they do and that goes for the people they encounter also.
Back to arm at hand (of which I have a couple), I think that a track for a rolling knife edge is likely to be more problematic than no track from a constructional point of view. With a tube to roll in the carriage will track as well (straight) as it has been designed to and if it gets off course a little the cartridge will simply drag it back into line. The rolling knife edge can easily slide on the surface of the tube. A trackless system also permits the arm assembly to deal with warps on the disk which a track would prevent. Just my 2 cents worth along with the bad arm/hand pun. Best regards Moray James.
so full of it...
Moray,
I was just trying to state that smart guys need not have degrees, and that a degree is not necessarily an indication of intelligence.I was implying that unless I am completely wrong about you and you are the "king of BS" then I've been taken in. And I know that isn't the case.
...and yes, perhaps the comment about cutting a track in a tube wasn't the best idea I've ever suggested...
PS: Moray did you get my email of this morning?
Moray,
I was just trying to state that smart guys need not have degrees, and that a degree is not necessarily an indication of intelligence.I was implying that unless I am completely wrong about you and you are the "king of BS" then I've been taken in
. And I know that isn't the case....and yes, perhaps the comment about cutting a track in a tube wasn't the best idea I've ever suggested...
PS: Moray did you get my email of this morning?
Moray,
I was implying that unless I am completely wrong about you and you are the "king of BS" then I've been taken in
Easy Nook - both Moray, ZM, Terry O., (and many others) know of my ability to BS with the very best. I do not claim to be the King of BS because we don't have a royal bloodline here in the States - and I refuse to run for election to the office because I am far outclassed by the professional politicians and their public relations staff.
BTW - 2008 - 5 way bypass.....
Stiffer tone arm....
Doug: I can't offer any assistance with math related problems without making more problems.
I do have a suggestion for making a stiffer tone arm for the Cantus. Bo told me numerous time that small diametre stiff tubes worked best better than large diametre tubes such as arrow shafts or even carbon composite tubes. So if you take two tubes like the ones Bo uses in the Cantus and you place them side by side you can Krazy glue them together. Same overall mass but a much stiffer and better damped assembly. Damping the inside of the tubes also helps. The top secret damping material for custom made competition arrow shafts is coffee creamer powder You might want to give it a try. Best regards Moray James.
Doug: I can't offer any assistance with math related problems without making more problems.
I do have a suggestion for making a stiffer tone arm for the Cantus. Bo told me numerous time that small diametre stiff tubes worked best better than large diametre tubes such as arrow shafts or even carbon composite tubes. So if you take two tubes like the ones Bo uses in the Cantus and you place them side by side you can Krazy glue them together. Same overall mass but a much stiffer and better damped assembly. Damping the inside of the tubes also helps. The top secret damping material for custom made competition arrow shafts is coffee creamer powder You might want to give it a try. Best regards Moray James.
Moray,
Math is terra incognita complete with "here be monsters" for me, but if someone puts a good program together, I'm not too proud to use it and I like what I think I see so far. I really want to be able to generate some numbers and do measurements. I think it would be fascinating and valuable to get a picture of what LTs do, how they respond to signal and disturbance induced resonances as well as their inherent material and construction resonances. I've done a couple of years of intuitive tinkering - I'd like to see if I can get a bit more rigorous.
Thanks for the hint about ganging tubes - that sounds promising. I'd heard about coffee creamer somewhere and I've got some wood flour that might serve, too.
Math is terra incognita complete with "here be monsters" for me, but if someone puts a good program together, I'm not too proud to use it and I like what I think I see so far. I really want to be able to generate some numbers and do measurements. I think it would be fascinating and valuable to get a picture of what LTs do, how they respond to signal and disturbance induced resonances as well as their inherent material and construction resonances. I've done a couple of years of intuitive tinkering - I'd like to see if I can get a bit more rigorous.
Thanks for the hint about ganging tubes - that sounds promising. I'd heard about coffee creamer somewhere and I've got some wood flour that might serve, too.
Hi Guys,
Pulse 60, strong and regular, surgery healing and beginning to feel like myself.
Moray, I've been wanting to try the small diameter tubing since I began this project. Now you have reawakened that idea. Years ago there was a commercial, pivoted arm that used three such tubes in an open, triangle, parallel tube design like a Birdcage Maserati chassis. I mentioned that idea somewhere in this forum. So I been looking for a tube source. Easy to find if you want to buy by the ton or mile etc. Three small pieces, no go. What might work just fine is the metal tube from Cross style ball point pen refills. Soon as I get out I'll check the stationery stores and see if I can get some for a reasonable price. Regarding the math and Doug's wish to get a bit more rigorous, I share that desire, but I too am not a math genius. I have been wondering for a while just how empirical BO's product actually is. Any idea?
Nice to be back,
BillG
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BillG,
That's great news. Welcome back.
I like the idea of metal ball point pen tubes, especially a trio. Might work very well and could look good, too. A guy at a local kite shop gave me a piece of carbon fiber kite spar about 4.8mm OD x 2.5mm ID. Should work well for Moray's twin tube suggestion. I got to see a "Bird Cage" in action at Riverside in about 1960. The power to weigh ratio made it fast as hell, but just a tad squirrelly.
Did you get a chance to check out the program Jan Didden (janneman) linked to? There are more than a few eff mass and res calculators, but this is the first one I've seen that looks like it might be applicable to LTs.
That's great news. Welcome back.
I like the idea of metal ball point pen tubes, especially a trio. Might work very well and could look good, too. A guy at a local kite shop gave me a piece of carbon fiber kite spar about 4.8mm OD x 2.5mm ID. Should work well for Moray's twin tube suggestion. I got to see a "Bird Cage" in action at Riverside in about 1960. The power to weigh ratio made it fast as hell, but just a tad squirrelly.
Did you get a chance to check out the program Jan Didden (janneman) linked to? There are more than a few eff mass and res calculators, but this is the first one I've seen that looks like it might be applicable to LTs.
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