My new not-really-a-Rega arm

[zharca]

I finally managed to get this arm finished. It had been sitting around for weeks waiting for the wire to come. Er, the wire I hadn’t ordered. :oops:


Rigged it up yesterday evening and straight off it’s sounding pretty good. Very clean and open. I played an old favourite and found a couple of string fingering noises I hadn’t heard before so I reckon it scores on the detail front, too.

Here’s some crummy pictures of it playing, just to show it really works.

www.audiomods.co.uk/images/newinstall1s.jpg
www.audiomods.co.uk/images/newinstall2s.jpg

Here’s a better one before wiring

www.audiomods.co.uk/images/IMG_1505-350.jpg

Now the bummer is that it sounds a damn sight better than the one I took off, but this was meant to be a “demo’ one, so what am I gonna do?

- keep it
- make a nice little box and lend it out for opinions on different decks/cartridges (which is what I’d originally intended)
- sell it. I have a guy who wants one without the vta thingy.

[j7]

hi jeff



that is totally stunning m8...job well done



this gives you the right to be known as the rb250 gold bling king...i just love how the arm looks like it can take on a graham phantom#

ps i think you should sell it...and buy another...maybe buy a few..coss there getting scarce

i found some new rb250 for agood priceif you need any in future:hphones:



best wishes

j7

[j7]

ohh and wot sort of internal wire is that? audio note silver fairy wire? or the VDH stuff

j7

[Chops54]

I do like to see a job well done and that's well done. Love the micrometer!

Si.

[zharca]

Hi, that’s the Audio Note wire with Michell tags. The wire is awful stuff to work with but I’ve learned a couple of tricks:
- never, ever leave it lying around loose. I got hold of some of those medical tweezers that are closed, not open, and they are a big help handling this stuff.
- Strip it with paint stripper, not hot iron, otherwise you get bits of burnt polywatzit in the solder or no joint at all.
These arms are dead easy to wire compared to normal ‘co you just take the armtube off and do it in two separate stages.

Have you used the Michell tags? Really great, made from solid rather than bent strip with a beautiful little split expanding sockets and a little cylinder for the wire Silver plated. Stupid expensive though at nearly £13 a set.


Apart from the micrometer bit, this one’s made from “production� parts so the performance should be consistent. The idea is that someone can put one together in a couple of hours with not much more than a screwdriver. About 18 months ago I made little jigs and a run of ten sets of parts. Took ages, and I’ve still got five of them! I’d been selling the kits for £200 including about £40 worth of ceramic bearings, so I ain’t gonna get rich! :X

I'm thinking that this might need a little more damping in the vertical plane and I'm not sure what to do: lower the weight CG (easyish) load the bearings up a bit (dunno) or use silicon damping.
Any views on this?

[j7]

hi jeff

yea ive got the audio note uk stuff...as well as the audio note japen kondo wire...its much thicker and deff easyer to solder

have you tryed the cardas ppce easy slip on gold tags?

ive tryed the michell cart tags...yes nice but as you say expensive

have you tryed the arm with the hifi news test record? its got the resonance rate test tracks...might help you see how the arm performes horizontal and vertical

[zharca]

Hi, yes i used the HFN record to get a guide to the resonant frequencies and the vertical came out at around 14Hz. It calculates at about 13.6 with the 30cu Music Maker. I reckon this is a bit high.
The arm's built with more inertia and damping in the horizontal plane 'cos I've been getting into bias compensation and the horizontal resonance is a little less and very well damped - just about what I want. I want a little bit of mismatch for following warps, but I think a little more damping might be an improvement.

What wire do you usually use for your rebuilds? I can hear a difference between Audio Note and Van den Hul, but it's damn expensive at nearly £50 an arm.

[thrunobulaxx]

Have to agree thats a lovely thing, i saw something very like it for sale on ebay a few weeks back, but i dont think he had onlydrilled the wand tecno style, not on top, he had replaced all the plastic with s/steel and aluminium.

Did you take apart a perfectly good micrometer for the VTA adjuster, it seems to lack the ratchet knob from the end, is it a moore and wright micrometer btw.:nerd:

anyway you have gone and put idea`s in my head,

I might be wanting one of those RB250`s jonnie;), if i start messing with mine i wont be able to play any vinyl untill its sorted.

