Which tonearm for vintage Micro Seiki BL-91

Hello
it has been a while... very busy with photography here
So far I have been able to compare on my Micro Seiki BL-91 :
Saec WE-308L (which I restaured myself) with Micro Seiki MA-505 1st version (sold) and Moerch UP-4 (new).
They all received a Miyajima Shilabe as this is my favourite cartridge.
As commented by BPoleti and Br3098 the MA-505 gives more musical sound. The WE-308L outstands in immediacy and punch. The difference is very clear here. For us it is a matter of taste but also it depends on the kind of music. They both sound great. As to the Moerch. It sounds more "normal" nothing special but has good tight and deep bass and is good all rounder but again without drawing the attention to the music. I may say it is very neutral or maybe a bit flat. When we listen to the other two arms our attention goes to the music as if we where at a live performance but each in a different way.
Trying to get my hands on a Lustre GST 801 or a Fidelity research FR64 .
I sold the MA 505 because I had a bad experience with the seller (an ebay seller from Hongkong ) ... and wanted to get rid of the bad experience.
I will decide after trying out the FR and the Lustre if I will buy another MA-505
At this moment the Moerch will go and the SAEC can stay.
Enjoy the music

Tgaral, a caution regarding MA 505 arms.

I picked up a MA 505 from a friend several months ago and noticed the end stub for the counterweight drooped. That is to say it was not in the same plane as the armtube. Looking online I found pictures of other examples which looked similar. A couple of "experts" even stated this was the intended design. But I could easily move the stub up and down and I also found photos of examples which were straight. So I concluded it was damaged and sent it off for repairs. My arm had apparently been dropped since the mounting screws for the stub had been sheared. That repair process was delayed for multiple reasons but I just got word it has now been completed.

The point of my story is to insure any used arm is functioning as designed before evaluating it.

Now regarding your initial question on arm matching your table, it seems to me the critical match is between arm and cartridge. If you have a favored cartridge then I would look to match that with an appropriate arm. Then make certain that arm is positioned correctly (pivot to spindle distance) when mounted. After that it will simply be following the routine alignment procedures.

Pryso
thanks... I know about the drooping end stub. My previous MA-505 had that problem but me too I thought this was normal. A Denon tonearm that came with the turntable had the same problem so I thought it was the design:-)
Now you are telling me, I realize that I sold it as it was and the buyer didn't ask me anything about that. Terribly sorry!!!!

By the way I have seen that you are quite popular here on Audiogon and you are very active here. Can I ask you one more question.
I love my Micro Seiki BL-91. It sounds much better, punchier, dynamic deeper bass and everything than my previous BL-51 ( with a fixed static balanced tonearm that was sold as a set here in Japan during its commercialization years).
I have been reading posts about "plinthless" versus "plinthed" turntables. Lots of new desings like Clearaudio still have both in their catalogue.
Can I assume that this is a matter of taste? I remember another very popular member "Raul" saying that he has changed his mind about Micro Seiki and plinths. Or is as you stated the combination of the tonearm and the cartridge more important once you have the plinth isolated. and the vibration reduced as well as one can or thinks he can.
I cannot compare, very simply because I don't have the money for new high-end turntables. That is why I ask you ....experienced audiophiles.
Thanks a lot
enjoy the music

Well Tgaral, I might question your judgement in calling me "popular" here on Audiogon. Many others have greater knowledge and post more than I do.

Regarding your BL-91, I can't comment. I don't know if I've ever even seen one.

Regarding plinthed VS plinthless, I've read enough opinions on that to know there is nothing close to any consensus. I suspect it relates to the amount of energy (possible micro vibrations) generated by a given motor unit design. The one point I feel strongly about is maintaining an absolutely stable relationship between the platter and the arm/cartridge/stylus. Why would the cartridge/stylus set up be so critical if that stability was not important?

So my only advice in your case would be to study all the Micro Seiki table designs. Which of their higher end models have the most similar drive system to your BL-91? I believe from their reputation the MS designers had a pretty good idea what they were doing so copying that to the extent possible may be helpful. Good luck.

Thank you Pryso, and all of you who have been sharing their experience and knowledge. I guess the only way is trying and spending money ;-)
More opinions welcome of course