SpeakerTalk

illoquent · Posted: Thu Nov 04, 2010 12:14 am Post subject: 104aB repairs

Hi

Just picked up a fairly run down pair of these and just looking for a couple tips on the initial problems:

1-The tweeter dome is dented inward, I'm sure I can find a way of popping these out but will it have a major effect on performance?

2-The bass radiator looks like the glue has gone off on the front piece, would it be possible to remove this without detrimental effect on the performance?

Cheers all

proffski · Posted: Thu Nov 04, 2010 9:27 am Post subject: Re: 104aB repairs

Pucker up your lips and suck it out...

Do you mean the aluminium foil on the ABR is coming off? Shocked

_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

illoquent · Posted: Thu Nov 04, 2010 9:41 am Post subject:

Hi, tried the vacuum on the tweeter this morning with no luck so might have to try something a bit more radical.

Well with the ABR there is a black piece which appears to be coming unstuck/has several air pockets in it. I do not know enough indepth as to whether this is the aluminium foil or not.

illoquent · Posted: Thu Nov 04, 2010 10:26 am Post subject:

just spotted this thread!

http://www.hifiloudspeakers.info/speakertalk/viewtopic.php?t=32

illoquent · Posted: Fri Nov 05, 2010 1:09 pm Post subject:

Ok so possibly looking at replacing the ABR, although i'm sure its only a cosmetic issue. Would I be able to replace the SP1042 with an SP1044?

audiolabtower · VIP Contributor 500+ Joined: 06 Jan 2009 Posts: 686

I think the SP1044 is an active unit, so has a magnet and voice coil etc. The SP1022 ia a passive with just a chunk of aluminium where the coil should be, the mass of which suits the cabinet volume and system resonance.

audiolabtower · VIP Contributor 500+ Joined: 06 Jan 2009 Posts: 686

Can you post a picture of the 139? The front often has air bubbles etc where the cosmetic surface has come away from the ?foil/polystyrene? underneath, so it could just be a matter of some glue?

proffski · Posted: Fri Nov 05, 2010 6:32 pm Post subject: B139

Remember that solvent based adhesives will have most interesting effects on polystyrene, choose with caution!
_________________
I contend that for a nation to try to tax itself into prosperity is like a
man standing in a bucket and trying to lift himself up by the handle.
-Winston Churchill

illoquent · Posted: Fri Nov 05, 2010 7:05 pm Post subject:

Well heres the images:

http://img522.imageshack.us/img522/825/imag0004ja.jpg

They are both the same, and are slightly sticky (hence the gathered dust seen here). So is clearly some kind of adhesive issue!

proffski · Posted: Fri Nov 05, 2010 7:48 pm Post subject:

illoquent · Posted: Fri Nov 05, 2010 7:54 pm Post subject:

God only knows! They are very much run down. Any suggestions on resolving this?

proffski · Posted: Fri Nov 05, 2010 8:39 pm Post subject:

audiolabtower · VIP Contributor 500+ Joined: 06 Jan 2009 Posts: 686

yes. the surround looks in good condition so if they are still airtight I would leave well alone and make some new grills if the original foams have crumbled long ago and just hide them

SaSi · Senior Contributor 200+ Joined: 24 Aug 2008 Posts: 256

How do the surrounds look on the B200? In many cases of 104s that I've seen pictures of the surrounds appear to have been stretched into flat rather than half circle.

illoquent · Posted: Mon Nov 08, 2010 11:11 am Post subject:

Yes I would say the foil is still airtight and it has no audible effects (to my ears), although the stickiness seems to be going now, which makes me think this may have been a recent issue, i may be able to smooth out some of the bubbles as it resides.

In regards to the B200, they are in places erring towards flatness but on the whole are in the half circle shape.