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alb
06-05-2009, 07:33
Twenty odd years of not playing vinyl have come to an end.
Here's a few pics of my homebrew arm nearing completion. It's a simplified version of the Well Tempered arm.
It had it's first outing last night and managed to play several albums without a hiccup, so i guess it's worth developing further, or at least tidying up.

My last vinyl setup was a Linn Axis/dodgy Akito/K5 i think, and that was some considerable time ago. This one is definitely nicer to listen to, but it's in a totally different system so i can't really judge it's worth at the moment.

The armtube is 8mm carbon fibre, strengthened with brass tube and epoxy putty at the headshell end. The gantry bits are 6mm carbon held together by part of a "Helping Hands" thingy. The pulley is made from cheap alloy collets from a model shop and some washers. All suspended on one length of 8lb fishing line. Damping fluid is STP. Arm base is Meranti mahoghany.


[http://www.picstation.net/image-817B_4A01C863.jpg (http://www.picstation.net/share-817B_4A01C863.html)
http://www.picstation.net/image-45DB_4A01C863.jpg (http://www.picstation.net/share-45DB_4A01C863.html)
http://www.picstation.net/image-81A7_4A01C863.jpg (http://www.picstation.net/share-81A7_4A01C863.html)

Spectral Morn
06-05-2009, 08:04
Hi Alb

Can you resize your photo to 1024 X768 please current size is wayyyyyyyyy to big.

Thanks D S D L

alb
06-05-2009, 08:32
No probs. Didn't turn out that big on another forum, so didn't expect it.
Delete this thread if you will and i'll start again later.

Marco
06-05-2009, 08:33
No need to delete it, just edit it :)

Marco.

DSJR
06-05-2009, 13:39
Looks good to me. make sure the GL75 main bearing isn't wobbling and is properly lubricated.

alb
06-05-2009, 16:21
DSJR.

Yes, i don't like anything wobbly either.:)
The bearing has been stripped and cleaned, and i fitted new bushes while i was at it. Still very much running in.

Marco
06-05-2009, 16:23
Looks nice, Al. I like Lencos - there should be a fair bit of potential still to explore with it :)

Marco.

pure sound
06-05-2009, 18:18
I made a home made Well Tempered arm many years ago using a Mayware arm. I recall having a good deal of fun playing with the shape of the paddle and the viscosity of the 'fluid'. There were certainly some advantages in the removal of bearing 'chatter' that I was used to with other arms I had at the time. However, getting the paddle/fluid combination stiff enough to give really good bass but still fluid enough to leave the arm usable (ie for cueing etc) proved to be beyond me & I went back to the conventionally pivoted arm with bearings.

I've always run into the same issue with the air bearing LT arms I've tried and listened to. The bass performance has always been compromised.

Marco
06-05-2009, 18:54
Interesting, Guy.

I've always thought that tangential, air-bearing, arms knock spots off of pivoted arms in terms of 'accuracy', particularly with voices and midrange detail and a general lack of perceived distortion, but felt that something was still missing, musically... Perhaps it's like you say and that they lack authority in the bass?

I've only heard a couple of examples, certainly none in my system, so therefore haven't been able to notice that discrepancy so far in great detail.

Marco.

alb
06-05-2009, 21:21
I made a home made Well Tempered arm many years ago using a Mayware arm

I also made one around 25 years ago. I used an arm from a cheapish Rotel deck with some success. It used STP for the damping fluid, as does this one. So in a way i'm just revisiting my past.
Judging by the sound it's currently making, things have evolved a bit since then.
As for the bass, well it's good enough for me. Until i get a reality check from listening to someone elses setup.:)

Marco
06-05-2009, 21:48
LOL. Bring it round, Al, and we'll compare it to the Techy! ;)

Marco.

alb
07-05-2009, 06:29
Bring it round, Al, and we'll compare it to the Techy!



Now there's an idea!
But first i need to sort out one or two niggling issues that didn't become apparent while building it.

But how does one compare....