[j7]

zharca wrote:
Hi, yes i used the HFN record to get a guide to the resonant frequencies and the vertical came out at around 14Hz. It calculates at about 13.6 with the 30cu Music Maker. I reckon this is a bit high.
The arm's built with more inertia and damping in the horizontal plane 'cos I've been getting into bias compensation and the horizontal resonance is a little less and very well damped - just about what I want. I want a little bit of mismatch for following warps, but I think a little more damping might be an improvement.

What wire do you usually use for your rebuilds? I can hear a difference between Audio Note and Van den Hul, but it's damn expensive at nearly £50 an arm.


I wonder if you tryfiddling with themassof the arm tube would this help?



i normally use the cardas 33ga ofc copper litz...although nothing comes close to the audio note uk wire for thinness

bw

j7

[zharca]

thrunobulaxx wrote:

Have to agree thats a lovely thing, i saw something very like it for sale on ebay a few weeks back, but i dont think he had onlyÂ!drilled the wand tecno style, not on top, he had replaced all the plastic with s/steel and aluminium.

Did you take apart a perfectly good micrometer for the VTA adjuster, it seems to lack the ratchet knob from the end, is it a moore and wright micrometer btw.:nerd:

anyway you have gone and put idea`s in my head,

I might be wanting one of those RB250`s jonnie;), if i start messing with mine i wont be able to play any vinyl untill its sorted.


I use micrometer heads which are ready to go. There are lots of NOS ones around now that everyone's gone digital. Like these on Ebay rigt now
29022086640
They were always available with/without the ratchet end.
The accuracy is stupid overkill but it does mean you can go up/down 1mm to try it and then go back to exactly the original setting and it's smooth enough to adjust on the fly.

It's not just a polish up job, all the bearing carriers and bearings are different. All that stays from the original is the armtube and arm lift. By accident I've arrived at the same kind of "decoupled" bearings as the OL designs, where the Rega, especially in the base has, I think, the bearings pretty well coupled straight into the armbord.

Johnnie: I was trying to avoid more mass but I usually run that cartridge with one of those isolator things which is going to add at least a couple of grammes right out at the headshell. I think I might stick that back on before mesing around any more.

[j7]

lo m8

you could try about 2-3 grams on the headshell with blue tac...its quick and easy to test with :)

[zharca]

Hi, that's just about the weight of the isolator, which should do the trick.
I tried the arm out without it first because it decouples the cartridge an confuses measurements. The little thing actually works!

[The Professor]

looks like a top job, really nice finish, except....and i know why you kept it, but the plastic ar rest looks so out of place, the rest of it looks good enough to be in a jewelers window

[thrunobulaxx]

Any chance of a close up of the piller/bearing end Jeff ? :evilgrin:

[j7]

thrunobulaxx wrote:
Any chance of a close up of the piller/bearing end Jeff ? :evilgrin:
call the copyright police :666gr:

[zharca]

Hi thrunobulaxx,
There are pics of the parts here:

www.audiomods.co.uk/armkits.html

I realise now that I got lucky with this 'cos one of the main issues with the Regas is that the base that holds the arm to the armboard also holds the bearings. Nasty turntable coupling. By mounting the bearings on their own carrier, I broke the loop. Never even figured out what I'd done for ages.
Duh.

Plastic arm rest: real complicated little bit to make. One guy in America who has one of these is a piano restorer and he's made himself a lovely little ebony one.

Johnnie: I don't mind publishing pics or even dimensions, 'cos I know how damned long it takes to make one!

[The Professor]

zharca wrote:

Plastic arm rest: real complicated little bit to make. One guy in America who has one of these is a piano restorer and he's made himself a lovely little ebony one.




hey i think your arm looks terrific, especially the bullet holes where pre modified it was probably shot to put it out of it's misery :D

No seriously I do understand why you use it, it only stands out because the rest of the arm is (to quote J7) godlike!!

Take a look at the clearaudio Unify arm rest, neat effective and well within your talents as a fabricator.

[zharca]

Hi Prof,
On "mine", the one I took off, I made a combined rest/lift using the Rega lift base, but this arm was supposed to be straight "kit" parts that anyone could put together with a couple of screwdrivers. If I do keep it, I might make something nicer. It's a bit of a givaway of its origins!

