Two years ago i purchessed a broken DD Dual turntable for its tonearm which was in good condition. I also have a B&O MMC20E cart that was never used from a broken B&O turntable , some Easton archery Jazz arrows made out of 7075 aerospace alloy and a a broken Garrard whose counterweight needed to be used too...Now i need to wire it , put the phono pre inside the wooden box and listen to the damn thing.
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Same issues as an engine connecting rod. A super long rod/arm really reduces the geometry errors but increases the moving mass. While you can counter-balance gravity forces, bass resonance and record warp finds a lot of mass to push.
Certainly will make your friends jealous.
Certainly will make your friends jealous.
I'm using Garrard sp25 counterweight so i get approximately its moving mass while it had a short and very heavy tonearm.I'll be using it with a better turntables though)dual 701 and dual 1219).I can still cut it to 12 inch if it's too long...will see about it next days.I'm still envious on the original B&O turntable whose tonearm i broke due to transport ...I found that B&O the most genious turntable i ever saw anywhere...I still tink they were better than any other company at building turntables.
I made the first trials on vinyl and realized all the angles were wrong yet still it sounded acceptably well, but after giving an online calculator a chance and comparing the results between 14.8 inch and 12 inch i realized what a waste of opportunities would be to not reduce te length to a more standard 12 inch value.By the way Kuzma got more awards on 9 inch tonearms than on any other tonearms they sell which simply makes Logfren and ther rest of theory masters real GODS of this field and ignoring teir math is simply stupid .The reason i don't go back to 9 inch though is because i need to keep my tonearm totally independent and able to use with external turntables.I already have all the power supply and phono preamp inside the wooden box , added all the necessary shielding and damping and in a few days i'll have a 12 inch tonearm instead of a useless 15 inch one...I also tried something weird for a B&O mmc20en, i used a powerful magnet at the back of the cartridge to fix the cart to the tonearm along with some polyurethane damping with the idea that i might increase the magnetic field of the cartridge itself ...I have no idea how good that can be, but i can remove the magnets easily if unsatisfied.I think that if B&O would have had today's magnets their cartridges would have been even better...
After a few trials on a shorted 14.8 inch effective length, a deep dive into te tonearm theoretical side and after seeing the theory confirmed by te fact that Kuzma's 9 inch tonearms got more awards in Japan than all their other longer and much more expensive versions I took a clearcut decision of going down to 12 inch as it still allows me to use the tonearm independently with any turntable. I managed to cut the toneram to get a total effective length just below 12 inch (0.01 degrees in tracking angle error) and identical results according to vinylengine calculator. Cutting, filing and measuring those angles was an ordeal honestly...
Next days I will rewire the tonearm.I actually chose some " anti-audiophile" 0.08mm diameter enamelled copper wires with a very thick enamell on them.
The signal wires were twisted and had about 60pf on the 14.8 inch version, probably 50pf will be their final value.
Hust for the fun of it, if I'd have the money I think I could bet a million dollar on my15 dollars /kg copper wires I have from before 1989, made right in the communist era of my country, against the most expensive litz wire on the planet for the sound of it as long as the cartridge internal wiring is actually much thinner and no two wires in parallel. Besides even with all the wrong angles of my first tonearm iteration I still got the kind of highs I got with shure v15type 3 on dual 701, 9 inch tonearm with my zen wiring .Inside the tonearm wooden box base i have an r-core transformer and my Taylor phono preamp. Even if i don't add the 2.5mm attaching magnet which is a sensitive choice to cartridge magnetism itself i can still get away with the already cut 18 degrees offset angle
Next days I will rewire the tonearm.I actually chose some " anti-audiophile" 0.08mm diameter enamelled copper wires with a very thick enamell on them.
The signal wires were twisted and had about 60pf on the 14.8 inch version, probably 50pf will be their final value.
Hust for the fun of it, if I'd have the money I think I could bet a million dollar on my15 dollars /kg copper wires I have from before 1989, made right in the communist era of my country, against the most expensive litz wire on the planet for the sound of it as long as the cartridge internal wiring is actually much thinner and no two wires in parallel. Besides even with all the wrong angles of my first tonearm iteration I still got the kind of highs I got with shure v15type 3 on dual 701, 9 inch tonearm with my zen wiring .Inside the tonearm wooden box base i have an r-core transformer and my Taylor phono preamp. Even if i don't add the 2.5mm attaching magnet which is a sensitive choice to cartridge magnetism itself i can still get away with the already cut 18 degrees offset angle
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Hi,
Separated TA pod is I think is a good solution.
Regarding the length of the TA I like 12 Inch, but a 10 Inch good TA is probably more dynamic and faster than a 12 Inch TA.
Adelmo
Separated TA pod is I think is a good solution.
Regarding the length of the TA I like 12 Inch, but a 10 Inch good TA is probably more dynamic and faster than a 12 Inch TA.
Adelmo
I think not.
It is impossible to be sure that there is no relative movement between the arm and the disk.
It is impossible to be sure that there is no relative movement between the arm and the disk.
@russel
After reading Tejinder article I realized you can't get better than the original Beogram 2202 toneram when using its cartridge , but i wanted to use this tonearm externaly with some Duals and PE turntables so i had to have at least 12 inch for that matter.I have an etremey light tonearm attached directly to the cartridge though and if the results won't be good enough, cutting a toneram from 12 to whatever length might accomodate a better performance is much easier than making it longer 🙂 On the other hand i'm using a very high quality elastic and esily replaceable adhesive between cartridge and tonearm and i hope that will solve a lot of the possible problems except the vertical behavior of the tonearm effective mass .Still didn't have a try, but it took me 3 weeks only to make the pure horror lift system work....
