Tgaral, please don't misunderstand my previous comments. The BL-91 is a great deck. But turntable technology (or our perception of such) has changed a bit since the late 1970s. The BL-91 is constructed of veneered plywood. This was quite good in the late 1970s, and was considered to be non-resonant. Improvements in materials and construction techniques have led to significant changes in plinth technology over the last 25 years or so.
Remember, the original (standard) tonearm for this deck was the MA-707, which is rather low mass unit. I believe that the MA-505 will provide a much better sonic result withour breaking the bank. Can you do better? Probably, but what is it worth for the small additional gain? (this, of course, being the original audiophile conundrum)
If I read your last note correctly, you are being offered an MA-505 for $300? If this is a "real" MA-505 (and not a re-purposed DD-40 variant) this is a very good price. Is it a MkI or II (S-shaped) or a MkIII (straight) model?
Regarding your questions about additional damping for the BL-91, frankly I wouldn't bother. You might make some minor improvements but in doing so you may jeopardize the resale value of the unit. Unless you hear a problem when played, I would just leave it alone and enjoy it for what it is: a very nice vintage turntable.
Remember, the original (standard) tonearm for this deck was the MA-707, which is rather low mass unit. I believe that the MA-505 will provide a much better sonic result withour breaking the bank. Can you do better? Probably, but what is it worth for the small additional gain? (this, of course, being the original audiophile conundrum)
If I read your last note correctly, you are being offered an MA-505 for $300? If this is a "real" MA-505 (and not a re-purposed DD-40 variant) this is a very good price. Is it a MkI or II (S-shaped) or a MkIII (straight) model?
Regarding your questions about additional damping for the BL-91, frankly I wouldn't bother. You might make some minor improvements but in doing so you may jeopardize the resale value of the unit. Unless you hear a problem when played, I would just leave it alone and enjoy it for what it is: a very nice vintage turntable.