Sound Hi-fi-modified MK5G Technics SL-1210 with Time Step PSU, Jelco SA-750D (with Jelco heavy counterweight) fitted with NOS Audio Technica LT-12 headshell (Fidelity Research S/5 vintage headshell also used) and Ortofon LW1000S 'Super High Purity' Silver Lead Wire/Denon DL-103SA, (DL-103R and vintage Shure M3D also in use). Auditorium 23 MC step-up transformer & Denon HA-500 MC head amp.

with

GL75 with Heath Robinson dangly type arm, wired with Litz of Ebay cable. Shure M75ED, 5 EMO phono stage of unknown pedigree.

I think the evidence strongly favours one more than the other.
Mind you... i do have a brand new stylus.

pure sound
07-05-2009, 07:07
I ended up with STP too but did also try washing up liquid, syrup and some lump free strawberry jam!


there were alot of experiments going on in this pic!
http://i254.photobucket.com/albums/hh107/pure_sound/Flyingbedsteadarmlr.jpg

Marco
07-05-2009, 08:02
Now there's an idea!
But first i need to sort out one or two niggling issues that didn't become apparent while building it.

But how does one compare....

Sound Hi-fi-modified MK5G Technics SL-1210 with Time Step PSU, Jelco SA-750D (with Jelco heavy counterweight) fitted with NOS Audio Technica LT-12 headshell (Fidelity Research S/5 vintage headshell also used) and Ortofon LW1000S 'Super High Purity' Silver Lead Wire/Denon DL-103SA, (DL-103R and vintage Shure M3D also in use). Auditorium 23 MC step-up transformer & Denon HA-500 MC head amp.

with

GL75 with Heath Robinson dangly type arm, wired with Litz of Ebay cable. Shure M75ED, 5 EMO phono stage of unknown pedigree.

I think the evidence strongly favours one more than the other.
Mind you... i do have a brand new stylus.

LOL!

Well, I'd like to hear a Lenco in my system as that's one pleasure I haven't had so far. We could also try one of my nice cartridges on your deck and see how it responds to it ;)

I had an M75ED, and it's actually a bloody good cartridge, although perhaps just a little on the 'safe' side of neutral, as were most Shure cartridges of its era, but it's nicely detailed and musical sounding with a 'warm' tone and miles apart from the artificially 'pumped up' sound of many modern MMs. Are you tracking it at 1.4g? I found this optimal.

It would be interesting to fit the M3D or 103SA to the arm on your Lenco (with some added headshell mass) and simply replace the 1210 with it in my existing system. The Croft has a superb phono stage in it, so that should reveal how much potential is in your deck :)

Just PM me and let me know when you're free and we'll sort out an evening. I'll ask Del to do her 'coffee special' :smoking:

Marco.

alb
07-05-2009, 08:51
I'm sure we can sort something out, but i think setting this arm up is a bit hit and miss. Thats why i need to make a few small changes.


Are you tracking it at 1.4g? I found this optimal.

Still experimenting here, its early days yet. Don't have the technology to measure exactly 1.4g yet, its somewhere near 1.25 at the mo.:)
Will try some different weights tonight.

Marco
07-05-2009, 09:12
Al, just use a cheap set of digital scales which you can get in Pound shops, and sit your stylus on them - does the job :)

Marco.

alb
09-05-2009, 11:25
Well i've taken the above advice, and got me some digi scales.
Previously i had used an antiquated Connoisseur balance to get somewhere near.
It wasn't all that near apparently.
What i thought was about 1.4g, turned out to be 1.1g.:doh:
Anyway the old balance was rediculously hard to use. Trying to persuade a stylus you can hardly see, to sit centrally on a little pad the size of a drawing pin head, and stay there......

Marco
09-05-2009, 11:28
Nice one, Al. I presume then that the digi-scales are better?

Most importantly, does it sound any better now with the VFT corrrect? :)

Marco.

alb
09-05-2009, 14:19
I presume then that the digi-scales are better?

Well they're a lot easier, and i'm presuming that they are accurate.
As for the sound.......we'll have to wait till tonight. Too much happening at the mo.

I did manage to borrow a Cambridge Audio 540p phono thingy for a few days.
I found it a bit too polite sounding and lacking in impact. Nice device, wrong system maybe.
The EMO lets me hear more of whats on the record and presents it with a bit more enthusiasm.

Latest scores.
EMO 1 Cambridge Audio 0

Next up........... some sort of Pro- ject Phono box, hopefully.