Tonearm recommendation

Dear atmasphere: You was the person that in 2011-2012 posted that we can’t overdamp the TT/platter TT " and from your today post sure we can overdamp if we interfere with its natural movement.

The simple definition of damping is to reduce oscillation. If we use a broader definition as in physics, it would be to reduce or dissipate vibration.  I was making a distinction between different types of vibration control, but it does not matter. Critical damping is just enough to prevent vibration or enough to allow something to return to its rest position.  Overdamping is a state where vibration is prevented to the extent that a moving part is prevented from movement.

A fluid damped tonearm does not have to have the fluid located at the pivot, for the pivot to be damped. Attach a paddle to the base of an armtube and have it dipped in a fluid trough when tracking a record, and you're damping the pivot.  Overdamp the pivot and you're restricting arm movement. 

Sorry Raul, You can't lump all types of vibrations into a pile and deal with them by damping. It doesn't work that way. Damping doe not kill vibrations, it mitigates the affects.  In this case fluid damping an arm pivot can reduce the amplitude of resonance by approx. 50% depending on compliance, mass etc. Damping does not stop the resonance, it redistributes it over a wider frequency range with a less severe peak.

Overdamp the pivot, and as the name implies it's too much, it impedes motion. That's why Stingreen and Crazy Bill experienced negative affects with overdamping. There are other ways to deal with vibration depending on type and situation.

The use of mass is a way to convert vibrations to heat. Consider Mosin's Saskia table. It has a 200 lb. plinth made of slate. Even though slate is good at transmitting vibrations the mass converts them to heat. Another way is to dissipate vibrations and convert to heat or direct them out of the table.  Some coupling should be rigid, not damped. Overdamp everything on a table and the sound turns to mush (opposite of live music).

Regards,

Lewm, Dover, I assume this is the UNI-DIN alignment I read about (Fremer?). Nulls at 66.3 and 112.5mm. If you hunt down the article you'll see the curves for alignment error. It looks pretty good. I'm reluctant to call alignment error, distortion. Unless/until someone correlates alignment error with a master type source and a distortion analyzer, I think the use of the term distortion is misleading. Some people throw this word around who clearly don't know what they're talking about.

I don't have an FR arm and I haven't read the past threads.  It's a little hard to imagine how or why increasing mounting distance 1.5mm would make a significant difference. The only thing I could come up with is a miniscule reduction in offset angle. I believe perception of differences is sometimes fueled by anticipation and expectations, although I'm not saying that is the case here. It could be that Jupiter aligned with Mars and Dertonearm is the 7th son of a 7th son born on a blood moon (whatever that is).  Don't take offense here, I'm a sarcastic type.

It's interesting to note, the factory nulls minimize inner groove problems with that null being close to the run out groove. The outer null is close to Baerwald.  UNI-DIN moves the inner null out near Baerwald, and 112.5 puts the outer null in closer than Loefgren(B). I think this minimizes error in the center of the grooves where error is highest.

Dover, VE has a free protractor called Chpratz. It's just a calibrated straight line. With it, you could experiment with different alignments, although it's not easy to set up like a Dennesen.

Regards,

Raul
If we have not that first new experience then we don’t know if it’s tru or it’s totally wrong. This is the subject here because no one is willing to try it.

I do not like damping on tonearms as a general rule as it tends to suck life out of the sound and at worst smear the sound, particularly spongy or soft materials such as rubber, heat shrink, etc.

I guess my post had as much effect on the argumentative nature of the discussion as a loud burp.

Dover,

*I have also made a metal jig to ensure that the FR64S's that I use are installed with a 231.5mm pivot to spindle distance. It is accurate to 0.1mm and this pivot to stylus distance recommended by Dertonam makes for a considerable audible improvement over the factory recommended 230mm.*

Any further explanation?  Factory alignment nulls are 59.2 and 120.4mm?   Somewhat unusual, inner null is close to Stevenson and outer is close to Baerwald. What alignment do you use?

Regards,

Raul,

Still doesn't make sense:

**What I’m talking is what in a non-existen " perfect audio world " we have in those internal wires: ideally a pure non-contaminated signal information.

I posted that we can’t have it never ever because we have many distortions/noise/vibrations/resonances surrounded the ridding of the cartridge LP grooves modulations as: TT/arm board/Tonearm//air pollution/LP anomalies and that’s why we need to overdamp those audio chain links to be nearer to that " ideally non contaminated pure signal music information ".**

Overdamping is not going to cure the ills from the source.  In fact, overdamping will take you further away from your "ideal signal". Specifically, overdamping a tone arm will negatively effect cartridge transient response - rise/slew.
. Overdamping prevents the arm from responding in a timely manner. Functionally, in some ways it mimics high bearing friction.

