DIY Schroeder Tonearm???

[konstantin]

Dear Mr. Schroeder,

It is very sad that you do not see DIY Audio things the way other designers do, like Nelson Pass to mention only one.


The reason of existence of the DIY Audio community is sharing of knowledge of the so called HI-END equipment, that are most of the times too overpriced (and many of us can not afford) and NOT to solve anyones financial problems.


It would be great if you could only share your knowlegde with the DIY Audio community instead of terrorise it with lawyers and courts. I bet that you started your business as a DIYer.


Regards K.


Keep an open mind. It helps. (I lent this from someone in here)

[fdegrove]

Hi,

It is very sad that you do not see DIY Audio things the way other designers do, like Nelson Pass to mention only one.

This maybe be true but the fields of operation are quite different, tonearms and amps are hardly comparable.
While I admire Nelson for his approach, I do not expect a tonearm designer to adopt the same attitude.
The markets are just too different.

It would be great if you could only share your knowlegde with the DIY Audio community instead of terrorise it with lawyers and courts. I bet that you started your business as a DIYer.

Yes, it would be great but it seems to me that your understanding of business is ....errrr.... a little limited.
I fail to see where Frank Schroeder threatened with lawyers, he said he had negative experiences in the past and I'm sure he's not the only one out there...

I often find myself in non-disclosure situations too, if I break that agreement I can just as well say goodbye to my future...

Surely it's up to Frank to decide whether he's willing to unveil anything about his design or not?

Crickey, count yourself lucky he responded at all.

You seem to take it for granted that any design out there falls into the public domain as long as it is for DIY purposes, unfortunately for you that is just not the case.

Frankly, I regret your response and if it were to be my designs I would refrain from any futher help.

I don't mean to sound harsh, just want you to look at things from a designers perspective, hope you don't mind.

Cheers,

[berlinta]

Dear Konstantin,
It was never my intention to terrorize anyone with my lawyers, nor, as I said before, do I have anything against the DIY community. As you correctly guessed I did start out as a DIYer - essentially true for 90% of the "real" high end companies.
I replied to mgreene in private explaining why/how previous negative experiences with other manufacturers have raised my caution levels, I prefer to refrain from public namecalling so don't make me elaborate on this any further.
I'll happily provide you with advice but please don't expect me to publish exact drawings, measurements, material sources,etc... As someone here had said: "we'd like to find out on our own" - after all isn't that where half of the fun is?

The topic of (over)pricing has been discussed many times on each and every audio forum. What it comes down to is that certain components are very service sensitive(turntables: matching, setup...) whereas others are less so(amps, cd-players). Believe me, very few people know how to set up a turntable so that it performs 100%. Most if not ALL distributors/dealers won't even touch a component that leaves the competition in the dust if the margin on it doesn't allow them to cover their expenses. Not going that route simply excludes the option to make Hifi a living.
And there are many more people out there who couldn't tell an amp from a tuner than those who debate the virtues of teflon versus cotton as an insulator.

BTW, which other commercial designers do you mean besides Nelson Pass who publish blue prints of their original/recent work on the net?

Frank(fdegrove) was right on the money(pun intended) that - not only in my case - agreements between me and other manufacturers/distributors exist whereby I just can't give out or even license my product to someone else because they depend on me as a supplier and also want to take advantage of the "exclusive" nature of the product(strong point in this industry). It might not be to my liking but that's the nature of the game.

Ask me questions about my arms - and no one has so far - and I'll answer them as thoroughly as it is possible - see above.

If I didn't have an open mind I'd be building gimballed arms ;-))

Cheers,

Frank Schröder

P.S.: I much prefer to comment on technical instead of business issues in the future.

[krishu]

Hi

@Frank Schröder

Here goes the first(?) technical question: We saw your arms having one ore two strings. (I know its everytime one string, but the arrangement looks like two...)
For the two string version I see the advantage of a low "bearing point" as well as I think it is more comfortable to replace a string. And the neodyms do not need to be drilled.
For the one string arrangement I see advantages in easier set-up etc.
I, personally, tend to build the two-string type because I expect it to be done easier. Any warnings? What chose you? why?
And: Do you want to tell us something about the string?

