DynaVector DV505 is it worth the hassle?

Dear Raul and Genesis, Your remarks and Raul's quote from the DV manual are a bit puzzling to me. How do we reconcile the two concepts of "lightness" as you both mention and tonearm "effective mass"? In their literature DV does make the dual and to me internally contradictory claims for both qualities. In fact, they quote the effective mass (with their standard 15-gram headshell) at 25 grams! (That's high, folks.) As I understand the concept of effective mass, it is a measure of the inertia of the tonearm, which along with the cartridge and hardware mass interacts with the compliance of the cartridge to determine the LF resonant frequency. I don't see how a tonearm can be described as "light" when it has a high effective mass. Mind you, the high effective mass is what you want with a low compliance LOMC, and this is what makes me interested in the DV tonearm, in fact. It certainly is a beautifully made and well thought out product.

Lewm, my post, which is the first response in this thread, mentions the short arm and massiveness of the structure as a whole.

The Dynavector consists of two separate tonearms, a very unusual design allowing for low mass in the vertical plane and high mass in the horizontal plane.

That very short arm (the low mass) is also subject to VTA errors, due to ultra short pivot point. The good news is the high horizontal mass makes for great bass with many cartridges.

It helps to look at a photograph. The Dynavector is such a departure from other designs it's not easy to understand unless you've owned one.

Lewm, pls look up the arm on the Dyna website. The Dyna is 2 arms in one. One for horizontal movement and one for vertical movement. Theoretically, that is what is most desired in a tonearm but has it's own working quirks like Albertporter mentions.

Designing a tonearm like this, you can achieve very high effective mass horizontally and low effective mass vertically. It's hard to explain. You have to see how it works. Idf you see the picture, you can figure it out.

Dear Lewm: Take a look to the 505 manual here:
" 6. Arm resonance in low frequency range " , it is very objective to understand what you ask.

Now, the 505 has a low effective mass ( sub-arm ) against the main arm. It is light, you speak about the 15gr headshell weight but this is the weight not the effective mass that has a direct relationship from at what distance ( from the pivot ) is that weight ( 15grs. ) that in this case that distance is extremely short and this fact gives ( on the vertical way. ) a lower effective mass than the 15gr. weight.

Here it is what you can read on the 507-MK2:

" 2. What is the bi-Axis inertia controlled tonearm.
The tonearm is required to fulfill two functions so that the cartridge can reproduce the exact signal from the record groove. One of these is to hold the cartridge stationary at audible frequencies so that the stylus and cantilever motion is translated into a music system without losses.
The other is to allow the cartridge to track warped records.
These require totally contradictory properties from the tonearm and so all conventional tonearms are a compromise between the two.
However, a very reasonable solution exists in the bi-axis tonearm.
The bi-Axis inertia control tonearm is in effect two arms in one - the main arm beam has an effective-mass that is 3 or 4 times higher compared with conventional tonearm
but moves only horizontally. On the other hand, the sub-arm has a lower effective- mass than any conventional tonearm but moves only in the vertical direction.
This combination means that the high effective-mass in the horizontal direction holds the cartridge steady at audio frequencies, especially at low frequencies and high groove excursions, whilst the low vertical effective-mass allows unmatched warp riding performance. "

Lewm, you can always ask directly to Dynavector whom can/could give you a lot better explanation that I can.

I think that we can give you only what were/are our each one experiences with that tonearm design.

Regards and enjoy the music.
Raul.

I get it. The vertically pivoting portion of the tonearm can develop a relatively high effective mass AND be "light" in weight at the same time, due to its short length. I am especially intrigued by Raul's mention that it can be used with no drilling, by fastening it to the mounting board with double-sided tape.