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JazzBones
09-11-2010, 14:46
Advice required please: The question is, 'where is the best place on a 12** to connect the tone arm earth lead (not the end that goes to the pre/control amp)'? The Tekko arm seems to connect to a removable retaining screw on the pitch control, would it be best to continue with this arrangement or is there a better pozzy on the 12** METAL bodywork? Could one of the three retaining screws used for the metal arm plate be used for safer earthing?

Tips and the benefit of your experience will be appreciated as well as a pic or two if poss?

Thanks

Jazz, aka Ron:confused:

Gdg
09-11-2010, 15:01
Ron, just for the sake of curiosity, why do you want to change original connecting point?

Anyway, I could guess that using a whatever screw on the alu chassis is sub-optimal, since there could be some paint inside the holes not assuring a correct electrical conduction.

DSJR
09-11-2010, 16:05
Ron, can you remember how we wired Grace arms to the LP12?

You may have to break into the tonearm earth wire around an inch from the tonearm plug and solder a little "tail" to it, connecting the far end of the tail to the turntable earth tag. I did summat like this on my TD125 with Audio Origami exit cable -

http://i132.photobucket.com/albums/q8/DSJR_photos/DSCF1418.jpg

You can't see the "T" join sadly, but one blue wire connects the sprung top plate to the under-chassis and the other from top plate tag goes to the main arm earth wire.

colinB
09-11-2010, 16:47
When i took out the standard tone arm and replaced it with a jelco.
I had to do exactly that and put the earth strap on the pitch control.
Did the job, no earth hum.

JazzBones
09-11-2010, 16:54
Ron, just for the sake of curiosity, why do you want to change original connecting point?

Anyway, I could guess that using a whatever screw on the alu chassis is sub-optimal, since there could be some paint inside the holes not assuring a correct electrical conduction.

Hello Giovanni, good to see you over this side and to chat again! I was wondering if the was a better place elsewhere to anchor the earth wire other than on the pitch control earth wire as I will will be using a different armplate, Linn geometry and I was curious to see what everybody else did? I learnt from DSJR many years ago to always scrape the paint away to make a clean metal to metal connection. On the later date Linn Sondeks there is now provision for tapped screws at the designated earthing points making life easy. Linns beyond 20 years old needed the arm earth tag to be soldered to the metal subchassi which was a right pain in the butt and it wasn't always a clean finish if you only had a certain amount of time to fully assemble and fettle a Linn.... nowadays its easy peesy :mex:

What are you doing with your MN bearing, I'm keeping mine:)?

Jazz, aka Ron

JazzBones
09-11-2010, 17:02
When i took out the standard tone arm and replaced it with a jelco.
I had to do exactly that and put the earth strap on the pitch control.
Did the job, no earth hum.

Right, thats what I'm going to do... if its good enough for Technics who am I to question the application and you have kindly advised that there is no probs, thanks. I was concerned about hum but I do feel that a sensible clean metal to metal connection is okay as well.... just interested how people go about a certain job to achieve the same end result ;)

Thanks mate

Jazz, aka Ron

JazzBones
09-11-2010, 17:13
Thanks DaveO, can always count on you to come up with the goods and thanks for the pics, maybe someone will teach me how to post pics etc. Promise, no girlie centre fold stuff:eyebrows:

What do you think of the Audio Origami leads? Its very difficult to get a tone arm lead these days terminated at one end with BNCs (for Naim :rolleyes:), will probably have to get an SME to BNCs from Naim but it will more than likely cost an arm, leg and another body part of their choice, for one...any ideas on this one?


Ron:violin:

colinB
09-11-2010, 17:18
To be honest Ron , i was stumped as to where to put the earth wire. Not only had i taken away the standadvtone arm base plate, my new tone arm cable had two earth wires:scratch:
Gave it my best guess and it seems fine.

JazzBones
09-11-2010, 17:42
To be honest Ron , i was stumped as to where to put the earth wire. Not only had i taken away the standadvtone arm base plate, my new tone arm cable had two earth wires:scratch:
Gave it my best guess and it seems fine.

I thought that it was an awkward place to connect an earth wire (@ pitch control screw) and you know what its like having various ideas on the prob. I have toyed with having a floating lead, about a couple of inches long, secured at the pitch control end to which I can easily attach the arm earth wire by means of a locking bolt, nut and eye set up..sounds complicated, but its just an idea though and I don't think it will make life any easier?

