String suspension vs. uni pivot or gimball tonearms

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I think that string suspension tonearm allows the whole arm to oscillate back and forth to follow the music passage on the record which results the relaxed/natural sound characterisctics. Even the movements only in fractions of a millimeter, it's still back and forth movements. Pivot supported tonearms do not allow the back and forth movements hence more accurate/restricted musical reproduction.
When the string supported tonearm moves forward to comply with the heavy music passage, the stylus remains on that section of the groove a fractional of a second longer than a pivot tonearm would. This time delay creates longer sustainment of the music note. The string supported tonearms also provide more freedom for the arm to track the groove which results more natural music. Some string suspended arm employs damping materials to create more accurate sense musical image.
 
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I aligned a string suspended arm a little while ago, and wondered where the pivot actually was - so was I wasting my time? The arm had a huge amount of viscous damping, so it took a good deal of time for it to settle. It eventually settled, and I did decide that I had probably aligned the arm and that gentle manipulation probably wouldn't disturb the pivot point.

The moment you accept that an arm pivot can move backwards or forwards, you have also accepted wow (flutter isn't possible because of the mass).

I think that if you are looking for a reason why string suspended arms sound good, you should look at rattling bearings in more conventional arms. As it is, your argument identifies one of a string suspended arm's problems.
 
The string suspended tonearm does not have a fixed pivot per se but the arm movements were so small so tracking alignment was not affect too much. The extra freedom from variable pivot centers allow the arm to track the groove more gently. The pivoted tonearm forces the arm only move horizontal and vertical fashions. These restrictive movements force the arm digging into the groove more aggressively if mis aligned. Since I started using string suspension tonearm, I rarely heard inner groove distortions. I think the string suspension tonearm actually causes lesser record wear due to the give and take nature of the arm.
 
SY said:
That would cause pitch wander, too, wouldn't it?

Yes, but how much is it? A well trained ear can hear a difference of 2 centi tones under well controlled conditions and with a direct A-B comparison. That is aprox. 0.1 %. If the wander is well damped how much will speed modulation caused by the wander be?

Cheers ;)
 
Well, that will depend upon the compliance of the pivot point, the relative friction between a loud passage and a quiet one, and the frequency in question. Pitch acuity is indeed germane, but there are other mechanisms, too- one may not be able to point to the pitch changes as such, but as when going from a turntable with moderate wow to one with fabulously low wow, the subjective "solidity" may be audible.
 
"Be that a good wow or a bad wow." I think it's a good wow. Under stable condition the tiny wow may be perceived as a natural decay of a string instrument like guitar. More wow it seems like the guitar string got stretched for special effects. I hardly noticed the wow on vocals. The gimball tonearm does not have this kind of wow because the bearing movements just dissipate the decaying sonic energy faster. String support tonearm is like a string instrument. The string vibration is similar to the vibrating stylus. The body of the instrument is the arm wand. The string suspension of the arm is the string of the string instrument. That is why wooden arm wand string support tonearm sounds more natural than metal arm wand.
Has anyone ever install a wooden armwand on the Well Tempered tonearm? Just make sure the wooden arm wand has the same weight as the original arm wand for stability and effective mass.
 
nghiep said:
"Be that a good wow or a bad wow." I think it's a good wow. Under stable condition the tiny wow may be perceived as a natural decay of a string instrument like guitar.

Hi nghiep,

Second that, the effect of the pitch shift due to the drag is more in coincidence with the nature of the music. A bit in a way as 2nd harmonic distortion vs 3rd harmonic distortion.

But I don’t agree that the string acts in a similar way as a string instrument.. For a tone arm the string suspension should be well damped so the arm mass with the spring action of the suspension does not oscillate. Quite the contrary of what is needed for string instruments. And this damping is done in the Well Tempered as well as in the Schroder arms.

Cheers
 
Ok, now heres a thought..
String suspension arms can use 1 magnet to stabilise the point of rotation, or two.

If using 2 then you lose the inherent self damping characteristics by eddy induction in the screw/washer being used in the 1 magnet system... but the benefit is a much tighter coupling between wand and base

In the single magnet system, the screw/washer being used as a damping device will actively decay the 'wow' very rapidly (an overdamped scenario)...

In sound terms I would expect the latter to be relaxed, and 'spacious', whilst the former would be 'pacey', tight and precise...

And the length of the string will also play a vital role in the overall sound.

Just some grits...


Owen
 
This is my thinking about pivoted versus string suspended arm: (I planned during my vacancy in Denmark last summer a string suspended arm, because my self made (cardanic) arm has to be re-designed due to resonances)

In a pivoted arm: (and this arm has usually a metal arm-tube also) the resonances of the cartidge is conducting right into the base the arm, this is a "hard" connection to its base, with "metal" sounding (and unnatural) harmonics. The ball, sapphire or unipivot bearing is a hard connection, with the metal armtube.

String suspended arm, and then preferably with a carbon or wooden arm-material has the advantage of a dampening connection to the pivot, and the pivot itself also dampens the resonances. When the string is under the right tension, almost all resonances could be dampened imo.

Its like a rope tight on a metal ring screwed on a wall, swing the rope, the hard connection on the wall reflects the wave back into the rope. Even second and maybe third harmonics can be made. Mount the rope via an elastic band to the ring on the wall: now its more difficult to keep a nice swing in the rope, and higher harmonics are more difficult.

Only thougts yet, first i will change my metal arm tube to a woven carbon tube.
 
Hi Tubee,

Agree with that. In fact the cantilever is “grounded” by the mass of the cartridge and head shell. This forms a high pass filter above the compliance/effective mass resonance. The only thing what is needed further is keep the stylus in place on the moving record surface. There is no need at all to drain vibrations into the base.

Obviously there are some vibrations transmitted from the cantilever into the arm that will travel further there and excite some parasitic resonates of the arm which eventually reflect back into the cartridge. So what is needed is to dampen this debris sufficiently, not to drain it into the base.

Have seen on the internet a construction where the cart was mounted in the head shell by means of a sheet of damping rubber to block vibrations going into the arm.

Cheers ;)
 
Have seen on the internet a construction where the cart was mounted in the head shell by means of a sheet of damping rubber to block vibrations going into the arm.

Hello Pjotr.

This i did allready also 1/2 year ago, to get rid of resonances. Now my cart is suspended in foamy rubber, and the base of the arm i have decoupled also with rubber rings under the bolts.
With an sthetoscope is now less mid-range rubbish heard in the base of TT. Soundimage is more sharp now, but bass slightly less tight
 
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