Beovox MS150 speakers slowly coming together...

Jon — Sat, 11 Apr 2009 01:31:52 GMT

Hey all, I wasn't sure whether to put this in the General Forum, or here, so I chose here, since this is restoration work - I had been putting my posts in the General Forum before. I've been fixing my MS150 speakers, and here’s some pictures of what little progress I’ve made. Hope you guys get a kick out of ‘em.

I finally got the mid-bass drivers, and then re-foamed them and cleaned them up cosmetically just a tad. Seems like they’re in nice shape overall.

Here’s the motor of the driver. It’s nice and hefty for an 8” I think. I like the copper sleeve through the pole piece. It’s got a 3” VC, and a flat cone profile – alot like a Dyn driver, but I really don’t know who the OEM was. I’d love to see how these measure; the motor is really nice, but it’s got a smallish spider, and it’s not vented either. It‘s high passed at 150Hz though, so I don’t think it’ll be moving too much. The whole driver is supposed to be loaded into a cardboard tube inside the enclosure, so I’ll have to figure that out, as whoever re-foamed the old drivers tossed them. Not sure if I want to use a tube shape – I was thinking more of a cone for the reflections, although the internal volume will be less.

I’m almost ready to put these speakers back together, I just have to fix this:

It broke part of the copper trace from the PC board. I’m sure these electrolytic caps have drifted far from their original values after almost 30 years, so eventually, I’m going to build new crossovers, although the protection circuit might pose a challenge. I may mount it all externally from the speaker in a black box on my TV stand.

I’m getting closer! Can’t wait to hear them.

Jon

The Workbench

Beovox MS150 speakers slowly coming together...