[thrunobulaxx]

zharca wrote:
Hi Prof,
On "mine", the one I took off, I made a combined rest/lift using the Rega lift base, but this arm was supposed to be straight "kit" parts that anyone could put together with a couple of screwdrivers. If I do keep it, I might make something nicer. It's a bit of a givaway of its origins!


I have seen arm rests for rega1 made in stainless, anyway the big givaway is the rega wand, there is nothing quite lkie it, thanks for the link jeff, i might nick a few ideas, but only for my own diy project, ;)

[j7]

the arm rest:
why reinvent the wheel?
its perfet and well made

i love em

[The Professor]

j7 wrote:

the arm rest:
why reinvent the wheel?
its perfet and well made

i love em

you though have no sense of style, of the aesthetic :P

[j7]

thats not ture!!!
i had some anaesthetic at the dentists once :)

[The Professor]

j7 wrote:
thats not ture!!!
i had some anaesthetic at the dentists once :)

aye and yer taste has been numbed ever since.

[zharca]

Well, here's another one going out.
This time it gets Van den Hul wire, which is real easy to work with compared to the Audio Note stuff. Just as well really, 'cos I need to practice as I've been given a little bag full of real Kondo wire for the next one, which is probably worth more than my whole system :shock:

http://www.audiomods.co.uk/images/rossarm3web.jpg

I'm pleased with this arm because all the micrometer bits are now "productionised", which really means I can make five the same. Bugger to make though as the top and bottom plates and the mountings and slidey bit all have to assemble to well within .001" to avoid locking up.

http://www.audiomods.co.uk/images/rossarm2web.jpg

Now, the guy who is getting the arm had this kit from me a couple of weeks back, and he's got it up and running.

http://www.audiomods.co.uk/images/wholeKitWeb.jpg

Gonna be real embarrassing if his sounds better than the one I've built for him.

Yes, he did want the arm lift left on:)

[thrunobulaxx]

Whats the going rate for this arm Jeff? :o)

[zharca]

Hi, if you want put one together yourself, the kit is £195. That's the stuff in the bottom pic plus a few little widgety bits. Once you've prepared the arm tube how you like it, it takes around two hours to assemble.

I do a complete built-up one with all the arm mods tweaked for the customer's cartridge type for £260 exchange, ready to wire, and the micrometer vta adds another £75.

'Aint gonna get rich doing this!

I'd like to offer a loan one, but I'm flat out now trying to complete some and I ended up sending out the first one in this thread to keep up.

[j7]

the parts look looovely

[zharca]

Thanks!
The chap is picking up the finished arm on Tuesday. On the one he's made up from a kit, he left the black paint on and drilled a row of holes underneath, Michell style. The kit one is done with some copper Litz wire and the fully built one with classy Van den Hul.

I've learned a new trick:
Your turntable oil is terrific for the ceramic bearings in these ams. I put the bearings in a little plastic tube along with some oil, then hang the tube in an ultrasonic cleaner. Shakes the air out and the oil gets right into the bearings. They set up absolutely play-free and sooo smooth. :D

[j7]

the oil is godlike:)

[thrunobulaxx]

j7 wrote:
the oil is godlike:)
What part of him do you drain it out off:666gr:

[j7]

thrunobulaxx wrote:
j7 wrote:
the oil is godlike:)
What part of him do you drain it out off:666gr:
heheh its his number 1 outlet :P

[thrunobulaxx]

j7 wrote:
thrunobulaxx wrote:
j7 wrote:
the oil is godlike:)
What part of him do you drain it out off:666gr:
heheh its his number 1 outlet :P
Just as well its not his No2 then.:D

[j7]

hehehh yes good point:)

[thrunobulaxx]

j7 wrote:
hehehh yes good point:)

Take no notice of me tonite, i have a few bottles of Cobra, i`m celebrating something i`m prolly gonna do tonite:666gr:

And its not the old in and out.;)

[j7]

lolol
i dare not ask any more then:)

[thrunobulaxx]

j7 wrote:
lolol
i dare not ask any more then:)
No, its a secret :D

[zharca]

Well, that arm went to it's new owner this week, and he happens to be a guy with rather a lot of turntables as well as a passion for Grado cartridges so, for the first time, i have a direct comparison 'cos he was able to set up four identical Grado signatures with:

Origin Live RB250
Michell Techno arm
er, (I don't like to mention this), standard RB250 with J7 set up and rewire.

and mine.

