building a tonearm

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Vinyl-ant
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Re: building a tonearm

Unread post by Vinyl-ant » Sat Apr 13, 2019 8:57 pm

Well I got it installed and had a cursory listen to it, and initial impressions are very promising.
I had to make a turret for it so it could be installed to run on the lenco. Which was a pain in the arse. I dug out an offcut from a plinth I did to make it

ImageCx unipivot mk testing by anthony cresswell, on Flickr

Cut a chunk out of this and turned a tower out of it which was an arse as neither ply, MDF or the particleboard core turns very well at all. It ate the chisels because of the heat build up, they had to be sharpened a couple of times while doing it.

ImageCx unipivot mk testing by anthony cresswell, on Flickr

Turned out ok though, but the install is not the greatest ever. It wants fitting to a deck properly. It was an absolute sod to get the cart adjusted so I had to settle for a close alignment as I simply couldn't see or get at the cart properly to do a proper job. But it suffices for testing.

I could also run both arms at the same time so I could do an A/B between them. So I did.

ImageCx unipivot mk testing by anthony cresswell, on Flickr

I then took the Goldring E3 cart off and fitted the AT150 sa to the CX so both arms had the same cart on.
Also had to bodge something fr the connector box to stand on and supported the long cables to it on the hook for the curtain tie-back....

ImageCx unipivot mk testing by anthony cresswell, on Flickr

So, impressions are that it has guts and that it is very stable for a unipivot, I think I got the weight distribution about right. It has a solid and dynamic sound to it, similar to the mk2 had but it seems to be more grippy than I remember that one being. I cant really say much about the treble as the cart alignment was out, but it seems ok so far. It also seems to image really rather well which was unexpected as the mk 2 one was ok but nothing special, and that its easy to place instruments in the image.

for want of a better word, it seems pretty musical, even if that is something of an amorphous term. One mans 'musical' is another mans 'coloured' or whatever other term someone cares to use.

But overall very promising. And not much hum even without an earth
BTE designs type 2 lenco, Audio Technica AT1100 AT150mlx (his), JVC QL-Y5F Audio Technica AT150sa (hers)
Benedict audio hothead mm phono stage
BTE designs type 1 custom khozmo shunt build passive pre,
PASS F5 dual mono Power amp
modified Philips cd371
Squeezebox classic
fane 15" sb speakers
BTE designs balanced power supply

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Latteman
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Re: building a tonearm

Unread post by Latteman » Sun Apr 14, 2019 9:02 am

Love the use of the curtain hook- actually a good idea for cables😂✅
RIP Doc
Analogue Source-
ARB Turntable & 10” dual pivot arm, Grado Reference Prestige 1 MI
Funk Firm Vector V, Acos modified tonearm, Grado Gold Prestige MI
Nva Phono 1 (external psu)
Digital Sources- Denon CEOL Piccolo, iPhone 6s
Amplification-NVA P50, A20 (x2), A60
Speakers- Diy BBCubes on Nva Stands;
Ls6, Ls5; SSP
Mini BMU

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Lindsayt
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Re: building a tonearm

Unread post by Lindsayt » Sun Apr 14, 2019 1:06 pm

How much did all the parts, plus any project specific tools for this arm project cost?
And roughly how many hours did it take?

Vinyl-ant
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Re: building a tonearm

Unread post by Vinyl-ant » Sun Apr 14, 2019 5:40 pm

Dunno on the cost, it was built with bar stock and other materials I already had including the wiring, connectors, cart pins, sockets, timber, etc.

Hours, probably about 10 ish so far of machining and re machining bits I cocked up or changed the design of, designing it, no idea, I've been kicking ideas around my head for a long while

I fitted it to the lenco properly today to get a proper idea of its sound quality, and to set it up properly too.

A load better than being on the turret and much easier to set the cart up correctly.

Took the AT1100 off the lenco and fitted the CX arm (a biking reference from the very first iteration of this arm) in its place. And put the at150 off the AT arm in the audiomods that's on the garrard. So I'm now comparing it with the audiomods arm rather than the AT1100.

