Beovox MC120.2 part restoration - was it worth it?

Almost a year ago, I bought a pair of Beovox MC120.2 speakers on eBay.Fr.  They arrived in a very thin cardboard box with a sheet of wallpaper as packing material.  You can all guess how they arrived.  They were completely trashed externally - all cabinet corners were broken, they were covered in dents, chips and scratches, nearly all of the 3 pronged grill pegs had sheared off, the grill metal frames were bent, the black plastic bass port grills were smashed/bent and the bass driver foams were fairly shredded!  No surprise really.

Never having experienced these speakers before, I left them stored and claimed against the seller - who was actually really good (possibly scamming the Post Office insurance) but I got a full refund and kept the speakers.  I ordered new driver foams in case I ever got around to doing anything with them - e.g. plucked up the courage to tackle them.

That time came a few days ago.  In my haste to work on these, I unfortunately didn't take 'before' pictures (some will say therefore, it never happened')  My family will attest to the state they were in.

For those who don't know these speakers - they are a doddle to open up and a great design to work on. There are 6 cross headed screws holding the front on (with 2 blank holes in the middle for the speaker grill pegs).  Unscrew those screws - 2 were really bent!  Then, work the front loose and lift the whole front off while the cabinets are lying on their back.  

All that is now connecting the speakers to the cabinet are the two cables from the speaker connectors at the rear of the cabinet.  They are on spade connectors so just pull them off and either take a photo or mark in pencil where the grey and brown wires attach.

I've removed them already but you can see the two spade connectors.

I unscrewed the crossover as on one of them (above), the bottom magnet of one coil had sheared in two and the coil was just flopping around.  Taking a chance, I reglued it with JB Weld which is a metal based two part epoxy and clamped it.  It was a clean break and the two pieces matched exactly.  The next day it was as solid as a normal piece of metal.  I used hot melt glue to re-attach the coil to the board, top and bottom.  The corner of the board itself had also snapped off where one of the mounting screws goes and was re-attached with the JB Weld.  It sets hard as rock but can still be drilled, filed, sanded etc.

All capacitors looked fresh with no sign of leaks or bulges  so I've left them as is for now.  I'm not sure if these speakers have had much use before.  Keep hold of that piece of foam, it will need to go back later.

Remove the +ve and -ve leads from the speaker which again are spade connectors and colour coded. Turn the speakers over and remove the four metal retainers and rubber blocks.

The driver is held with a rubber ring/gasket onto a plastic surround.  You can gently just prise these apart.  Wash the plastic and clean the rubber with some IPA.  

Then the fun job of removing the old foam is the next thing to do.

From around the top of the spider, the rubber can be rubbed off with thumb and finger as the glue tends to 'roll' into a ball.  Residue can be removed with acetone.  From around the speaker cone, I removed as much as possible by hand, then moistened the residue with acetone and wiped of the rest.  The cone does not react with acetone.

Some of the remnants and numerous cotton buds used for one driver:

Now, subject to rebuke/comments from you all, I treated the two drivers differently as a test - I was a research scientist after all before I retired.  I refoamed one without shimming and the second, I did shim with some thin acetate film.  The dust cap was horrible to cut open so I'm glad I didn't do the other one.

There were more pieces (4 in total) of acetate when it was all glued.

I cleaned out and reglued (hot melt glue again) the inside of the cabinets, the stand retaining pieces on the back and around the speaker connection housings which were all loose.

The exteriors of the cabinets were filled or rebuilt in the corners with wood filler (either cherry or mahoganay - SintoBois filler), then coloured with Liberon 3 part touch up pen (mahoganay again) and also a self made mix of Liberon water based wood dyes  using the brown, orange and red until I got a close colour to the Rosewood.  I also used a black permanent marker for the darker sections.  All sanded with a very fine, damp  sanding sponge.  Wiped off with water and then alcohol.  Allowed to dry and then treated with Liberon Superior Danish Oil.

This is just before the Danish Oil went on:

And after:

Interior foam was returned, plastic fronts of the speakers cleaned with Car interior Plastic cleaner and all re-connected and re-assembled after straightening the screws and putting that foam piece back.

I'm going to try to repair the black bass port baffles by heating them with a heat gun and bending them back into shape.  I'll report back on that method later.

Here is the result so far.  The top left corner of one is as good as I can get it without stripping veneer and redoing the whole thing.  I wanted to avoid doing that as each coresponding face of each cabinet is cut from successive pieces of veneer and is an exact match - they are in effect identical twins.

Last week they were ready for the skip so I'm quite please with how they look.  They will improve when I get the grills finished and the baffles back.

The moment of truth was when I connected them to a BC9500 that is also externally trashed but fully functions!  Using the AUX with my iPad, I was actually completely bowled over with how these sound. The detail and clarity is astounding.  I heard things on some live tracks that I have played for years and heard new things.  Volume is no issue either.  I got shouted at for playing them too loud.  No hiss or crackle, only complete silence between tracks.  No distortion at all, even at high volumes and over all frequencies to date.  I can't detect any difference between the shimmed and unshimmed refoamed driver. 

I'm gently 'running them in' now - ready for my step-daughter using this set-up for a summer party in a few weeks. She's sensible otherwise she'd have no chance.

So, was it worth it?  Absolutely.  I'd recommend these MC120.2 speakers to anybody.  They sound georgous.

As an aside, I also fixed a non-working Beolit 500 today.  So simple - the spring loaded battery terminal was binding rather than sliding towards the battery tube so wasn't making contact.  Cleaned it up and put a bit of fader lube on it and for the first time in 5 years I have lovely music from a nice old radio.  I only got it out to measure the antenna tip for Soren!  Thanks Soren.

Dave.

Very nice job on the restoration. Were the grill covers pretty beat up?  Do you have the stands for them?

-John

Hi Dave!

A tremendous job indeed Dave, and a first for you on Beoworld, if memory serves.

I know the Perspective MC120-2 well, having a pair myself, bought 4 years ago in Germany. They are room-dependent though, but I can confirm that when located in the proper room, they indeed sound lovely.

In my upstairs room - 40 square meters and very high ceiling - they sounded dull with no bass to speak of.

In my downstairs room, with French oak ceiling, they sound absolutely lovely, which fits your description perfectly.

These are often described as one of the best passive speakers that B&O produced. Fancy a pair of MS150 Dave?

Have you got the stands by the way?

Hi Jacques. Yes, of course. I'm hoping to get to visit Martin later this year as he Has a pair of speakers set aside for me but I can't remember what they are! I'll follow this up soon on the plastic grill work. They are quite mangled but I'm hopeful some heat will allow me to 'mould' them back into shape.

Dave.

Dave,

Brilliant work indeed. I have heard many good things about these speakers, I really must find a pair! Keep us posted with the grill work!

Ben

Very nice result! Next time, you open your 'boxes', I can recommend you to try theese four jobs for futher improvement of this brilliant speaker: 1. Shortcutting overload circuit (thermofuse + diodelamp) 2. Replacing the black foam ind the woofermagnet (risk of rot) 3. Replacing capacitors in signalway with tweeter and midtone 4. Put to extra screws into the vacant holes in the frontbaffle, which is very heavy.

Best regards

Bjarne