Ron

Gdg
09-11-2010, 17:50
Hi Ron, still here, don't worry ;-)
Dave (DSJR) is right.
But I think the factory solution has no problem, except that you have to pay attention (I had to) when you re-assemble the TT, not to squeeze the wire with the internal heavy-mass counter-plinth.
Here are a couple of pics I got when I rewired my MK5, as an example, and I changed the stock wire with a thicker red/black one:
http://www.boxedspace.com/public3/SL1200_tonearm_base_earth.jpg

http://www.boxedspace.com/public3/SL1200_chassis_earth.jpg

colinB
09-11-2010, 19:26
Errr yes, squashed earth lead between the chassis. Be careful of that:o

DSJR
09-11-2010, 21:17
Thanks DaveO, can always count on you to come up with the goods and thanks for the pics, maybe someone will teach me how to post pics etc. Promise, no girlie centre fold stuff:eyebrows:

What do you think of the Audio Origami leads? Its very difficult to get a tone arm lead these days terminated at one end with BNCs (for Naim :rolleyes:), will probably have to get an SME to BNCs from Naim but it will more than likely cost an arm, leg and another body part of their choice, for one...any ideas on this one?


Ron:violin:

The Audio Origami leads are basically Van Damme Pro-Patch mic cable with standard Neutrik phonos and what looks like a custom tone-arm plug. I made mine up myself originally, but the 90 degree cardas based plug didn't take two cables, so I did away with the metal part. the wires are too easily strained and I had to convert it into a "straight" connection with glue-type heat-shrink to reinforce it - useless for the Thorens. I bought the AO lead for around half price on fleabay and it suits me fine.

Van Damme do a nice coax "Tour-Grade XKE" flexible cable with a silver strand or two in with the copper (works too ;)) -

http://cgi.ebay.co.uk/Van-damme-Instrument-Cable-XKE-Black-per-metre-/350312919271?pt=UK_Consumer_Professional_RL&hash=item519046f0e7

This should be ok with BNC's I think (without trying it).

I'm going to do a "DSR" here and suggest the BNC sockets on the Naim could go, to be replaced by decent isolated chassis phono sockets (my new old Croft uses some from Maplin) and maybe you could get some fancy phono plugs to match, WBT's or whatever, althoigh I'm still hugely fond of Neutrik-Pro ones. Although BNC's are fantastic at RF frequencies, which Naim cannot reproduce anyway due to their filtering, phono's are just as good at audio and ultra-sonic frequencies I think and their far easier to work with IMO..

JazzBones
09-11-2010, 22:34
Thanks for that one Dave. I did think of changing from BNC to RCA phonos a long time ago but Naim frightened me out of so doing:spank: but I will say stuff 'em and go ahead with the conversion.

As an aside, seeing Croft was mentioned, I was toying with the idea of using a croft pre-amp with my 135s if thats (?) possible as I have always hankered with the 1979/80s idea of a valve pre and tranny power along the lines of ARC pre and Krell 50s / 100s but nobody is able/willing to give me advice as to feasiability? Noel Keyward in the current letters page of HFW said he had good results with a Croft and Naim but got the Ice eye from Naim when he mentioned it to them... can't say I'm surprised! How would connections be made twix croft and 135s(CBs), any ideas or is it a forget and no no stick with the Naim pre???

Ron

PS to everybody else, sorry I've swerved of course on this thread:(

Marco
09-11-2010, 22:43
Hi Ron,

I did precisely that with my Croft preamp, when I originally bought it, before my 52/Supercap and 135s were sold, and the results were excellent, in many ways preferable to the 52/Supercap! Mine were 'olive' series 135s, though, not 'chrome bumper'.

What you need is a pair of phono to XLR cables, with long 'tails', so that the XLR ends can reach the inputs on both 135s. Flashback Sales will sort that out for you :)

Marco.

JazzBones
09-11-2010, 22:55
Thanks Marco, you can't see me but I'm on bended knee to you in gratitude.
You're the first ever POSITIVE response I've had to this long standing question of mine. All others have been a fat Neg, thanks mate, as soon as I am able to lay hands on a Croft I shall try it:)

Yours is a :cool: is it?

Ron

The Grand Wazoo
17-11-2010, 18:20
Give it a go - ARC/Levinson have worked for me for years

DSJR
17-11-2010, 21:05
The only problem you may have is with some exotic preamps with a bandwidth out to infinity and beyond....... My AVI pre goes out to 300KHz or higher and it drives my Quad II's OK, which would have the same potential difficulties as yours if the preamp bandwidth was too high.

Marco's tried it and it works. I'd suggest the Micro 25 "R" if you can afford it, together with the Flashback recommendation. I'm sure Mark Grant could assist with a superb interconnect too, but haven't tried conventional XLR plugs to see of they'll work with the Naim sockets (I'm sure the same plastic XLR plugs are available outside the "fraternity.")