I have run into an odd static problem, but other than that I'm rather pleased.
BTE designs type 2 lenco, Audio Technica AT1100 AT150mlx (his), JVC QL-Y5F Audio Technica AT150sa (hers)
Benedict audio hothead mm phono stage
BTE designs type 1 custom khozmo shunt build passive pre,
PASS F5 dual mono Power amp
modified Philips cd371
Squeezebox classic
fane 15" sb speakers
BTE designs balanced power supply

Vinyl-ant
Posts: 235
Joined: Sat Jul 01, 2017 12:51 pm
Location: South yorkshire
Contact:
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Re: building a tonearm

Unread post by Vinyl-ant » Mon Apr 15, 2019 3:05 pm

Proper install. Its on an arm board that was the original one for the deck when it was built, set up for an rb250. I used the same geometry so it fits properly on this board

ImageCx unipivot testing by anthony cresswell, on Flickr

Interestingly the static problem seems to have resolved itsself, then come back for some reason, and the more odd thing is that it is related to the rotation of the platter and not the motor.... set the platter spinning and the static crackles appear. turn the motor off and they stay. stop the platter by hand and they go away.... odd.

I need to understand why so i can solve the conundrum.

ImageCx unipivot testing by anthony cresswell, on Flickr

some earthing may sort this

ImageCx unipivot testing by anthony cresswell, on Flickr
BTE designs type 2 lenco, Audio Technica AT1100 AT150mlx (his), JVC QL-Y5F Audio Technica AT150sa (hers)
Benedict audio hothead mm phono stage
BTE designs type 1 custom khozmo shunt build passive pre,
PASS F5 dual mono Power amp
modified Philips cd371
Squeezebox classic
fane 15" sb speakers
BTE designs balanced power supply

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Dr Bunsen Honeydew
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Re: building a tonearm

Unread post by Dr Bunsen Honeydew » Mon Apr 15, 2019 3:15 pm

Is there a earthing wire between the headshell and the rest of the arm as you lose that by using wood in the arm tube. Or alternately use one of these before you play each record. https://www.ebay.co.uk/sch/i.html?_from ... acat=14969
Static is variable due to humidity, higher humidity makes it disperse.

Vinyl-ant
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Re: building a tonearm

Unread post by Vinyl-ant » Mon Apr 15, 2019 7:19 pm

No earth's at all on it it the moment other than the green and blue
That's what I've been on with today, trying to find some more wire to alter the loom. Found some to do it, but got waylaid with some other stuff..
BTE designs type 2 lenco, Audio Technica AT1100 AT150mlx (his), JVC QL-Y5F Audio Technica AT150sa (hers)
Benedict audio hothead mm phono stage
BTE designs type 1 custom khozmo shunt build passive pre,
PASS F5 dual mono Power amp
modified Philips cd371
Squeezebox classic
fane 15" sb speakers
BTE designs balanced power supply

keepitsimplestupid
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Joined: Mon Feb 26, 2018 2:18 pm
Great Britain

Re: building a tonearm

Unread post by keepitsimplestupid » Mon Apr 15, 2019 7:55 pm

|Shoot me your address Ant I 'll stick the bits in the post for you.

Vinyl-ant
Posts: 235
Joined: Sat Jul 01, 2017 12:51 pm
Location: South yorkshire
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Re: building a tonearm

Unread post by Vinyl-ant » Tue Apr 16, 2019 8:52 pm

Been playing with some tin foil as screening to see if it stops the static problem, and it does. As you would expect.
So I'll need some screening inside the wooden part of the wand on the next update to it. Perhaps some small diameter brass tube, have to work out how to get it inside.... And make up a screened output cable for it
BTE designs type 2 lenco, Audio Technica AT1100 AT150mlx (his), JVC QL-Y5F Audio Technica AT150sa (hers)
Benedict audio hothead mm phono stage
BTE designs type 1 custom khozmo shunt build passive pre,
PASS F5 dual mono Power amp
modified Philips cd371
Squeezebox classic
fane 15" sb speakers
BTE designs balanced power supply

OrangeFixie
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Joined: Sat Apr 29, 2017 6:25 pm
Location: Bristol, UK.
Great Britain

Re: building a tonearm

Unread post by OrangeFixie » Wed Apr 17, 2019 9:40 am

That's an impressive bit of design and engineering, looks beautifully executed.

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