SpeakerTalk Forum Index SpeakerTalk
This forum has been set up to facilitate discussion of 1970s KEF speakers and drive units. The owner of the Forum has no connection with KEF Audio.
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

104aB repairs
Goto page 1, 2  Next
 
Post new topic   Reply to topic    SpeakerTalk Forum Index -> KEF Speakers from the 1970s
View previous topic :: View next topic  
Author Message
illoquent
Junior Contributor 10+


Joined: 08 Jun 2010
Posts: 18
Location: MK

PostPosted: Thu Nov 04, 2010 12:14 am    Post subject: 104aB repairs Reply with quote

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
Back to top
View user's profile Send private message
proffski
Über Contributor 1000+


Joined: 22 Aug 2003
Posts: 1297
Location: Tewkesbury UK

PostPosted: Thu Nov 04, 2010 9:27 am    Post subject: Re: 104aB repairs Reply with quote

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
Back to top
View user's profile Send private message Send e-mail
illoquent
Junior Contributor 10+


Joined: 08 Jun 2010
Posts: 18
Location: MK

PostPosted: Thu Nov 04, 2010 9:41 am    Post subject: Reply with quote

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.
Back to top
View user's profile Send private message
illoquent
Junior Contributor 10+


Joined: 08 Jun 2010
Posts: 18
Location: MK

PostPosted: Thu Nov 04, 2010 10:26 am    Post subject: Reply with quote

just spotted this thread!

http://www.hifiloudspeakers.info/speakertalk/viewtopic.php?t=32
Back to top
View user's profile Send private message
illoquent
Junior Contributor 10+


Joined: 08 Jun 2010
Posts: 18
Location: MK

PostPosted: Fri Nov 05, 2010 1:09 pm    Post subject: Reply with quote

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?
Back to top
View user's profile Send private message
audiolabtower
VIP Contributor 500+


Joined: 06 Jan 2009
Posts: 544

PostPosted: Fri Nov 05, 2010 3:44 pm    Post subject: Reply with quote

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.
Back to top
View user's profile Send private message
audiolabtower
VIP Contributor 500+


Joined: 06 Jan 2009
Posts: 544

PostPosted: Fri Nov 05, 2010 3:48 pm    Post subject: Reply with quote

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?
Back to top
View user's profile Send private message
proffski
Über Contributor 1000+


Joined: 22 Aug 2003
Posts: 1297
Location: Tewkesbury UK

PostPosted: Fri Nov 05, 2010 6:32 pm    Post subject: B139 Reply with quote

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
Back to top
View user's profile Send private message Send e-mail
illoquent
Junior Contributor 10+


Joined: 08 Jun 2010
Posts: 18
Location: MK

PostPosted: Fri Nov 05, 2010 7:05 pm    Post subject: Reply with quote

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!
Back to top
View user's profile Send private message
proffski
Über Contributor 1000+


Joined: 22 Aug 2003
Posts: 1297
Location: Tewkesbury UK

PostPosted: Fri Nov 05, 2010 7:48 pm    Post subject: Reply with quote

illoquent wrote:
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!


Shocked Somebody been standing it in front of a radiant heater?
_________________
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
Back to top
View user's profile Send private message Send e-mail
illoquent
Junior Contributor 10+


Joined: 08 Jun 2010
Posts: 18
Location: MK

PostPosted: Fri Nov 05, 2010 7:54 pm    Post subject: Reply with quote

God only knows! They are very much run down. Any suggestions on resolving this?
Back to top
View user's profile Send private message
proffski
Über Contributor 1000+


Joined: 22 Aug 2003
Posts: 1297
Location: Tewkesbury UK

PostPosted: Fri Nov 05, 2010 8:39 pm    Post subject: Reply with quote

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


At the frequencies that the ABR works at is it that important I ask myself, any rattles or suchlike on swept tones?
_________________
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
Back to top
View user's profile Send private message Send e-mail
audiolabtower
VIP Contributor 500+


Joined: 06 Jan 2009
Posts: 544

PostPosted: Fri Nov 05, 2010 11:21 pm    Post subject: Reply with quote

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
Back to top
View user's profile Send private message
SaSi
Senior Contributor 200+


Joined: 24 Aug 2008
Posts: 223

PostPosted: Sat Nov 06, 2010 12:47 pm    Post subject: Reply with quote

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.
Back to top
View user's profile Send private message
illoquent
Junior Contributor 10+


Joined: 08 Jun 2010
Posts: 18
Location: MK

PostPosted: Mon Nov 08, 2010 11:11 am    Post subject: Reply with quote

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.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    SpeakerTalk Forum Index -> KEF Speakers from the 1970s All times are GMT + 1 Hour
Goto page 1, 2  Next
Page 1 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group