I think you call me dogmatic because I won't agree with the nonsense you post.  All the BS about your ear training and you seem incapable of correlating what you hear, with what's going on with the record player.

Listing ID: lis6d99b
My sample is an original one and how can I know it for sure?, because at least three unique characteristics: first its serial number, Dyna numbered from 1 to 99 ( exist other 13 D that are not really 13 D but 17 D that have higher serial number. ) mine is number 6

Inject into the cartridge pure tones that span the audio frequency range, say 20 to 10K Hz at log intervals, e.g., 20, 50, 100, 200, 500, 1K, etc, and at each single frequency, take a look at a spectrum analysis of the output. Absolutely no subjective judgement allowed.

well, any resonance has fundamental frequency where happen that resonance ( it does not matters where it comes. ) and that means that at the same time that is happenuing are created its harmonics exactly as the harmonics in the music and that's why those " distortions " always affect all the listening frequency spectrum and we have to take in count that those " distortions " happen all over the frequency range not only at 8 hz or 20 hz but at 3 khz too ( for whatever reasons. .

And of course we all know that the harmonics of 8Hz (16Hz,24Hz,32Hz,40Hz,48Hz, 56Hz etc) do absolutely no harm to the tonearm in vibration mode whilst the harmonics of 7Hz (14Hz, 21Hz, 28Hz, 35Hz, 42Hz, 49Hz) render the tonearm a weeping sloppy mess..😱

Raul,

Did something upsetting happen in your life? To be honest, your posts seem irrational.  Sometimes when life throws us a curve we react in strange ways. To avoid a negative situation it would be natural to go to something that gives us pleasure, like audio.  

I'm not being condescending, your bit about pure musical information going through the wires is bizarre. Of course you can overdamp an arm. Look at the output on a scope. 

In the past you've made some great contributions to our hobby.  If something else is bothering you now, it might be better worked out with a friend or family.

Regards,

rauliruegas  02-04-2016 4:58am
Dear dover: I must add that that PURE MUSIC SIGNAL that pass through the internal tonearm wires when " touch " the IC cables that send it to the phonopreamp starts the continuos degradation of that true grooves modulations information all over each single link in the system audio chain.

Now, when any kind of distortions " disappear " in that first link ( cartridge/tonearm/TT ) then all the additional single system links distortions are more evident and we have to fine tune each of those system links and sometimes even change some of those links as cables or electronics even we have to adjust our seat position and the speakers position and a check up that the room treatment is not overdamped even to check the SPL we are listening in this totally new experience.
This check up of the SPL we are listening is important because when the distortions goes lower and lower we think that the volume/SPL of what we are hearing goes lower too but it's not really in that way. What's happening is that you are not hearing to the high distortions you were accustom to.

Raul,

*I said " over and over " because almost no one post the right answer explain it why I’m totally wrong or why they are recomended " this or that ". *

Because it doesn't work like that.  You made a case for damping. Damping is one factor, not the main consideration. In the initial post we read that the Jelco arm is inferior. I think you would agree, yet the Jelco is fluid damped at the pivot. Clearly, there are other factors.

You talk about ringing and amplifying vibrations. In my experience with these FR arms, the right headshell combined with a suitable low compliance cartridge, negates this consideration.  I've heard them with a small amount of armtube damping and less than perfect match with cart compliance and still nice results.

Maybe the 4 point would be better, I don't know, but I don't think it falls within the price constraints. This is a matter of opinion not a case of right/wrong. 

Sincerely,

Raul,

I didn't call you stupid.  It was long winded, which I think is accurate. If you object to your nicknames I won't use them.

It might interest you to know that the lower the compliance of a suspension, the lower the amplitude of arm/cart resonance.  We happen to be talking about 2 very low compliance stereo carts.

You previously talked about the metal arm generating resonance and distortion. That's impossible. The arm is not a generator. I assume you meant propagating or amplifying. There are many mistakes like that in your posts. I don't have the time or inclination to correct them.

You've been posting on this forum in English for many years. I've long thought you use language to disguise lack of specific knowledge. If you look over this thread I think you'll see that you are the predominant responder. You say the same thing over and over. We heard you the first time. Why don't you give us a break? 

Sincerely,