Gents, if you don't mind I just want to remind you that the effective mass of a tonearm is not the weight you can read off when you put it on a pair of scales. Unfortunately it's not that easy.
Greetings, Hansrudolf
Greetings, Hansrudolf
Greetings to you Hansrudolf,
If you were referring to my arm weights in answer to Squiffy"s question. Thats what they were simple weights of objects, Not effective mass or anything else.
Some seriously dodgy music tastes on this site
"Psycho Killer" Talking Heads.
Jay
If you were referring to my arm weights in answer to Squiffy"s question. Thats what they were simple weights of objects, Not effective mass or anything else.
Some seriously dodgy music tastes on this site
"Psycho Killer" Talking Heads.
Jay
My arm is up n running!
Size has grown to 280 mm or about 11", fits on the table quite nice.
I'm stunned by the very smooth bearing, for sure less friction than the original arm on this table. Probably it's a little heavy, had to use an 160 grammes weight to balance it.
Cannot really judge the qualities of the arm yet. Have to fiddle around with it a little more, alignment, tracking weight and VTA are still a first try. First impressions are not over the moon. Nothing bad, but no giant leap forward either. But maybe, with some more time. At the very least, handling the wobbly arm with no tonearmlift is easy peasy.
Already thinking about the next version of this arm. Less weight in the headshell area, teflon bearing cup, maybe 12". And a better way to take some pictures 🙂
Questions, what would be the optimal place for the cabling to leave the armwand in the center? What do you do with earthing the arm?
An externally hosted image should be here but it was not working when we last tested it.
Size has grown to 280 mm or about 11", fits on the table quite nice.
I'm stunned by the very smooth bearing, for sure less friction than the original arm on this table. Probably it's a little heavy, had to use an 160 grammes weight to balance it.
Cannot really judge the qualities of the arm yet. Have to fiddle around with it a little more, alignment, tracking weight and VTA are still a first try. First impressions are not over the moon. Nothing bad, but no giant leap forward either. But maybe, with some more time. At the very least, handling the wobbly arm with no tonearmlift is easy peasy.
Already thinking about the next version of this arm. Less weight in the headshell area, teflon bearing cup, maybe 12". And a better way to take some pictures 🙂
Questions, what would be the optimal place for the cabling to leave the armwand in the center? What do you do with earthing the arm?
Nice tonearm.
Very nice looking arm, it appears to be very well constructed.
What materials did you use? Using a 160 gram counter-weight is no big deal other than adding the mass. It will just end up being closer to the pivot than say a 80gram or 60 gram one. Check the mass of the arm, with everything except the counter-weight. Then do the resonance /cartridge matching equation to make sure that the weight is a good match with your cartridge compliance. I had one of the cats knock mine off the turntable. The cantilever to the cartridge survived, and I wasn't worried about the arm. These arms are pretty tough.
I usually drill a small hole about 1/2" in front of the bearing. Just slide the wiring through and you are done. I usually also add a separate wire and solder it to a spot near the headshell end of the arm wand for a ground. Even grounded the arm can buzz pretty good, but I do not use any shielded cabling whatsoever. To fix any buzz I just ensure that the connections to my preamp are good, and move the wiring around until there is no buzz.
Very nice looking arm, it appears to be very well constructed.
What materials did you use? Using a 160 gram counter-weight is no big deal other than adding the mass. It will just end up being closer to the pivot than say a 80gram or 60 gram one. Check the mass of the arm, with everything except the counter-weight. Then do the resonance /cartridge matching equation to make sure that the weight is a good match with your cartridge compliance. I had one of the cats knock mine off the turntable. The cantilever to the cartridge survived, and I wasn't worried about the arm. These arms are pretty tough.
I can take pictures, but for whatever reason I can't post them. 12" is my "standard arm" length.
I usually drill a small hole about 1/2" in front of the bearing. Just slide the wiring through and you are done. I usually also add a separate wire and solder it to a spot near the headshell end of the arm wand for a ground. Even grounded the arm can buzz pretty good, but I do not use any shielded cabling whatsoever. To fix any buzz I just ensure that the connections to my preamp are good, and move the wiring around until there is no buzz.
Overweight is mainly around the headshell. Armtube is an carbon/alu arrowshaft, and was only about 3 gram, total weight about 15 gram. Used brass for the headshell, next arm I will be using less metal, and more alu.
I fixed the mass wire to the armbase, thinking that the arm would work as conductive shielding. Will run a wire to the headshell next try, see if it makes a difference.
I fixed the mass wire to the armbase, thinking that the arm would work as conductive shielding. Will run a wire to the headshell next try, see if it makes a difference.
Just try this one as a start with light rods and headshells with a suiting cart of yer choice (high compliance) 🙂
Very good 🙂
Very good 🙂
Is it because the pics are too big? If you use Windows, use Paint program in Start> Accessories to shrink jpg. Just use resize tool. Start with 50% of original size.