Mine won by a big margin.
:):):):):):):):):):):)


...only his opinion, mind.

He's gonna put his MusicMaker III on that one and he's ordered another arm.
chuffed or what?

[eddie spaghetti]

Nice one Jeff.

Just dont tell j7 :scared:

[j7]

zharca wrote:
Origin Live RB250
Michell Techno arm
er, (I don't like to mention this), standard RB250 with J7 set up and rewire.

and mine.

Mine won by a big margin.
:):):):):):):):):):):)


...only his opinion, mind.



would be great to hearcustomers views on the above best rega modders...esp if they have the 4 arms on the same turntable with the same cart...

interesting reading im sure

all my work on regas is very special...while they may not have the adjustablity of jeffs vtf...manycustomers dont want to fiddle withthere setup...once setup up and tightend down solid:pirate:

and maybe there is some hifi mag out there that could test the arms in the proper manner?:^



heheh

bw

j7

[zharca]

Hi, yes I'd like to see that, especially if I could get some accelerometer readings out of it.

What other candidates would there be?

Also, don't forget that the "standard" arm I mentioned above doesn't have any of your armtube or weight mods. And yes, yours are special. I get really annoyed by all the Internet geeks who talk about taking these things apart. Having stripped quite a lot of them, I know I'd never even try to put one back together the way it came and expect it to work.

Do you reckon Rega have "reference" specimens like the BBC used to do with their speakers?

[j7]

lo jeff

yours are special too m8 :)

i think the 4 best mod jobbers are OL and Technoarm plus your own arm and the AO versions (plus theres moth and a whole load of other badged versions)

hard to say what the results would be from the electrical tests...and esp the listening tests...some 1 like hifi World mag have the equipment and skills to unders stand the results

i see so many differant bearing tensions from the factory arms...seems like they have a number of assemblers...and over the months and yesr they get better at buliding the arms
not sure they have a referance arm to work from...i guess they are taught to set the free play in the bearings by practice

i have seen a rb250 cut in half as a dealer selling tool...showing all the parts inside--was 1 on ebay a few months ago

but it cant be easy to asemble them quickly..something 20 mins ive heard they get to make the arm up

bw
j7

[zharca]

Hi,
as a matter of fact I've just been defending the Michell weight as a clever bit of work over on Vinyl Engine:
http://www.vinylengine.com/phpBB2/viewtopic.php?p=80811#8081
i'm probably just about to get stuffed for it :D

Cut an RB250 in half as a sales tool? :shock:
Who'd ever buy one once they'd actually seen what's inside?

[j7]

zharca wrote:
Hi,
as a matter of fact I've just been defending the Michell weight as a clever bit of work over on Vinyl Engine:
http://www.vinylengine.com/phpBB2/viewtopic.php?p=80811#8081
i'm probably just about to get stuffed for it :D

Cut an RB250 in half as a sales tool? :shock:
Who'd ever buy one once they'd actually seen what's inside?

ive just thrown my 2p worth on the ve thread:pirate:

yea a sales tool,,, maybe it would be best kept high on a shelf :)... i been thinking tho ...i would love a walk round the factory to see how they manage to make so many...maybe 1 day ill get there

bw

j7

[zharca]

Hi, your insight into coupled/decoupled weight is really good.

Gave me a thought:
The weight fixes a bit like the OL style so, if I just include two lengths of stub fixing bolt and a little "O" ring, owners can switch between the two, like this:

http://www.audiomods.co.uk/images/stub-1.jpg

I've been betting on coupled, but they could listen and decide.

As for low-cg weights, I've sorta reached a compromise. If the cartridge is heavy (and I figure the heavy ones are mostly low-compliance) then I stick on a big "fine adjustment" weight, mounted low, which drops the cg without having to totally rework the main weight. Change your cartridge for a higher-compliance one, get a little weight. Sorted. :)