Discuss The Viv Lab Rigid Arm

Dear @rsf507  : I could think that you already know that the recording/playback overall process is full of imperfections and trade-offs.

Could you share which is your target doing that question? or maybe you already have the answer.

R.

@rauliruegas I thought it was a simple question. Since I’ve never used or seen a ViV arm and in the review Mr Gregory said it was difficult to get an accurate repeatable VTF, the question was aimed at those with direct experience, is getting repeatable and accurate VTF with this arm?

rsf, In my opinion, the pivot point should be fixed in space.  I do not view Roy Gregory's report that you cite as a good thing.

Dover, I have to think about this some more, but off the top of my head, I do not think it is possible to set up an underhung tonearm so as to achieve two null points on the surface of an LP, no matter what you do with the headshell offset angle.  Also, I disagree with the Viv website, if they say that the combination of zero headshell offset angle and underhung-ness has the net effect per se of reducing the skating force.  What it does do is create a smoother more linear transition in the magnitude of the skating force as the stylus traverses the LP surface.  Maybe this factor makes the high TAE at extremes of travel more benign than it would be in a conventional pivoted tonearm.  Just guessing.

lewm

I do not think it is possible to set up an underhung tonearm so as to achieve two null points on the surface of an LP, no matter what you do with the headshell offset angle.

I think you are correct. That's the whole raison d'être for overhang and offset, no?

@lewm 

Dover, I have to think about this some more, but off the top of my head, I do not think it is possible to set up an underhung tonearm so as to achieve two null points on the surface of an LP, no matter what you do with the headshell offset angle. 

You have misconstrued what I am suggesting.

I am suggesting keeping the headshell offset at 0 ( straight ) move the arm mounting point forward in order to set 2 null points. The 2 null points could be anything, for example 1/3 & 2/3 across the record. The 7 inch arm is probably not possible, but certainly the longer ones could be set up this way.

My gut feel is that the straight headshell has more impact than the "underhung" geometry.

With the "underhung" claimed by VIV I don't get it. If you look at their set up template their null point is in the middle of the record playing area, which means that irrespective of the "underhung" set up, skating forces are going positive and negative as the cartridge tracks across the record.

If they set the null at the end of the record, then the skating forces would always be in 1 direction only, and therefore much easier to control.