How Come New Tables Never Have S-Type Arms on Them?

[thebes]

I've noticed that virtually all new tables, weather high buck-or-low, never have an S-style arm.  Only one I could still find being made is by SME.

 

Back in the day these were massively popular, particularly on both cheap and quality Japanese tables.

 

I do know that they are way to effectively lengthen the arm while still keeping to rigid space requirements, but there were supposed to be other benefits to them, such as resonance etc.

 

So what gives?

[russ69]

Just a guess but the longer the arm the lower the resonant frequency. The idea is to get the arm to resonate above the audio band.

[Schu]

I don't think the Micro Seiki's ever had S curves.

 

lately the 12" arm has become very popular... but I still think it's 12 inches in length from pivot to needle regardless if the arm is physically 15 inches long and bent like a pretzel.

 

that is an interesting question though...

Edited December 2, 2014 by Schu

[Schu]

I take that post back... MS did have bent arms.

 

 

but it looks to be more for cartridge orientation versus lengthening effect.

[Tarheel]

What Russ said.

 

Micro Seiki MA-303, 505. DD-6 all had "S" shaped arms. 

[Travis In Austin]

Simple geometry my dear boy.  To save space. If you follow the angle of a straight arm backward in a straight line, you'll see that it puts the pivot point further off to the right (while viewing from the front). But bent, the pivot can be nearer the platter. It was a matter of design function.  However, it does mean that the "pull" of the stylus in the groove is now being applied at an angle to the pivot point, instead of directly. This creates torque on the pivot, and that torque is the reason for the "anti-skate" screw adjustment you see on tables that typically came with  S-shaped tone arms.

 

They started, I believe, with Technics tables.  They went out of favor because the S-shape required a higher mass (thicker tube to make the S), as well as the and "anti-skate" knob adjustment.

 

Travis 

[thebes]

Thanks Travis. Very informative post.  Still, though, and not to be contrary,  many, if not most, straight arms employ an anti-skate.  The Rega line (RB 300 etc.) comes to mind. Now weather they are actually needed on a straight arm, or they are there as a fashion statement, I leave to others.

 

Although, on second thought, whenever, I set finish setting up a cart, I also check channel balance with a test record, and without the anti-skate there is  a decided bias towards the left (inner groove) channel.

 

Also, I don't think space requirements have gone away and there are a whole lotta people into 12 inch arms, especially at the high end.  A s-shape on a 12 inch arm would shrink it overall size quite a bit. And with modern graphite materials, not to mention aerospace ceramics, weight should no longer be a factor in the designing a tonearm.

 

But then again, too light an arm and you get into high compliance carts, and then...

 

I think I'm getting a massive headache.

[Travis In Austin]

I didn't state the anti-skate part correctly.  I believe all tonearms, except tangential required an anti-skate device of some sort.  The s-shape tonearms seemed to do it with a spring device that was controlled by a knob which added or reduced spring tension.

 

My Vector, SME, Hadcock arms all use a counter-weight, as opposed to a spring, the theory being you don't want that aspect coupled to the arm board, but someone who knows more about the early SME arms would know more about that aspect.  An S shape gives you a longer effective length, and space advantages, at the cost of more mass and a spring anti-skate.  

 

You can still buy one new off the shelf if you want, not Technics, but Pioneer looks like they have copied their design.

 

http://www.pioneerelectronics.com/PUSA/DJ/Turntable/PLX-1000

[LarryC]

Hi Travis -- I didn't know you had a Basis Vector.  Which arm do you prefer?  Still using the Transfiguration?

 

I have only my usual gut instincts -- arms with the least sense of resistance to rotation around the axis, which I attribute to very low moments of inertia in arms like the current SME, feel like they should sound great and track well because they give the cart a very nice, free-feeling ride the groove.  

 

However, against that, the Vector and Basis clamp combo IMExperience sound exceptional and track extremely well.  Maybe the strong damping?

Edited December 3, 2014 by LarryC

[Travis In Austin]

Hi Travis -- I didn't know you had a Basis Vector.  Which arm do you prefer?

I got the Vector about a month or so after I heard yours and Gary's for the first time.

You called the Transfig distributor and he knew my dealer and he gave me a great trade in deal.

So all thanks to you on the Vector/Transfig Combo

Edited December 4, 2014 by dwilawyer

[Travis In Austin]

Hi Travis -- I didn't know you had a Basis Vector.  Which arm do you prefer?  Still using the Transfiguration?

Here is the link to the reviews and the story about you asking the distributor to send a couple if Transfigs to my Dealer

 

Edit:  2nd try at posting that link:  https://community.klipsch.com/index.php?/topic/85166-cartridge-auditions-part-deaux-photos/?hl=%2Btransfiguration+%2Bvector

Edited December 4, 2014 by dwilawyer

[thebes]

Thanks again Travis, very informative. The Pioneer table you point to is a DJ table, and I can't recall why, but there are some particular advantages for DJ's using a s-type tonearm.

 

I guess maybe the debate over the straight-arm versus-shape were maybe a bit overblown back-in-the-day.  I do recall passionate camps, sorta like Apple versus Microsoft today, extolling the virtues of their configuration of choice. 

 

I guess the straights won.

 

Oh.  Maybe the makings of a little tale filled with double entendres about the their shapes.  Or their inclination.

 

Yes the straight arms advocates drank scotch and rooted for the Bills, but those serpentine boys drank wine and hung out at the YMCA,

 

Ponder, ponder.

[Kent T]

I own one J-Shaped tonearm and one S-Shaped tonearm. SME/Ortofon/JIS headshell options a necessity for me. The main turntable in use is my Technics SP-25 motor unit/Audio-Technica ATP 16=T 12" transcription tonearm and my cartridge options mounted, aligned, and ready for action. Since I play a wide variety of records from differing era and am a broadcast engineer and archivist, this is my working setup. My other turntable is my Pioneer PL 518 which is in the bedroom.