Ortofon MC A90 Cartridge VTF


I just spent the weekend at mikelavigne's where we did a comparison with three turntables all using the same Ortofon MC A90 cartridges. We had the cartridges setup at the recommended VTF and they did not all have the same amount of break-in time on them. I decided to see what would happen when we lightened the cartridges up.

We started on the first table and the weight was about 2.25. We lessened the weight until I thought that the sound really locked in. By the time we were done on the first turntable, the VTF was at around 1.56. When we did the second table we got the weight all the way down to 1.92. On the third table it ended up best at about 2.01.

All parties (myself, Mike and Steve) agreed that lightening up the carts really opened things up quite a bit without loss of bass. The inner detail and delicacy inreased as did speed and dynamics.

I called Ortofon and am awaiting a response but I was wondering if those of you who own this cartridge have gone outside the recommended range and if you could share your experiences.

There is more to read about this if you want under mikelavigne's system thread.
jtinn
Mikelavigne, it sounds like for this cartridge, the Reed has the optimum resonance frequency. I will soon be getting a Bergman tt and will be able to see where I need to see how low a tracking force I can use as well as what VTA is optimal.

In some respects the "everything fixed" approach of Shindo was a good deal easier, but allowed little experimentation. One had to accept Ken Shindo's judgment.
Dear Mikelavigne: All those differences in VTF seems to me that explain the intimate relationship between cartridge/tonearm/TT that are different in each set up, what is a " surprise " to me is that down/below the VTF manufacturer range the cartridge still performs on " target " with centered coils. Probably at that VTF set up are still centered.

Btw, what happen with the Jtinn question on the subject to Ortofon? has he already an answer?

Regards and enjoy the music,
Raul.
Raul, yes jtinn did get a reply (which he read to me) from Ortofon, which he told me he will be posting 'soon'.
Thanks Steve. Your comment was very informative and helpful. I have an A90 and will give it a try soon. I'll keep this in mind. My guess from what you mentioned is that I'll probably be on the higher end of the vtf spectrum.

Andrew
Another good question Norm. 2.25 g was the optimal sound to my ears with the Tri-Planar. I went as low as 2.10 but the sound lost a lot of the fullness or weight it had at 2.25. It will be interesting to see how low I can go on VTF before the A90 mistracks on the Tri-Planar. I will do that this weekend and post the results.