AudiogoN
Search Buy Sell Learn MyPage
 Learn > Forums > Analog > 1231176780  Start New Thread | Log In | Bookmark This
  Tonearm without off-set
Hi All

Just wanting to know if a straight 12 inch arm without off-set is a good idea.

Yes, the alignment is not as good as an off-set arm, but there's the advantage of having no anti-skate problems, and also probably less stress on the cantilever.

Any feedback from current users of non off-set arm would be fantastic, or any opinions you may want to share on this topic.

I have to make a decision which way to go, as the arm manufacturer can make both versions.
William62  (Threads | Answers | This Thread)

01-05-09
  Responses (1-15 of 15)
Click title to read one, or click date to read all below it.

01-05-09: Dougdeacon
You'd be better served by doing the opposite: retain the correct offset but consider deleting the antiskate mechanism.

1. The sonic benefits of highly accurate alignment are huge. Search this forum for "Mint" or "MintLP" protractor for a wealth of information and testimonials across a wide range of tonearms and cartridges. You'd be shortchanging yourself not to have the best possible alignment, which won't be feasible without a properly angled headshell.

2. The skating force on a 12 inch arm will be very low, so you'll need little if any antiskating. Many people play without it on shorter tonearms, despite larger offset angles, and your arm will need less (though it's somewhat cartridge dependent). Some, including me, have removed our antiskating mechanisms altogether, to good effect.

3. Unless you apply antiskating there's no more stress on the cantilever/suspension with an offset than without. Since you'll probably play with virtually zero antiskating, this shouldn't be a concern.

So:
- have the correct offset built into your new tonearm;
- consider asking the manufacturer to forget the antiskating mechanism altogether, or at least to make it easily removeable;
- procure a Mint protractor (or a Wally, if you can get one).

My $.02 (inflation adjusted of course).


Dougdeacon  (System | Reviews | Threads | Answers | This Thread)


01-05-09: Rauliruegas
Dear william62: As Doug point out: retain the correct offset.

The pivoted tonearm offset (along the length of the tonearm ) determine/help to put at minimum the tracking angle error, so if you want a pivoted non-offset tonearm then what you will obtain is a higher tracking error that means higher distortion ( between other things ) on the cartridge signal.

I think that what you want ( like any one else ) is to reproduce faithfull what is on the recording or at least to be nearer to the recording. The non-offset tonearm subject put you far away.

Regards and enjoy the music.
Raul.

Rauliruegas  (System | Reviews | Threads | Answers | This Thread)


01-06-09: Normansizemore
You dont mention if the arm will be straight, S shaped or a bananna congfiguration. Either way, a 12 inch arm is a jewell. I have a couple of audio friends, one who has a 12 inch straight arm with the head shell at the correct offset. He said (and I agree) that this lowers the mass when compared to an S shape or a bananna arm. He does not employ antiskate, but I can see that (as you are facing the turntable) the cantiliever of his cartridge pulls to the right as if the arm wants to 'skate' in towards the record label. When I see that, it makes me think that a little antiskate wouldn't be such a bad thing. I personally use it on my 9.25 inch Grace 747, but then I kinda need too as I don't have the additional tonearm length to dial it out.
I am envious! Wish I were having a 12 inch arm built!
Enjoy.
Norman

Normansizemore  (Threads | Answers | This Thread)


01-06-09: Johnbrown
You ask if the no-offset proposal is "a good idea", and yet, at least at VA, you seem determined to purchase one, despite all evidence that this is not, in fact, a "good idea".

If you're just looking for validation for this irrational concept, I doubt you'll find it either here or at VA. What's even more surprising is that any reputable tonearm manufacturer would build one for you, unless your goal was to be the dj 'scratcher' with the 'biggest, baddest, longest arm'.

Johnbrown  (Threads | Answers | This Thread)


01-06-09: William62
Johnbrown

"irrational concept"

We are among people who spends in excess of $50,000 on their hifi system. Some Like DD and Raul would probably be in the range of $250,000.

Some at AG buy 2 watt amplifiers that cost $25,000 and say a Garrard TT made in 1948 is better than a $30,000 SACD player. I could go on.

So if I do not think like you, I become irrational?

No I have not bought the arm, but is seriously thinking about it. By asking for opinions and discussion before any purchase means "validation" to you. You would be criticizing almost half of what is written in this forum. Isn't that what forums are for?

"unless your goal was to be the dj 'scratcher' with the 'biggest, baddest, longest arm'."

You don't have to belittle me because I do not agree with some of the people at VA or here.

So sorry I can't agree with you and make you happy.

Thanks for you post.

William62  (Threads | Answers | This Thread)


01-06-09: William62
Doug and Raul

Thanks for both of your very informative reply. I hold them in high regard.

After reading the huge thread that discusses anti-skate where both you and many others contributed, made me come to the conclusion that rather than to cure skate with anti-skate, we should look at avoiding designs that adds skate - such as an arm's off-set.

The option of a linear arm does not thrill me, and if I do go for an off-set arm, it should at least be 12 inch to reduce tangential tracking error.

