YAMAHA NS-1000M drivers cleaning and rufurbishment

[Cosmin2000]

Hello, audiophile friends! I recently acquired a pair of these well known monitors.
They sound good, but from the aesthetic considerations they are way behind my expectations:scratch2:. Therefore, I decided to clean the drivers and refurbish the enclosures. Also, the protective case for the mid-range drivers are bent/dented. Moreover, one mid-dome has some stains, the other one is in a better shape.
I would like to ask if the cleaning of the beryllium domes is a good idea? If yes, what is recommended for this operation (tools, wipes, some special cleaning agent etc.)?
Have anyone done this? Thanks in advance!

 

[Cosmin2000]

The enclosures will be refurbished. At this moment, the old black veneer is removed and a new one is expected to be applied in a couple of days (see attached photos).
I gave the two enclosures to a good friend of mine which works in the wood/furniture business. So, in this respect I'm confident he will make a good job on these babies. I'm very keen to see the end result.

 

[SteveS in VA]

Interesting. Black veneer was applied over WALNUT. The walnut veneer is pretty well trashed on the top corners--that's too bad. Repair would be possible, but it would take a master to get those corners right with a clear finish.

 

[Cosmin2000]

I do not worry about these defects of the raw walnut veneer. I have the right person to tackle this tedious job. My concerns are related to the beryllium drivers cleaning operation. Any advice, opinion?

 

[donprice]

Beryllium is quite toxic and and you shouldn't mess with it unless you have a very good understanding of what you are getting into.

Cleaning the non-beryllium parts is another matter. Unfortunately I have zero experience with these drivers and have nothing to offer.

 

[Cosmin2000]

Thanks for your post, donprice! Is beryllium toxic in it's solid state or when they made the dome was toxic?

Vapor deposition on copper mould was the procedure back in the '80s.

 

[Bigears]

The NS-1000's were sold in mirror image pairs, it appears you have to right speakers (the serial number will indicate this). You should have your wood guy fix this before he goes any further refurbishing the cabs. Perhaps remove and flip the speaker baffle on one cabinet?

 

[Cosmin2000]

Bigears, you have pointed right. I know I do not have the L & R speakers (mirored pair), but this aspect is not an issue for me at this moment. Your suggestion is interesting, but I will not cut the baffle and reglue it backwards... I will do more harm than good with this operation from the structural point of view.

 

[born2tech]

maybe you could find a single damaged or blown mid on the net and use it for a test base for cleaning.

 

[elektronror]

I cleaned my midrange with water and soap. Worked well and it still looks healthy.

 

[Cosmin2000]

Soap and water?! Seems like returning to the basics is the way to go with the beryllium domes.

elektronror, could you please attach some pictures with the final result?

 

[donprice]

Thanks for your post, donprice! Is beryllium toxic in it's solid state or when they made the dome was toxic?

Vapor deposition on copper mould was the procedure back in the '80s.

Yes. Occupational exposure is how modern poisons are usually identified. Gloves and a little common sense should be protection enough.

http://en.wikipedia.org/wiki/Beryllium_poisoning

 

[Cosmin2000]

New pictures with the enclosures refurbish work (new veneer applied). More work must be done though...

 

[elektronror]

Didn't see your post until now Cosmin2000. Sorry for that.
Attached is a picture of the dome.

 

[Cosmin2000]

Thanks for the picture, elektronror! Yours looks almost like new. I will try your "secret" formula a.s.a.p.

 

[Cosmin2000]

The first mid range is cleaner (a lot of dust/dirt....:scratch2. Seems like some signs of dirt will not go out. I uses baby wipes and even dish detergent for the beryllium dome. Other suggestions to remove the non removable marks (see last pictures)?

 

[Cosmin2000]

The second mid-range looks better than first one after cleaning.

 

[Cosmin2000]

And, finally, some pictures with the two cleaned midranges.

 

[Cosmin2000]

The first bass driver receives some cleaning. A ton of dust behind the protective metal cover which, by the way, must be repainted due to the rust here and there. I'll move now to the second bass driver and give him a dust free appearance.

 

[Cosmin2000]

In the meantime the enclosures are almost ready (the finishing touches are to come).