ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Greetings all -
Over the weekend I had the opportunity to pick up a pair of Rosewood S75 speakers to use with my Beomaster 4400. Sadly once I got them home and setup I found that one of the speakers is having issues with the mid drivers and potentially the tweeter. The woofer is the only thing I am sure of that is working.
I spent some time researching next-steps here on the forum but wanted to get a bit more detailed answers before moving forward. I understand that I want to test the individual drivers and that the best way to do this is with an electric meter to check the ohm levels. However I'm not sure what the different drivers should be seeing in that regard. Also....should I hook the individual drivers up to an amp to see if they work like that? Do a battery check? (I wouldn't use the 4400 for this type of work :-) )
Moving off the drivers to the crossovers...I have a feeling the capacitors may need some touching up - in fact I believe that is going to be the crux of my problem. Would the recommendation be to do both speakers at the same time to best match sound quality? Are there capacitors that are favored for these speakers or should 'any' quatity piece work?
Finally...is there anything else I should do with these guys while they're under repair? I'd like to get everything done initially. Anyone have a favorite way to clean or even lightly refinish them? One looks about perfect while the other looks like it's warped slightly. Cosmetically only...
Thanks!
- Paul
Battery check is fine for the cone drivers but possibly not so useful for the domes. I would initially suspect the cross over - the scematics are I think on site and it is a question of testing each component.
Almost all drivers are better repaired than replaced as finding an exact match will be nigh impossible.
Finishing the cabinet is just a question of elbow grease! Remove the existing finish with wirewool and linseed oil/white spirit. Then either Danish oil or beeswax - whichever you prefer.
Peter
Crossovers: change caps, Check each component (coils, resistors), bipolar caps are available from web shops or buy from Dillen on this forum, comes with instructions.
Check cables and connections from crossovers to drivers.
Cabinets: Clean with IPA, sand with 200 grain until wood is clean and even color, clean, sand with 4000 grain, clean off all dust, (use lint free moist rag), soak with boiled linseed oil, after 1/2 an hour wipe off excess, leave over night, sand light with 400 grain, oil, 1/2 hour, wipe off excess, leave over night, polish with lint free rag.
Danish oil is basically boiled linseed oil.
Collecting Vintage B&O is not a hobby, its a lifestyle.
My advice: whatever you do, take photographs of each step and post your progress here. Members will chime in regularly with advice and words of encouragement.
Inspiration for you.