This is where I am in my thoughts at the moment. I do have an ARO and a PU3 at the moment. will probably be also buying a Lab 47 RSA-1 too. So having this non off set arm is just something I am toying with to install in my DIY Lenco which will ultimately have at least two arms.

William62  (Threads | Answers | This Thread)


01-06-09: William62
it should at least be 12 inch to reduce tangential tracking error."
William62  (Threads | Answers | This Thread)


01-06-09: Johnbrown
William-

With apparently the same logic that you've used for your arm concept, you've missed my point. Comparing your odd tonearm strategy to someone's expensive stereo gear means nothing-it's like buying a Ferrari because you need a new toaster.

I'm trying to find the reason for your query both here and at VA. You ask if a straight, no-offset pivoting arm is "a good idea". It ain't-and you're unlikely to find anyone who will tell you that it is. And yet you're determined to proceed. Thus, I can only conclude that you're not really seeking any knowledge on the subject, you're either looking for a validation, which won't be forthcoming, or...well, I don't know, you just need something to do, I guess.

I'll change my tune if you can show me the math that will allow a straight, no-offset pivoting arm to have tracking error and distortion equal to or less than an arm with offset, and aligned with a Baerwald or Lofgren formula. Until then, feel free to ruin your records any way you choose, but don't expect me to support your ill-fated dream.

Johnbrown  (Threads | Answers | This Thread)


01-06-09: William62
Johnbrown

"but don't expect me to support your ill-fated dream."

None was asked for. It is just a bloody arm that we are discussing. I do not understand why you are so worked up about this. You want to kick my dog or something?

And regarding "math (sic)" logic, so how come some highly regarded contributors here removed their anti skate devise on their ET tone arm and not use them? There is no maths in that.

Some of us actually use our ears to determine what Maths can't explain.

Also if we are so dogmatic about perfect tangential alignment, we should never ever use any pivoted arm - off set or not. How much distortion is acceptable or discernible? Choosing by numbers is a worry when it comes to sound.

And in your opinion, it seems that the only criteria for a tone arm to sound good is to have perfect tangential alignment. There are other factors that can make a tone arm great sounding. And if you do not know already, all tone arms sound different regardless of perfect geometry or not.

Anyway, I respect your opinion and let's just say that you do not agree with me on this topic and perhaps many more.

Nice talking to you.

William62  (Threads | Answers | This Thread)


01-07-09: Thom_mackris
What Doug and Raul said ...

Look up the numbers on John Ellison's gift to analog-kind - his Baerwaald / Loefgren spreadsheet on the "Free Stuff" section of the Enjoy the Music website. This is Frank Schroeder's and my bible.

If you have trouble finding it, go to my Support Page, where I maintain a link to that section of the Enjoy the Music site.

Cheers,
Thom @ Galibier

Thom_mackris  (Threads | Answers | This Thread)


01-07-09: Thom_mackris
Hi William62,

One more thing ...

Removing the offset angle still leaves you with the decision as to whether to create overhang, underhang, or neither. You still need to arrive at an alignment strategy that minimizes tracing distortion for your chosen path (e.g. offset angle = 0).

While skating forces are very real, they are secondary to minimizing tracing distortion, and this is the genesis of the posts advising you to go by the numbers.

The math developed by Baerwaald, Loefgren, Stevenson, et. al. were all exercises in optimizing tracing distortion over various parts of the LP.

I have to admit that I've played only minimally with Loefgren, but my experiments with the Baerwaald Mint LP protractor (after being a two point protractor user for eons) was a revelation to me, Doug and countless others.

Now, strictly speaking, slapping a cartridge on a tonearm and randomly mounting it is an "alignment" and we can give it a name if we choose ("Joe the alignment").

After hearing the difference between "almost Baerwaald" (as in attempting it with a two point protractor) and an accurate Baerwaald (Mint LP arc protractor), I've gained more respect for the math developed by him.

Having said that, knock your socks off and have some fun. Why don't you make concentric, crescent shaped slots in your headshell that will allow pivot the cartridge from 0 degrees offset to the Baerwaald recommended number for your effective length? Then, you can prove this to your own satisfaction and report your findings.

Enjoy the journey,
Thom @ Galibier

Cheers,
Thom @ Galibier

Thom_mackris  (Threads | Answers | This Thread)


01-07-09: William62
Thanks Thom. I really enjoyed reading all your posts in AG.

Over the years I have owned or still own: Grace 707, Lenco, LE1, PU2, Alphason HRS100, Rega RB250, Well Tempered, PU3 and Aro. So I am not new to pivoted off-set arms or has anything against them.

You are absolutely right that tangential alignment accuracy is very important. I can hear the difference you mentioned. I even slotted my Aro head shell which only had two holes so that I get it perfect.

The thing that most interest me in trying non off-set straight arm (which is only one of the 3 arms that I am intending to use in my system), is the fact that the cantilever will not be subjected to inward force (or even stress) created by off-set arms. What I am interested to know is how much more we can gain from a cartridge when there is no inward force caused by off-set arms.

Perfect tangential alignment aside, there must be benefits from having a "less" stressed cantilever.