After reading Tejinder article I realized you can't get better than the original Beogram 2202 toneram when using its cartridge , but i wanted to use this tonearm externaly with some Duals and PE turntables so i had to have at least 12 inch for that matter.I have an etremey light tonearm attached directly to the cartridge though and if the results won't be good enough, cutting a toneram from 12 to whatever length might accomodate a better performance is much easier than making it longer 🙂 On the other hand i'm using a very high quality elastic and esily replaceable adhesive between cartridge and tonearm and i hope that will solve a lot of the possible problems except the vertical behavior of the tonearm effective mass .Still didn't have a try, but it took me 3 weeks only to make the pure horror lift system work....
It's a 0.3mm elastic jelly like but firmer adhesive which will damp any low resonance decoupling the cart from the arm.Altough the usual way is to use some brass to damp the cartridge trough weight , that's a commercial approach aimed at giving long time reliable use, although sacrificing effective weight performance, while this is my tonearm and i can replace that damping any time in the future . Schuller Eh'klar - DUO TAPE double-sided adhesive tapes
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Now, while the jelly do damp lower resonance it doesn't damp higher ones...and the long hollow straight line tube made of aerospace alloy proved to be a real amplifier for any high pitch vibration picked up by the whole tonearm setup.Touching the tonearm wires makes it a good violin, which is annoying as using some polyurethane material on the tonearm didn't made the resonances much lower...Now i get that tonearms need to be either connical shape or as short as possible and HEAVY.High grade carbon conical shape are very low quality shields if any so i can clearly tell that vinyl wear is a must and there's basically nothing you can do about it if considering pivot type tonearms.Most probably, i'll never consider building a long pivot tonearm again if any pivor tonearm at all...it's not that i can hear those vibrations when in the turntable system which is really well damped , but i am only after pure performance if it can be obtained.Thus my next project will surely be tangential tracking as wearing vinyls is something we can all do for very cheap or too expensive...and i have feeling that Tesla nc430 or NAD5230 plastic tonerams are pretty much the best you can get technically, so why going with thousand dollars ultra heavy tonerams reading 300 dollars collection wearable vinyls?Then there are already so many guys providing digital copies of some of the best analogue reproductions outhere...
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HI,
You may try Bamboo arm tube and if you need more mass insert inside glued balsa as I did. It do not have the claimed resonance of the aluminium, to me sounded not too bad. My bamboo was well aged anyhow, no surface treatment.
For the rear weight and cart head shell I used soft aluminium.
Rgds
Adelmo
You may try Bamboo arm tube and if you need more mass insert inside glued balsa as I did. It do not have the claimed resonance of the aluminium, to me sounded not too bad. My bamboo was well aged anyhow, no surface treatment.
For the rear weight and cart head shell I used soft aluminium.
Rgds
Adelmo
I suppose you rely on wire's shielding then...does it work with any cartridge?Half of the wiring is not shielded anyway, but i get significant hum from those exposed wires as i don't have balanced inputs with mm carts.Truth is that i used bare ennameled copper wires which are mecanically and capacitively in close contact with the aluminium tube.For a similar behavior in someone else's tonearm it was suggested to fill the whole tonearm with polyurethanic foam and trap the wires inside but that is irreversible...
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HI,
The wire I used for the first test in the TA as in the picture were taken from a broken mouse from my PC.
I used Denon DL 103 mc cart and I have no hum at all. Also I do not have balanced interconnect in the line of the system.
To connect my pre phono to the integrated amp the interconnect wire are not shielded as well and no hum.
I grounded the TA aluminium base together with the TT metal to the pre phono.
Rgds
Adelmo
The wire I used for the first test in the TA as in the picture were taken from a broken mouse from my PC.
I used Denon DL 103 mc cart and I have no hum at all. Also I do not have balanced interconnect in the line of the system.
To connect my pre phono to the integrated amp the interconnect wire are not shielded as well and no hum.
I grounded the TA aluminium base together with the TT metal to the pre phono.
Rgds
Adelmo
I only used exposed twisted 0.08mm ennameled copper wires...not sure entirely if the wires are the main culprit for that irreducible hum as the phono preamp is unshielded and the hum gets noticeable higher only if i touch the wires with my hand ...mmc20en cart is a very sensitive anyway, it has a separate wire connecting the shield case to ground.along with the the tonearm .I'll try different shielded wires.I thought i could go minimal, but it seems that i need some cushion between the tonearm and the wires anyway cause some of high freq noise is induced as in a guitar string directly from wires to tonearm pipe through capacitive coupling, while most of it can simply be nulled by detaching the cart from the tonearm so mechanical coupling is the main factor and making a heavy brass coupling as in most commercial tonearms will deffinitely make the system heavier and i wanted to have it as light as possible but physics doesn't allow me that.Even two layers of 0.5mm jelly double sided glue tape didn't help enough and having too thich jelly tape will make the cart wobble too much .Bamboo or carbon fiber is always a cheap option for tonearm although double conical decoupled walls tonearms should be considered with carbon, i already built something like that years ago, but i'm trying to get some benneffit from aluminium shielding if possible and 12 inch is really tough job for straight tubes and J or S shaped tonearms aren't something i can build .I still have some ideas how to solve this mechanical piezo like resonance puzzle so i'll try more of them next week, but first i need to have the wires cushioned .