et-2 damping trough-good idea or not?

@rauliruegas

Raul - firstly - what I like to keep in mind for myself. It helps me is this.
All around us are materials that have their own resonant frequency. Now when something is made - with multiple materials, like a tonearm or a cartridge, the resonant frequency becomes that of all the materials, and it depends on what percentages of each material that went into making that tonearm or cartridge. We then join those two - tonearm and cartridge - we get another resonant frequency, and then they interface with something - in this case the vinyl record.

When they are put against a moving vinyl record which is not perfect, and has imperfections I discussed previously - like the ripples; these imperfections, since this is a vibration resonance activity - EXCITE - the resonances. You can see how much in the graph.

That could affects in some way the freely cartridge stylus ridding the recorded LP surface but for forgman " overdamps " with the other wands but aluminum where is an improvement

Look at the graph in my previous post. It describes this scenario. That was a low compliance cartridge set up to produce a lot of resonance with the aluminum armwand. The oil trough smoothed out the resonances. It helped. Now if the carbon fiber or magnesium wand was used instead with the trough, because of these armwands lower frequencies the damping trough would probably have been too much. The results would not have been good and I believe this is what Frogman experienced.
Maybe Frogman can elaborate here if what I am saying is off.

Dear @ct0517  : Through my audio years I learned that well damped tonearms designs always performs and sounds better that non-damped ones.

I remember at least the experiences with 3-4 of my tonearms: Micro Seiki MAX, SME V and Audiocraft where all gives you the posibility to handle damping through silicone oil.

MAX 282: I started to listen it with out the external silicon damping and was just great using any of its 3 diferent arm wands.

One day I put silicon in the tray to look what happens with and what I listened did not like me: suddenly the sound losted " life ", gone in the dark side near severe dull response.
I was disapointed and return to listen with out silicone oil.

In those times I owned too the Audiocraft unit and made the same with similar results, I did not like it with more damping.

Latter on and with more attended events of live music and with experiences seated at near field position I came back to my MAX unit and try again the silicon oil and left that way for 2-3 weeks because after the first week I started to appreciated the true advantages of the damping silicon oil.

Where I listened the first advantage was precisely in the bass range that came tighter, precise, not bloated and with no overhang and this makes that the overall frequency ranges stays truer to what I listened in a live event. The Audiocraft experiences were similar.

Through the time the tonearm damping is a must for me. I own/owned non-damped tonearm as the FR/SAEC and differences for the bad/wrong are truly high vs damped tonearms.

But guess what? several/many audiophiles prefer non-damped tonearms or not very well damped ones.

It's almost imposible to overdamp a tonearm because is extremely dificult to stop/inert the horizontal movements due to LP off-centered, the friction forces generated at the stylus tip and the inner oriented vector generated for th LP spin velocity. Overdamping could means problems with cartridge ridding that we can listen it as a mistracking often events and with my very good damped tonearms the good tracking cartridges even are better trackers and I tested with several LPs like the Telarc 1812 where you can listen with more clarity and precision the cannon shots so the harmonics developed are more open/cleAnsed and this helps A lot to the whole frequency range: bettter overall quality level performance.


The SME uses magnesium build material that's very well self damped material and even that the optional silicon oil external damping always sounds better than with out silicon oil.

The Townshed TT is the more radical example of tonearm damping becuse it happens at the nearest position to the cartridge you can do it and you can hear its very high advantage in the damping regards.

Yes, the damping works diferent with diferent tonearm build materials. Aluminum is more resonant than magnesium so we can hear higher improvements in aluminum than with magnesium but even with magnesium or other less resonant materials always we can listen the damping advantages and its whole benefits.

That we can like the more with out than with is something that I experienced and truly convinced I was way wrong.

I have experiences with other tonearms and results are similar when are well damped and when are non-damped.

For the people, normally, the non-damped are more alive with more detail and better HF but all these alive and the like are only additional generated distortions/resonances/vibrations.

The ET2 designer knows very well what I'm talking about as Townshed too.

In the analog rig our enemy are: resonances/vibrations/generated distortions, so we need the best damping we can in the TT it self, arm board, tonearm, cartridge and the LP surface contact.

I don't know if you remember that Sumiko had on sale a very flexible and low weigth belt-like that was used in helicoidal way around any tonearm wand to function as an additional damping and guess what: it works wonderful !!!!


My advice to the OP is: go a head with the ET2 damping trough.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

At the headshell is the most effective location to apply a damping system to a tonearm/cartridge, for reasons explained in the writings on the design of the Townshend Audio Rock turntables, currently out-of-production. But the Rock is not usable with linear tracking arms, only pivoted ones.

Raul - while acknowledging your experience using damping troughs with pivot arms, you need to recognize that the ET 2.0 and ET 2.5 are unlike any pivot arm, especially when discussing resonances, damping troughs and their effect on Q. They are unique among air bearing linear trackers as well.
Bruce Thigpen has done extensive measurements not just on the ET 2.0 and 2.5 but including many pivot tonearms.

*****************************************

Mass from different wands changes the resonance frequency, but
has very little effect on Q, (the sharpness of a rise in response). A pivoted arm sums the vertical and horizontal resonance frequencies (because of the pivot, they are the same value). The typical rise at the resonant frequency of a pivoted arm will be 12-18dB. Audio Magazine published these figures when they tested tonearms from around 1965 until they ceased publication in 2000.

The ET-2 or 2.5 by comparison splits the resonance into two
different frequencies, one for vertical and one for horizontal, (the
math and discussion are in the tonearm manual) so they do not sum and
the rise is usually about 6-8dB which is much better. This results in a lower wow and flutter figure (about half) when you compare an ET-2 with any pivoted tonearm on the same turntable.

-brucet

*******************************************

So Audio Magazine published these figures when they tested
tonearms from around 1965 until they ceased publication in 2000.
Would you or anyone else reading this - have magazines from that period that show results ?

Anyway Raul, if interested to come up to speed on the ET 2 and 2.5, a good start is with the technical section of the manual. Then I would recommend doing a search on yellow stickies in the ET 2 thread.

The decision for an ET2 owner on whether to use the trough is like having your cake and eating it to. It’s not a this or that scenario, but both. As discussed in this thread already, the oil trough paddle - is a screw design and can be raised to dis-engage and lowered to engage the oil.

It does add 18 gms so putting it on a lightly sprung table like a Linn needs to be considered. 


Cheers Chris

Great explanations from Chris as always.  The only thing that I would add re the issue of “overdamping” is that the best results for me were achieved with the “paddle” just skimming the surface of the fluid.  The paddle can be adjusted up and down and if adjusted so that it sinks too far into the fluid it literally killed transient response.  Not only were high frequencies dulled, but dynamics suffered and the music became lifeless.