I noticed you using a different shape of magnet. I cannot really understand, why it would be worse using two cylindrical ones. Agreed, a ball magnet with the center exactly at the "bearing point" would be the best, especially when having warped records. But I see no changing VTF when turning the magnets around their identical axis.

@ all

Prices. Yes, some products are very overpriced. But one must pay not only the material. If someone wants/has to live from such a business, there are some things that must be paid: Development, distribution, office and workshop rent; machines, taxes and so on...
Recently I made that experience when lathing counterweights for Rega arms like Expressimo Audio does. It seems that they want a lot of money for just a piece of steel. But when I startded to lathe these weights by my own I understood....

MfG
Christian.

[berlinta]

Hello Christian,
The bearing point in the single thread version can be almost as low as in the two-thread arm. But the counterweight would then have to be only ever so slighly eccentric to avoid changing VTF when altering VTA(or when playing warped records).
The initial reason for the two-thread version was that in 1980 when I built the first such arm, no Neodym magnets were available to me and I had to use Samarium-Cobalt which takes up more space as you know. It is also more brittle and the two-thread design encloses(protects) the upper magnet entirely apart from offering more space for the magnet.
The single-thread design is not only simpler to set up, it also offers two, more crucial advantages:
a less mass-ive armwand meaning less energy storage(of energy fed by the cart into the armwand). This is a common problem with most unipivot arms(you need to mass load the bearing to avoid bearing chatter).
a shorter thread means less susceptability to airborne vibration, also less initial stretch.

The execution of the two-thread design is simpler though! When experimenting with different thread materials it makes it a lot easier to exchange threads.

Do not use a monofilament but one of the modern "super" fibers. The knots are the real problem since the surface of the new multifilaments is extremely hard and "slippery". If you're a fisherman you know which knots are best used in this application.

Two cylindrical magnets wouldn't be a problem - if only the suppliers would deliver "perfect" shape magnets. But, as you will find out, any imperfection(like a cylinder with a face that's, say, at an 88° angle to the vertical axis - should be 90° of course..) will result in a uneven distribution of fluxlines in the gap, aka uneven VTF and or azimuth. BTW, fluxline density is highest at the edges, not the center of the magnetic gap.

(A) semi-sphere or ball shaped magnet(s) on the other hand do(es)n't offer the same flux density(attracting force) - using magnets of the same volume.

About overpricing: You forgot to mention the cost of a patent. One needs to sell quite a few arms before only that expense is covered...

Hi Konstantin,
So how does your arm perform in comparison to what you were running before(which arm was that?)

All the best,

Frank Schröder

[konstantin]

Hello Frank,

I hope you understand that i did not meaned to offend you, but that lawyer/court thing sounded a little "heavy" in my ears.

I agree, let's stay in the technical part of the "game".


Regards K

[fdegrove]

Hi,

I hope you understand that i did not meaned to offend you, but that lawyer/court thing sounded a little "heavy" in my ears.

Don't worry about it, I think Frank Schroeder explained the why for his position.

I was just afraid you'd chased him away.

[krishu]

Hi

@Frank Schröder

Thank you for your explainations. If further questions emerge I will be back here and if not you'll see some pics of the results then.

Cheers
Christian

[konstantin]

Dear Mr. Schroeder,

The arm i used before the construction of the clone was a Moerch UP-4, which was easily "bitten" by the clone.

Well, the UP-4 was sold and a DP-6 is on the way.

I also made some comparison tests with Simon Yorke's unipivot with the same results.
I'm very curious to compare the clone "side by side" with an SME-V.



Best regards
K.

[hifidaddy]

Originally posted by konstantin

The arm i used before the construction of the clone was a Moerch UP-4, which was easily "bitten" by the clone.

Well, the UP-4 was sold and a DP-6 is on the way.

I also made some comparison tests with Simon Yorke's unipivot with the same results.
I'm very curious to compare the clone "side by side" with an SME-V.

Konstantin,

I am not Mr.Schroeder, but as you might have seen from my test report on TNT web site, I have some Pluto tonearms (I have an older 2A and a newer 8A) and I prefer listening to my Schroeder, though the Plutos have their own strong sides, especially in the bass region. I also once had an SME V. The Schroeder is way better than the SME. In fact I rate the SME V not much better than the Moerch UP4, which is an excellent affordable tonearm.

regards,
Hartmut