Linear tracker

[Gordon Steadman]

I've been watching a thread on DIY Audio and, as I've been pretty impressed with my little JVC, which sounds much better than it should. I thought I'd have a go.

I am only doing a sort of trial at this stage, to see if it will work at all. The original uses glass as guides but as I have some SS rod and tube, I'm using that for now. I have some bearings taken out of old hard disks and they are brilliant. Unfortunately they are too wide for this application but just balancing the arm on the carrier and tilting a fraction makes the arm slide down. I await some bearings from China - just hope they are free as these.

The tube has a slot cut in it and the bearings are going to rest inside the tube. I foolishly started the process in the workshop, using an angle grinder. Once I had put the fire out........

.......twitface managed to aim the sparks at an open tin of wire wool:eek:, it went OK.

Anyway, this is the first stage, the bearings might be some time. All good fun, lets hope it works or I might have to stick with boring old swing arms like wot most do.

https://farm8.staticflickr.com/7426/16279169168_56db6a4b58_o.jpg

[walpurgis]

Ah yes. Angle grinder conflagrations. I've set fire to my trousers and sweatshirt in the past, under the car cutting off rusted exhaust bolts. Quite entertaining. :D

The arm sound interesting Gordon. I'll be watching to see how you develop this. Good luck.

[The Barbarian]

Aye good luck :D

[paskinn]

I think parallel trackers have the potential to offer the finest sound, better than any pivoted arm. But they are very hard to get working well.....so good luck. It could be something very special.

[Gordon Steadman]

I think parallel trackers have the potential to offer the finest sound, better than any pivoted arm. But they are very hard to get working well.....so good luck. It could be something very special.

I have been discussing the idea with my brother in law who was a design engineer. If you have something made of metal, he probably designed the machine that made it. He is deeply unimpressed with the design that i am attempting:lol:. Strangely, this is no surprise to me. However, we have come up with an idea that doesn't appear to have been used before. Maybe it has but didn't work.

Anyway, he seems to think that it may well have commercial potential so I can't tell you anything about it:doh:.

So for the time being I will carry on with this one. When the bearings arrive I can get it working (if it will) as everything else is just about ready.

[Yomanze]

I was having a coffee the other day when some dude with zero protection decided to start cutting through metal pipes with an angle grinder. I was cringing, it stank, loud and not what you want when having a coffee at the local café in the morning!

Awesome project by the way, looks fun and heavy, so should should sound good!

[Yomanze]

I think parallel trackers have the potential to offer the finest sound, better than any pivoted arm. But they are very hard to get working well.....so good luck. It could be something very special.

I was going to comment about how linear arms are far from 'fuss free' and they need a tweaker's heart to get the best out of them.

[Gordon Steadman]

I was going to comment about how linear arms are far from 'fuss free' and they need a tweaker's heart to get the best out of them.

The thread on DIY Audio is running at around 200 pages:eek:

As someone who tends to be a bit 'fit and forget'. I do wonder why I am doing this. However, it keeps the brain ticking over these cold winter days.

[walpurgis]

I did contemplate trying to make a 'maglev' parallel tracker using neodimium magnets. But decided it would be very tricky to get right (if ever) and the 'floating' character would probably be a problem with secure and accurate tracking.

[awkwardbydesign]

I was going to comment about how linear arms are far from 'fuss free' and they need a tweaker's heart to get the best out of them.
Is that for lubrication, or as a pump?
BTW, I would like to try one, but an Oracle is not really suitable.

[Gordon Steadman]

I did contemplate trying to make a 'maglev' parallel tracker using neodimium magnets. But decided it would be very tricky to get right (if ever) and the 'floating' character would probably be a problem with secure and accurate tracking.

Hmmm.... ideas. I have just stripped out half a dozen old hard disks. The bearings are fantastic and the magnets.....:wow:

You need a big flat bladed screw driver to get them apart. I wonder.........

[walpurgis]

It may work in a 'V' arrangement, but you'd have to spread the magnetic field along a strip of steel/iron carrier without getting localised 'pulses' of field and then of course there's the mass of the magnets supporting the arm having effects on the cartridge cantilever, Not good I think.

[Gordon Steadman]

It may work in a 'V' arrangement, but you'd have to spread the magnetic field along a strip of steel/iron carrier without getting localised 'pulses' of field and then of course there's the mass of the magnets supporting the arm having effects on the cartridge cantilever, Not good I think.

Good to play with ideas though:)

[walpurgis]

Some parallel trackers have used rotating cylindrical carriers, as if keeps stiction at bay.

[Gordon Steadman]

Some parallel trackers have used rotating cylindrical carriers, as if keeps stiction at bay.

Mine is going to be as simple as I can make it!!

