Curved and Straight Tonearms


Over the last 40 years I have owned 3 turntables. An entry level Dual from the '70's, a Denon DP-52F (which I still use in my office system) and a Rega P3-24 which I currently use in my main system. All of these turntables have had straight tonearms. I am planning on upgrading my Rega in the near future. Having started my research, I have noticed that some well reviewed turntables have curved 'arms. My question: What are the advantages/disadvantages of each, sonic or otherwise? Thanks for any input. 
ericsch
S shaped arms allow for a greater pivot point distance than a straight arm - so less tracking error....
The only straight tonearms are linear tracking tonearms, the rest of the tonearm with straight armtube have an offset angle of the headshell, so they are not actually straight, except for the very short ones like the ViV Lab for example.
Yes, I meant straight up to the headshell. Other than less tracking error, any other pros or cons?
The last time I looked,most high end tables come with a straight arm. I don’t think it makes any difference,it’s all about the design of the arm. Take a look at this!
http://store.acousticsounds.com/index.cfm?get=results&start=1%20&CategoryID=111
I think the best way is to try the Audio Craft AC3000MC / AC4000MC with multiply armtubes of the different shapes. 
It looks like the OP is looking for a table that comes with an arm included. I doubt he is looking at a vintage separate arm!
S shaped arms allow for a greater pivot point distance than a straight arm - so less tracking error....
The pivot to stylus distance determines the degree of tracking error, and since the pivot to stylus distance is a straight line, different shapes of tonearms with the same pivot to stylus distance will trace the same arc.

The greatest advantage to a S or J shaped tonearm is it ability to be designed with a detachable headshell as the offset angle is built into the arm design
@yogiboy 
I doubt he is looking at a vintage separate arm!

I mean if someone would like to compare S vs. J on the same arm the Audio Craft and related stuff with removable artubes is a good option to understand which shape is the best for the owner. 

I have 2 "S" shaped tonearms and 4 "J" shaped tonearms and i can't say which one is better based just on the armtube design. 
@chakster
Gotcha!
 IMO,cartridge and arm matching is often overlooked when evaluating the performance of an arm! Do you agree?
My question was prompted by the TAS review of the Technics SL-1200G in their current issue. I'm looking for a table under $3500, not vintage. I like Rega products, but I want to be able to use different cartridges and adjust VTA without using shims. I currently use an Exact 2 in my Rega.

there are perfectly straight arms, but they're mostly used for DJ scratching.

the rest of arms as pointed prior either curved or with s-shaped tube.

Most DJ arms are "underhung" to aid in scratching, whereas straight tonearm with an offset headshell used for accurate audio replay are overhung. 
An S shape has the advantage of resonance reduction. The two bends add rigidity to vibration compared to a straight tube and flexural waves will be attenuated. Also a larger tube is more rigid than a small tube even if they weigh the same (tubes have good rigidity for their mass compared to a solid rod). Light weight straight tone arms have the increased risk of unwanted resonance due to standing resonance waves along the entire length.

Only advantage of straight is they are cheaper to build and can have lower mass for high compliance cartridges.
I have had both,  shoot,  I have both now.  Overall I agree with shadorne as far as curves contributing to resonance reduction and mass for high or low compliance cartridges.... Although,  I have heat shrinked and used interior dampening on light weight straight arms,  also with good results. 
Just thinking,  at one time,  I had my brothers Denon,  I believe that it was a DP60L... Might be wrong,  but I had it for about 2 months doing a few mods, 1 repair and some adjusting,  but this table had interchangeable arm tubes... a low mass straight arm and a medium mass s arm... both worked well.  At the time,  I didn't compare,  we exchanged them based on the cartridge. 
Why is it that most of today’s cost no object SOTA arms employ a straight arm tube. Where are the super "S" arms?
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@testpilot

Good question. While at it you could ask why are cheap plastic (acrylic) light weight turntables promoted over heavy plinth steel/wood traditional designs?

I think production and shipping cost has something to do with it...not sure if all the marketing hype about better sound is as real and tangible as all the production and shipping cost savings.

