Micro Acoustics FRM-3

Hanleyster

ambitious but rubbish
Found these at SA today for $10. Did I do good? I cant really find any info on them. I was afraid they were junk, but took the risk.
 

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Micro Acoustics version of the Bose 301. MA wanted to design their MA phono cartridges and made speakers to fund the design work for their cartridges. They were considered better than the 301's in their day.
 
Certainly not junk, but not spectacular either. They date from the mid '70s; the 3s were the smallest of the line at $99 (not sure if that's a pair or single). The FRM-1 had five tweeters, the -2 had three as did your -3. They also made an add-on "microstatic" tweeter array to add to an existing speaker.

As said, Micro Acoustics' big deal was their cartridges, which still hold their own today.

Happy trails,
Larry B.
 
You can adjust the angle of the "lollipop tweeter" with a knob on the outside.

I think these are going to be out of my league to restore, might pass them off to an expert friend of mine. I assume they need caps, and the foams are in need of replacement.
 

You gotta love it; Bose being Bose. They hold the dubious distinction of being the only company ever to sue its own trade group (CEDIA) for infringing on a "trademarked" phrase (they lost, big time).

Notwithstanding any merits or demerits of their products, I find Bose's constant appetite for litigation to be reprehensible.

Heck, I'd keep those Micro Acoustics just because they withstood the Bose onslaught!

Happy trails
Larry B.
 
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FRM-3's

Those little speakers are better than you might think!

I had used a set of AR-18's through high school and had to sell my system. Later, going to college I needed a new system...in 1982 Circuit City had a small store in Knoxville so I went there.

Having owned the AR's with a Kenwood KA-3500 I knew what a good, inexpensive system could sound like. The salesman had a Technics floor model receiver, so I chose it. Then for speakers. They were trying HARD to sell Interaudio speakers. As I recall, they were a cheap Bose-made speaker. I was open to anything my ears liked but they hated the speakers. They had a set on clearance they brought out. They were Micro-Acoustics. I knew the quality of MA phono carts so I listened. A/B'ing the speakers I could afford showed the MA's to be best by far. The high end was smooth, almost subdued. I liked them with a bit of treble boost. The bottom was an 8", ported. Bass was ample and controlled for a small speaker. The "lollipop" tweeter had a fuse on it that glowed in use! It was covered in cardboard to cover the light...the build quality was as good or better than my AR's. Solid cabinets with lots of weight to them and good padding inside.

After college they served as my main speakers for years. I eventually put them in my parents bedroom as front speakers in their first home theater set-up. The surrounds finally gave way despite the use of anti-fungal creme on the foam (it was worth a try!) and they gave-out in 1998. I cannot believe I didn't keep them but I was ignorant of woofer reforming, then.

The high-end rolls-off quickly but still they have a decent soundstage. The tweeter adjustment is simply a way to direct tweeter output for L/R or up?down adjustment. No intention to use these as "reflecting" speakers was ever made. An experiment trying them that way taught me to use them normally. In "reflecting" mode they would have needed another tweeter! Bose went after them without merit but the fight made selling the FRM-3 an expensive proposition.

A nice small speaker. $99.00 each sounds about right for the time.
 
Cool thanks for the reply! I still havent gotten around to replacing the foam.

The front panel is 1" thick, they could hold up to a modern car audio subwoofer!

I wonder where I would get the surround foam??
 
I have a pair of FRM-3'. I reformed the woofers and they sound decent. I think the tweeters have both been replaced some time ago. My question is does anyone know if the original tweeters were 8ohm or 4ohm? Mine currently have 4 ohm with 3.8uf caps if I remember correctly. That seems pretty low for a 4ohm tweeter. The only info I can says the crossover point is 2500hz
 
I too have a pair of these that I picked up for free. Mine do not have grills though. I was under the impression that the original grills were thick open cell foam like some of the JBL grills. It looks like your grills have a wood frame?? Would you be willing to take a few more pictures of the grills from the back?

Here are mine: http://audiokarma.org/forums/showthread.php?t=305992
 
Mine don't have any grills either. I had a friend that had a pair of these back in the 70's and they just had thick foam grills. I don't even think they had frames behind the foam. I am going to just make wood frames and use grill cloth on mine.
Do you happen to know if yours has 8ohm or 4ohm tweeters?
 
Mine don't have any grills either. I had a friend that had a pair of these back in the 70's and they just had thick foam grills. I don't even think they had frames behind the foam. I am going to just make wood frames and use grill cloth on mine.
Do you happen to know if yours has 8ohm or 4ohm tweeters?

Not sure.... I will try to check over the weekend but they are currently buried under a pile of gear:D
 
Thanks! There doesn't seem to be a lot of these speakers around anymore.
Once I get mine in good order I'll dig out a set of Bose 301's and compare them. I suspect the MA's will sound better. The cabinet is bigger and a lot stiffer.

Did you refoam yours yet? Looks like they are in pretty good condition.
 
I had a pair which had been refoamed by a previous owner using circles of red velvet(!). Nonetheless, they sounded good -- bigger than they actually were, and smooth.
I was surprised because the bigger MAs I had heard in college were very bright and perhaps deficient in the mids. In retrospect, grainy 70s transistor amps may have had something to do with it because I've heard them sounding very good with better electronics since then.
 
I played mine a lot yesterday. They sound pretty good considering they have 2 different tweeters in them. One is alnico the other looks pretty modern I don't believe either is original. I plan on replacing both and possibly using a better crossover rather than just a cap for the tweeter.
 
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