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
Last weekend, I picked up a pair of Beovox M70's. First the good news; they are in fantastic shape, and included the original trumpet stands. The wood has very few scratches, the frets look decent - overall, they are in great shape for a pair of speakers that is over 35 years old. Now the bad news; one of the tweeters does not work, so they sound terrible. They also play significantly quieter at the same volume level compared to my pair of S75's (I have them both hooked up to an old, 1980's vintage Onkyo Integra integrated amp).
Where should I start troubleshooting first? Check internal wiring, or old crossovers caps maybe?
One last question - what type of wood did M70's come in? My S75s are rosewood, and these M70's are more of a blond color. Maybe teak that has yellowed with age?
Thanks in advance,
Pete
Not sure about the cross-overs but your tweeter could have a defect. Have just been working on my M70's and I've noticed that the tweeter is (probably) the same as in the P50's or S45-2?. I have a spare one if yours has a defect.
Congrats with your stands!
Brengen & Ophalen
Hi Pete,
Perhaps you've come across my pair here.
I can tell you those speakers are fantastic! They are entirely worth restoring. They are true loudspeakers, they do not add or subdue anything, being very neutral. Some would say they are "mellow" , just utterly musical to my ears and heart.
And they do have great bass too!
The downside is that they are insensitive as speakers go nowadays. But any powerful Beomaster - namely 4400/6000/8000 - will be more than happy to drive them with panache
Jacques
The tweeters in the 2 pairs of M70s I have were the same as the P45 tweeter, different from my S45-2s. The voice coil lead to the terminal is very fragile and will break easily if you rotate that lead just a few degrees. I suspect that may be the cause of your problem. It is fixable.
Hi Rich,
I haven't had the opportunity to look into repairing my m70's. Having small kids takes a lot of free time. Any other repair tips once I finally get the chance to open these up?
Anyway, you had mentioned that you had never seen a pair of trumpet stands after multiple years of searching. There is a pair on ePay now (not mine) although they seem a little expensive. At least there are still a few available.
Thanks for the heads up about the Ebay auction, but one would probably never want to ship M70s for 2 reasons: (1) the phase link magnets are known to slip, and (2) shipping costs are about half the value of the loudspeaker.
To answer your question, if once you have the M70s drivers all working and they sound OK to you, I wouldn't mess with the crossovers. Both of my pairs sounded fine with original crossovers. The pair in my main system have had their crossovers overhauled, but I did that for fun and the experience more than anything else. They still sound fine, of course, but if I had to do it over, I wouldn't have went through the time and expense.
The only thing I would do on the inside is put a bead of epoxy around the magnets of the phase links.
If you are going to mess with the finish, the veneer is very thin. Be careful with your sanding.
Sounds good. I'm glad that you mentioned to not touch the crossovers. I've had a crossover re-cap kits for both my S-45's and S-75's from Martin for nearly a year, and they're still sitting in the bag they were shipped in. One of these days I'll get around to it. At least I epoxied the S-45 woofers, so I should be good there.
Thanks for the note on the thin veneer - luckily the pair I have is in decent shape, and a magic eraser cleaning and a few lemon oil applications made the teak shine.
Thanks for your help! Hopefully I'll get the tweeter running, or source a replacement, if necessary. Any chance you would part with one of your extras? You're much closer to me than Leslie...
Peter Christensen: Any chance you would part with one of your extras? You're much closer to me than Leslie...
Any chance you would part with one of your extras? You're much closer to me than Leslie...
I have one broken spare I've never tried to repair (from a P45), and the other is tied up in R&D (center channel experiments).
Get one from Leslie. He and I have exchanged mail. Mail costs aren't bad and he seems to get his stuff at reasonable prices (supply and demand laws kicking in, I'm sure).