One very good combination with the 219 is an old Sonus Blue Gold 🙂
Just love it!
I will when time permits try a AKG Supernova as well - high hopes...
Regards
Just love it!
I will when time permits try a AKG Supernova as well - high hopes...
Regards
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The P8ES SuperNova didn't like the arm. Lot of resonances so it likes a heavier arm. The Sonus Blue Gold is perfect to the arm.
Regards
weight and the 219...
I think you'll find that adding a little mass is pretty easy. There's lots that can be done in terms of external damping materials as well internally. One quick and easy method is as per Sumiko's (old) analog survival kit. It can be easily seen from the picture you posted of the "proof of concept" that the headshell can easily be removed, so heat shrink can work well. Even just some O-rings will work as long as they are spaced at uneven intervals.
If wanting something else, even polyurethane spray foam could work nicely. It's just that if you aren't happy, a little difficult to reverse.
I think you'll find that adding a little mass is pretty easy. There's lots that can be done in terms of external damping materials as well internally. One quick and easy method is as per Sumiko's (old) analog survival kit. It can be easily seen from the picture you posted of the "proof of concept" that the headshell can easily be removed, so heat shrink can work well. Even just some O-rings will work as long as they are spaced at uneven intervals.
If wanting something else, even polyurethane spray foam could work nicely. It's just that if you aren't happy, a little difficult to reverse.
rb250?
hey stew, respect.
I have an rb250 that doesn't owe me anything (got it free); how about I cut its arm off, tap a thread and die the arrow to match and use the bearing end of the 250? I would need to make a pu2 style headshell or one like yours, but it could be almost any length. I have never had a unipivot and like your approach, so am determined to have a go, but the 250 does have good bearings, which may make for an easy build. im a newbie to forums but have played with records for a few years and love music. those oracles are a work of art but a bit pricey over here (uk), so I will be using a lenco.
best regards, paul
hey stew, respect.
I have an rb250 that doesn't owe me anything (got it free); how about I cut its arm off, tap a thread and die the arrow to match and use the bearing end of the 250? I would need to make a pu2 style headshell or one like yours, but it could be almost any length. I have never had a unipivot and like your approach, so am determined to have a go, but the 250 does have good bearings, which may make for an easy build. im a newbie to forums but have played with records for a few years and love music. those oracles are a work of art but a bit pricey over here (uk), so I will be using a lenco.
best regards, paul
Hi Paul
In effect that's what the Funk Firm have done with one of their arms-others have also-including me. Trouble is the bearings on the 250 are not that great. If I were you, I's go down the unipivot route. A lot less work and the results are certainly superior by quite a margin
Chris
In effect that's what the Funk Firm have done with one of their arms-others have also-including me. Trouble is the bearings on the 250 are not that great. If I were you, I's go down the unipivot route. A lot less work and the results are certainly superior by quite a margin
Chris
hey chris, I thought the bearings were the only good thing about the 250. I have braced the vertical bearings as the adjusters are set into a paste and I had to take them apart to rewire the arm (that's why the dealer gave it away). if the funk think its a good design I may be getting a real bargain for a little effort (are they the old pink triangle?). the horizontal bearings are on the tight side, and ive washed them through with spirit and then oil because they just wont adjust. no more skipping, but I still don't apply the anti-skate. I once thought of compressing the arm tube with a bicycle spoke because it rings like a bell, but not got round to it yet.
wta
hey chris, I just looked you up on lencoheaven, I see you have made an arm like the wta, respect. I remember a review many years ago, comparing the wta with all sorts of unconventional designs, including one that used a mercury bath contact for the arm wires - you couldn't get away with that these days. have you tried dilatant fluids - you know, like cornflower paste, that are hard when stressed but fluid when relaxed? probably no good, but just a thought - blue sky.
hey chris, I just looked you up on lencoheaven, I see you have made an arm like the wta, respect. I remember a review many years ago, comparing the wta with all sorts of unconventional designs, including one that used a mercury bath contact for the arm wires - you couldn't get away with that these days. have you tried dilatant fluids - you know, like cornflower paste, that are hard when stressed but fluid when relaxed? probably no good, but just a thought - blue sky.
Hi
I'm sure that Funk (who used to be PT) change the bearings for higher spec ones, as do quite a few of those who up-spec the basic 250. Even though, shouldn't get any skipping from them. I've had lots through my hands and never had tracking problems-they just don't sound that great-that's all......
Chris
I'm sure that Funk (who used to be PT) change the bearings for higher spec ones, as do quite a few of those who up-spec the basic 250. Even though, shouldn't get any skipping from them. I've had lots through my hands and never had tracking problems-they just don't sound that great-that's all......
Chris
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