I am now almost certain to have a 12inch arm with both off-set and non off-set straight arm wands. Both will be exactly the same except for the head-shell geometry. (So Johnbrown, I do actually listen to other people's opinion.) I will report my findings if there is any interest on this topic.

It really surprised me that I did not get any response from people who have tried or taken this path before. I was really hoping to hear from someone with actual listening experience of a non off-set arms. They have been manufactured before and I am sure there are some still in service out there.

The RSA-1 has somewhat of a cult following for those who do not mind fiddly toys. This arm has no offset and the tangential alignment is way off, but it is acknowledged by some to be a great tracker with very low distortion (soundwise). I will also be getting one of this to see what the buzz is all about.

Don't know if what I am intending to do will be any good, but I am certainly going to enjoy the experience.

Later.

William62  (Threads | Answers | This Thread)


01-07-09: Rauliruegas
Dear William62: +++++ " Don't know if what I am intending to do will be any good, but I am certainly going to enjoy the experience. " +++++

any audio experience is a learning one and certainy could be fun.

Now, why exist a tonearm?, IMHO ( like the TT ) is a tool that the cartridge needs to recovery the information that was/were recorded on each groove on each LP tracks.

Which is de " ideal " way for the cartridge can/could recovery that recorded information?, IMHO that is through a linear tracking tonearm that in theory has no tracking error ( angle ) over the LP.

Well, the main subject/target on that tool name it " tonearm " is to help the cartridge to recover the recorded info with no tracking error ( of course, between other important things ).

IS there other form/way to help to the whole cartridge job different than a linear tracking tonearm?, yes, one of that forms/ways is a pivot/ed tonearm.

will it be any trade-offs using a pivot tonearm against a linear tracking one?, yes, any other tonearm form/design means tracking angle error against cero traking angle error on the linear tracking tonearms.

So, what to do if we want a different/pivot tonearm?, well some people like Baerwald, Loefgren, Stevenson and others made scientific studies to achieve/optimize how to put at minimum that tracking angle error for the cartridge really can to take out the recorded information with almost no ears perception distortions trying to even the linear tracking ( in theory ) cero distortions.

And this was the main subject on those " tonearm projects and was from them that the terms " effective length, overhang and offset " comes out.

Today normally we align the tonearm/cartridge through Baerwald or Loefgren ( where Baerwald has a slightly higher distortion over the LP but the inner grooves against the Loefgren ) trying to have the lowest distortions and the highest quality performance.

Any one of us ( including you, according with what yu posted ) knows that very small deviations on/out that " ideal " alignment alternatives makes a difference in the quality performance and almost always for the worst.

Now, you don't want to make a " small/slightly " change but a " big " one with the non offset tonearm, this fact makes that what you hear will be a far far away " sound " of what is in real in the recording with a lot of distortions, no doubt about because is a totally wrong " road, if you like it or not ( what you are hearing ) it is another matter and does not change the fact that is wrong: you can't change the geometry rules, well at least I think ( with all respect ) you are not a " new " whole geometry proposal scientist man.

If we analize all the different parameters on the tonearm/cartridge alignment/set-up like: VTA/SRA/VTF/overhang/Azymuth/anti-skate/etc, probably the less/least important is the anti-skate and you want to make a " huge/great " trade-off changing the main tonearm target for the " less " important one!!!!!

Have fun.

Regards and enjoy the music.
Raul.

Rauliruegas  (System | Reviews | Threads | Answers | This Thread)


01-07-09: Rauliruegas
Dear William62: I hope that the tonearm designer/dealer already give you the precise indications for the cartridge/tonearm/TT set-up that if you can please share with us.

The other thing that I forgot is that I hope that that tonearm was free of charge to you due that it is certainly useless in a serious way other than " have fun ".

I wish I can/could have the real " perfect " tonearm some day!!, till that " coming " day I have to choose in the better way my trade-offs about.

Regards and enjoy the music.
Raul.

Rauliruegas  (System | Reviews | Threads | Answers | This Thread)


01-08-09: William62
Raul, thank you for taking the time to write. You are a passionate man I could tell. More power to you.

Yes, yes and yes. Alignment is very important - even paramount you would say, but no one has actually touched on:

The inward force that "may" stress the skinny skinny cantilever that is inherent in off-set arms.

Some suggest not using anti skate, but it does not make the inward force go away.

So my big question is:

Will the benefit of a "less stressed" cantilever outweigh a perfectly aligned cartridge that has inward stress imposed on its cantilever?

The cantilever is the weakest part of the arm cartridge system. By eliminating undue stress on the cantilever must be a good thing eh?

I don't know, which is why I am intending to find out. I was also encouraged by the reports from several heavy weights that the RSA-1 which is a non off-set arm - performs flawlessly despite "bad" tangential alignment.

I do not write often these days in vinyl forums as I have found most of what I am looking for in the archives or my personal experience. But on this subject, I have found nothing in any forum.

Like you I am passionate and feel the need to explore, even if it is beyond other people and my comfort zone.

Thanks again Raul. In time I will reveal more madness for us to discuss. You're the man.

Later.


William62  (Threads | Answers | This Thread)



  Post your response
Subject


Your response

No html, but you may use markup tags


Username
Members only

Password