I have a pair of MC120.2's too and find them wonderful speakers. Obviously the incorrect woofers will be doing you no favours. Either refoam the originals (not too difficult) or you can buy new peerless drivers for them (800667 or something similar - have a search on here for the correct peerless number). I would recommend changing the capacitors in the cross over as that will make a difference too.

When working well they are superb speakers.

That was what i thought too, my plan is to refoam the originals. Do you know where i can find such a set for re-foaming and the capacitors i need? Looking forward to test them!

Even if the foam are rotten on the original drivers, and even if i try other 8-inch drivers in the speakers, there should be some amount of bass. I wonder if the crossovers are faulty. Anyone who has experienced something like this on similar speakers and solved it with a change of capacitors?

johansens wrote:

Even if the foam are rotten on the original drivers, and even if i try other 8-inch drivers in the speakers, there should be some amount of bass. I wonder if the crossovers are faulty. Anyone who has experienced something like this on similar speakers and solved it with a change of capacitors?

Caps won't do that much either way for bass, since they are mostly involved in the mid and treble networks. However, there's a remote possibility that both of the crossovers have a blown coil or resistor. Do the bass drivers move at all, this should be obvious to see/feel even at low volume?

Ok. The bass drivers do move, and it increases with the volume. Problem is that mid/treble are very dominant compared to the bass. Both type of bassdrivers are acting the same way. I have to set bass-settings to max on all the different amp's i've tried, just to aquire a somewhat balanced output from the 3 drivers. Mid/treble seems to be working well. From what i have read on this forum, these speakers should be more than powerful enough in the bass-range.

The service manual is sadly lacking from the site (or I just cannot find it), so I don't know how the crossover looks like. However, I guess you could just take a look at them; if there are burnt resistors, those should be pretty obvious.

There is also the possibility that the "new" drivers are totally unsuitable for the job and therefore sound weak. And if the surrounds have rotted through on the original ones, they will not sound good either, as the bass frequencies will just short circuit round the cone as if they weren't installed in an enclosure at all (and you may damage the voice coils trying to play them too loud).

In short, you can't really say much about the speakers with incorrect or broken drivers!

tournedos wrote:

In short, you can't really say much about the speakers with incorrect or broken drivers!

Absolutely!

Refoam the originals and put them back in.

Also, take a look over here.

P.S. Welcome to BeoWorld!

The service manual for the S120 is on site - look under the MS150. I don't think I have the MC120.2 and don't know the changes.

Oh yes, I suppose those would be quite similar. In S120, there's only one coil in series with the woofer (and an RC network in parallel, but a fault in there would probably only make the bass louder). So if that coil had burned, there would be no signal at all to the bass driver.

So - if the overload protector has been reset (pressed in) and it is not oxidized - there can't really be much else of a problem than the drivers themselves. And I stress that if the originals have a lot of holes in the surrounds, they simply cannot create much sound pressure at low frequencies!