The one we are in the middle of inventing is going to use gravity in a clever way to help the movement so stiction shouldn't, in theory at least, be a problem. Re-inventing the wheel is hard work though:scratch:

[paskinn]

'Reinventing the wheel'.....indeed. Goldmund once produced a parallel tracker which ran on little tiny wheels along a track. They used in their ST4 model, which sounded quite superb. I think their bigger, more automated, designs used a similar principle. For instance the wonderful Goldmund reference has an arm like that. Shouldn't work, but it does! I heard one sounding glorious only a few days ago.
Then you have the air-bearing designs like Rockport and Air tangent (and Kuzma) and the Souther/Clearaudio design which seems to use gravity. The problem there is that the cantilever has to 'drag' the arm along the tube, which imposes heavy loads on the cartridge. Then you have to deal with the torque of the output leads....definitely a stimulating challenge.
However, get it right and, to my ears, you have a tremendous 'free' sounding soundstage and a sense of effortlessness. If you get the mass right, you get fine bass too. Should keep you out of harms way for a few months.

[Gordon Steadman]

'Reinventing the wheel'.....indeed. Goldmund once produced a parallel tracker which ran on little tiny wheels along a track. They used in their ST4 model, which sounded quite superb. I think their bigger, more automated, designs used a similar principle. For instance the wonderful Goldmund reference has an arm like that. Shouldn't work, but it does! I heard one sounding glorious only a few days ago.
Then you have the air-bearing designs like Rockport and Air tangent (and Kuzma) and the Souther/Clearaudio design which seems to use gravity. The problem there is that the cantilever has to 'drag' the arm along the tube, which imposes heavy loads on the cartridge. Then you have to deal with the torque of the output leads....definitely a stimulating challenge.
However, get it right and, to my ears, you have a tremendous 'free' sounding soundstage and a sense of effortlessness. If you get the mass right, you get fine bass too. Should keep you out of harms way for a few months.

My brother in law has been infected with my enthusiasm. He is the guy who is now 86 years old and still races go-karts and rides classic motor bikes. We discussed the final design of our new prototype last night and he is off to the shops today to get the parts and can't wait to get on with it!! I'm letting him do the critical bits as engineering is his thing.

The JVC is singing now. I got a new JICO stylus yesterday and it really is very good. I can't wait to get the parallel tracker on a really good deck.

[walpurgis]

The JVC is singing now. I got a new JICO stylus yesterday and it really is very good. I can't wait to get the parallel tracker on a really good deck.


What JVC is that Gordon?



By the way your little package arrived just now. Many thanks. I've got a little step down transformer that should suit it just fine.

[Gordon Steadman]

What JVC is that Gordon?



By the way your little package arrived just now. Many thanks. I've got a little step down transformer that should suit it just fine.

Hi Geoff,

Its an L-E22. Pretty lightweight and runs on 12 volts with a wall wart. It was this that set me thinking about the idea of a parallel tracker. The JICO stylus has made a big difference to the tracking, quite clean now.

Glad the Dual arrived, it will be interesting to hear how it works.

[walpurgis]

Hi Geoff,

Its an L-E22. Pretty lightweight and runs on 12 volts with a wall wart. It was this that set me thinking about the idea of a parallel tracker. The JICO stylus has made a big difference to the tracking, quite clean now.

Glad the Dual arrived, it will be interesting to hear how it works.

I don't know the L-E22.

I'll have a rummage for the transformer at the weekend and have a play with the Dual. Should keep me entertained for a while. :)

[Spectral Morn]

Is that for lubrication, or as a pump?
BTW, I would like to try one, but an Oracle is not really suitable.

Yes it is but much depends on the weight and arm board used. I have seen photos of Air Tangent used on a Delphi and I was able with my own design of armboard to use an Eminent Technology. The right side suspension pillar cap was removed in my case as the ET needed this removed to fit correctly.

Oracle can supply, if you don't already have them, springs of differing tensions which allows a heavy arm to be used.

The sound was sublime and I deeply regret selling it :mental: :doh:


Regards Neil

[YNWaN]

The Souther Clearaudio design uses small ball races running on either a rod or within a cylinder. the Goldmund used a carriage driven by a powered belt - on this was a pivoted arm (in both planes). You can't really use gravity as side forces on the cartridge would be massive - which is precisely why air bearing arms have to be very carefully levelled.

[Gordon Steadman]

The Souther Clearaudio design uses small ball races running on either a rod or within a cylinder. the Goldmund used a carriage driven by a powered belt - on this was a pivoted arm (in both planes). You can't really use gravity as side forces on the cartridge would be massive - which is precisely why air bearing arms have to be very carefully levelled.

Well actually, yes you can:eyebrows:........if you are very careful with a touch of genius (my BIL not me)

Watch this space!!

[YNWaN]

You build a working prototype - then we shall see.

[Gordon Steadman]

You build a working prototype - then we shall see.

That, of course, is the entire idea:eyebrows:

[Spectral Morn]

The Souther Clearaudio design uses small ball races running on either a rod or within a cylinder. the Goldmund used a carriage driven by a powered belt - on this was a pivoted arm (in both planes). You can't really use gravity as side forces on the cartridge would be massive - which is precisely why air bearing arms have to be very carefully levelled.

The souther tri Quartz was a total pig, that barely worked. It took Clearaudio ages to get it right after they bought Souther and brought that design in under their own brand name.


Regards Neil