Like Harbeth light weight waffling speaker cabinets - I don’t buy into the hype but I do understand how a cheaper build and lowrr packaging and shipping cost is a big competitive advantage...
@shadorne
You have no idea what you are talking about. Harbeth and many other British monitors use the BBC thin wall design for a reason,and it’s not for a cheaper build ! Check it out!
http://www.grahamaudio.co.uk/technology/cabinets/
At your price point, you can consider going a refurbished Sota and start looking for a good condition Graham 2.2 arm or similar.  The Graham features VTA adjustment on-the-fly.  That is one of the biggest improvements in playback quality you can make.  You could also consider doing the same thing with a mid-priced Rega or other non-suspended table.  They may not be suitable for your installation, because it depends on how well isolated the table location might be.  Either way, you have a lot of excellent choices to consider.

Take your time, do as many auditions as you can, watch the postings here and most importantly, have fun!  Good luck & happy listening!
@yogiboy

Good points and a good article marketing the benefits of thin wall - a bit like the benefits of Rega light weight acrylic plinth and platters (in the case of Rega the sympathetic absorption of vinyl vibration is most effective when using an acrylic platter as the material is closer to the properties of the vinyl and like thin walled speakers we are expected to accept the argument that "more vibration" is "better as the material dissipates the energy")

So yes I am aware the thin wall speaker was initially designed for BBC for light weight and portability and then damped with bitumen to reduce the deleterious resonance effects and then the "magical" benefits of more resonance were discovered.

I buy the advantages of portability and light weight. I enjoy the fact my JBL PRX615M are great lightweight PA speakers (light cabinets with light neodymium magnets) that are easy to move around for my band.

However, I don’t buy their resonance arguments. Why use a bitumen damper if the resonance is not a problem? And I don’t accept the claim that the extra cabinet resonance is beneficial - all resonance should be avoided for ultimate fidelity as any resonance will change the timbre of the sound. And thick MDF built heavier speakers can have bitumen damping too - so logically when damped and heavily braced these should be even less resonant than a thin wall.

Of course "beneficial" could be construed not to mean high fidelity but desirable sound to listeners - a warmer tone perhaps or more euphonic sound - I accept that and I agree Harbeth have great mid range tone (it is more the lower frequencies that seem impacted by this thin wall type design - at least to my ear)

My two cents of course. Maybe I just prefer heavier TT and heavy speakers. Certainly you can get great sound from light weight designs: speakers like Harbeth or TT like Rega perform better than very many competive but heavier designs. However the necessary damping required tells me that designers must compensate for the tendency for light materials and thin walls to vibrate with their own characteristic resonances.
Somehow, the OP's actual question about pivoted tonearms with straight vs curved arm tubes (or "wands") got completely lost as the discussion turned to turntable and speaker mass.  But most of the main points were made.
(1) As others mentioned, if the arm tube is straight on a conventional pivoted tonearm, then the headshell offset angle must be incorporated into the headshell mount itself.  As a consequence, many such tonearms bear headshells that are permanently mounted. This was a trend in design meant to maximize ridgidity from pivot to cartridge.  A curved arm wand (J or S) will generally have a higher effective mass than a straight one of equal effective length, simply because the linear length of tubing will be greater compared to the straight version. A curved arm wand will more easily accommodate interchangeable headshells of many different types and weights, because the offset angle does not have to be incorporated into the headshell mount.  There are all sorts of ideas and hypotheses about which is better, straight vs J or S-shaped, some of them having to do with resonance and some having to do with weight distribution across the S or J shape and whether one should compensate for that.
(2) Someone mentioned "very short" tonearms, like the Viv.  The Viv (and the RS Labs RS-A1 tonearm, which preceded it) is an entirely different animal.  Conventional pivoted tonearms have a headshell offset at an angle solely in order to achieve two points of tangency of the cantilever to the groove across the playing surface of the LP, using any of several standard geometries (Baerwald, Lofgren, Stevenson, etc).  The Viv and the RS-A1 have no headshell offset angle. Thus they can achieve only one point on the surface of an LP where the cantilever will be tangent to the groove, and generally the tracking angle error is greater for the Viv and RS-A1 than for conventional tonearms, at any other point on the LP.  The trade-off is in skating force.  The Viv and the RS-A1 will still generate a skating force (except for that one point where there is tangency to the groove, where skating force = 0), but the skating force is not affected by headshell offset angle, since there is none.  Conventional tonearms NEVER are free of skating force, because even at those TWO points where the cantilever is tangent to the groove, there is still a skating force due to the headshell offset angle. From my personal experience with the RS-A1, "straight: tonearms (meaning those with no headshell offset) can sound really good, better than you would expect given the much larger tracking angle error of this type of tonearm.  
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Roy Gandy, designer and manufacturer of the game-changing Rega pickup arms, proselytizes that it is a straight wand which can be made stiffer than an S-shaped one. SME, whose arms in the 1960's and 70's (Series 2 and 3) were S-shaped, does the same.
What "game" was changed by Rega pick-up arms?
I agree that the modern trend is definitely in favor of straight pipes.
As some have already noted, s shaped arms tend be higher mass designs.  The choice of arm  (mass being a key issue) is generally dictated by cartridge matching (compliance), so you're usually nudged toward the curved camp or the straight camp by your cartridge.

Beyond that, there are enough other issues at play (bearing design, adjustability, etc) that the issue is IMO low priority (beyond aesthetics).
Dear @ericsch : In reality there is no true/real advantage on those kind of tonearms. The real advantage belongs to tonearm design and excecution quality levels of that design and that's all.

Pivot bearing type can be a difference. Unipivot against fix ones. I prefer fixed ones.

How many cartridges do you own?


Regards and enjoy the Music Not Distortions.
R.
Raul, based on what I have learned over the last few years, I would also prefer a fixed pivot.
I am the original owner of 2 Shure cartidges: V15 Type V-MR and V15 Type V, both with Jico styli. I use these on my Denon DP 52-F.
For my Rega, I have the Elys that came with the table and a newer Exact 2 that I use now.
Like I mentioned earlier in this thread, I like Rega, but I want to move to a table with adjustable VTA. 
BTW, thanks to all who responded, very enlightening. 
Sorry to disappoint you guys but properties like stiffness depend greatly on type of material, mechanical properties of the material, length to diameter ratio, you can't just say J shape better than straight pipe or vice versa.  
Same goes for resonance.  There seems to be a lot of misconceptions about resonance which works to the advantage of people that market "tweaks" and cones.  There is no way to tell which shape will be better. The resonant frequency of an arm tube will change when coupled with the headshell, cartridge, stylus, arm bearings and mount. The system (arm assembly) resonance is the all important parameter here.
Either can sound very good if matched to the rest and set up properly I believe but personally I’ve always had better luck with straight tonearms. But in practice fact of the matter is I’ve never had results with S arms like with straight and most quality tables these days use straight probably for good reason.

In the golden age of vinyl back in the 70s selling at Tech Hifi, Lafayette and Radio Shack I always levitated to tables with straight arms. Tracking was not nearly as reliable with massive S arm tables and carts. Often hard just to stay in the groove. Tracking a record is hard and mass and inertia is not your friend when it comes to tonearms with most records in practice. I prefered Thorens Philips and Linn over most Japanese tables with S arm.  Even Dual at comparable price points.  Maybe Micro Seiki......

I've gotten many years of listening pleasure out of a Linn Axis and even still a Dual 1264 with Goldring cart from 1981 still running in my second system.   Both straight arm. 

"In the golden age of vinyl back in the 70s selling at Tech Hifi, Lafayette and Radio Shack I always levitated to tables with straight arms. Tracking was not nearly as reliable with massive S arm tables and carts."

Perhaps the elegant and extremely effective SME "S" arms were overlooked? I recall one of the Stereophile sages declaring the SME Series III as his "gold standard" at the time.
Straight or curved really doesn't matter. What is most meaningful is how well any particular design is executed. I'd take a well-engineered "S" arm over a mediocre straight arm any day.

Dear @ericsch : I'm not an expert oon your Rega model but I know that exist an after market source where you can buy the VTA mechanism dedicated for your Rega tonearm.

Regards and enjoy the Music Not Distortions,
R.
S arms are usually higher mass, often used with MC cartridges

"straight" arms with offset headshells which are not removable pretty much defines all the many good/great tone arms I've heard or owned.

For no tracking error, and no inner groove distortion, great mids and highs, very little wear to LP's - but with bass lacking weight get a Souther/Clearaudio and be done with it.
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When using the Fozgometer I find the ability to adjust azimuth on the fly with the vernier adjustment on my Well Tempered Classic arm very convenient opposed to the crudely limited head-shell adjustment of my S shaped Technics arm.
If the azimuth cannot be fixed by the limited headshell adjustment, you really need to return the cart you bought, you have a cartridge problem not a tonearm problem.
I read Robert Greene's review of the SL1200G in TAS last night.  I own an SL1200GAE and have done so for about a year now.  Of course, it has an "S" arm on it.  I also own a VPI Prime with straight tube arms (2) and have owned this TT for about 2 years.  I also own another VPI HW19 fitted with an SME Series III, another "S" shaped arm and have owned this one since 1989.  Anyway, if anyone is interested I will try and offer some additional perspective on the matters under discussion to the already excellent points made.
OK, here goes.  Although it is correct to say that an "S" shaped tonearm often facilitates the incorporation of a removable head shell into the design, it is not axiomatic that this would be so.  Case in point, the SME Series III is an "S" arm which does not have this feature.  Rather it incorporates a similar interchangeable arm design to my Prime.  It is also problematic to make bold statements about bearing configurations.  For example, my Prime single pivot tonearm was recently modified and significantly improved sonically by the addition of a second pivot, developed by VPI.  The GAE has a double gimball bearing arrangement.  Using the same cartridge, the two TTs/arm combinations do sound somewhat different, but as to which is "better" or more "accurate" I cannot say. There will be those that make decisive statements about the merits of direct drive vs. belt drive, complete with golden ear claims about tone/pitch perfection and such, most if not all of which have been debunked over the years in repeated double blind tests.  My SL1200GAE does have very steady speed, is quiet and all that.  But my Prime, with it's heavy platter, excellent bearing and tripple belts, and aided by Phoenix Engineering Roadrunner Tachometer and Eagle PSU, is it's equal both measurably and sonically.  In short, these are two superb turntables and both sound terrific.  They are different ergonomically, with the GAE easier to setup and to use perhaps appealing to the record collector, the Prime perhaps appealing more to the true audiophile.  I am not sure which of these two TTs is the better of the two.  I am reminded of the wisdom of Bertrand Russell, "The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt."
So, who first promulgated that thought, Bertrand Russell or William Butler Yeats? In the Second Coming, written in 1919, Yeats wrote:
"The ceremony of innocence is drowned;
The best lack all conviction, while the worst
Are full of passionate intensity."

It doesn’t matter, really. We see evidence of the truth in these sentiments on a daily basis, emanating from the White House and its environs.


It is a sad commentary upon the times when we can't sort out definitively the pluses and minuses of a mature technology like tonearms, but have no trouble at all getting a bead on the emanations Tweeting from the White House.  Which is way off topic.  My apologies.
@billstevenson  Thanks for your thoughtful reply. My original question related to pros and cons of each type of arm and your comments are certainly in that vein. I know all of this can be very subjective and system/room dependent. I want to experiment a little with different cartridges and your "ease of use" comment relating to the Technics is something I need to consider. And please, to the group. I don't want to start a war of VPI versus Technics. I know VPI makes great tables. But, at my advanced age ease of use is a plus.   
There's no real advantage to curved arms. TT manufacturers began making them because the convenience of removable headshells allow for quick cartridge swaps and easy setting of the offset angle. The advantage is the ability to place the cartridge square in the headshell and achieve offset angle. Like many trends in turntable design, the bends give no appreciable advantage in resonance control. Another marketing gimmick that doesn't produce any discernable difference under real playback conditions.
What brf and Lewm said is correct... and now add helomech. 

No manufacturer would make a curved arm if the industry did not adopt the SME style headshell that has no offset angle. The ONLY reason to make a curved arm is to have the offset angle at the armwand since the headshell is a straight geometry. The SME 3 has detachable armwand instead of detachable headshell so they have to make the offset at the arm. Curved arm is a result of geometric necessity. If a curved arm sounds good, it is good not because is curved. The curved Alphason tonearm is made of one piece tube so they have to bend the arm to have the offset angle. Rega is also one piece but straight because the armtube is cast aluminum. Much of it is the result manufacturing process. Many curved arms with detachable headshell also have a side weight at one side of the bearing is because the uneven mass of curved arm needs to be balanced. Again, form follows function. Hey, I use curved arm with detachable headshell because I like having the option of changing out cartridges not because curved arm sounds better. 



The J and S shape tonearms (need to) use the so called ''lateral

balance'' weight in order to get equal pressure on both horizontal

bearings. The J kind is difficult to balance while the S can be

balanced by lifting up the front side of the TT and then moving the

later weight till the arm reach equilibrium postion. From this it  

follows (?) that stright tonearms can't be in equilibrium position

because one side of the bearings  get more pressure than the

other.

@nandric,

How does that apply to straight tonearms? Because of the slightest weight bias on one side of the cartridge end?