Restoration of KEF 103/4 speakers

IanW

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I recently inherited my father-in-law’s KEF Reference 103/4 speakers; these are very special to me. When I first started seeing my wife, we did the introduction to the parents thing and my to-be father-in-law was so proud of these 103/4 speakers. We both loved HiFi and these speakers were often discussed and listened to.

Having got the speakers home and fired up, I realised that they are need of some serious TLC. I feel compelled to restore them to the full glory. Cosmetically the speakers are in great condition, but they need: bass divers re-foaming, crossovers re-capping and the tweeters need new ferro fluid.

So here we go. . . . .

  • The new foam has arrived
  • The capacities have been ordered
  • Tweeters have been removed and will be sent away this week
  • Crossovers have been removed.
Pictures below are before I started.

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Update from today’s tear down.

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I’ve read about classic KEF speakers, sadly not listed to them.

Bet they are great. I hope you get them working again.
 
Deliberately taking it slow and easy.

Today’s job, removing the internal bass drivers, B160 SP1275.

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Got the tweeters apart in preparation for the ferrofluid replacement. Not a seamless job, one of the voice coils got knocked and needs some reshaping.

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First crossover re-capped

First crossover with old Caps, laying everything out to make sure I have everything. Good job too, as two caps were missing, these are now on their way.

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Not able to get hold of a 12uF cap, so these will be replaced by two 6uF
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All caps in place, now to trim up.
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The replacement 2x 6uF glued together for tidiness.
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All tails trimmed
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All new caps in place
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recap on left old on right
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recap on left old on right
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Assembled back into speaker terminal housing - internal
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Assembled back into speaker terminal housing - external
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Pretty pleased given that I never do soldering, now I just hope it works!!!
 
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Good god. That’s a big job.

I don’t have the steady hand for such a recone job.

I hope you do sir.

I have had to rebuild a couple of Scanspeak tweeters, D2905’s, years ago (about ten I think) a massive pain to perfectly recircle them (if that’s a word).

Still working gloriously today though. Right now in fact.

So patience and swearing loudly and frequently do pay off 👍

Excellent speakers, and once perked up they’ll last another dozen years at least. Best of luck.
 
Ps, I might mention that it’s really necessary to buy the best ferro fluid there is.

The cheap stuff is just shit. To be plain.
 
Good god. That’s a big job.

I don’t have the steady hand for such a recone job.

I hope you do sir.

I have had to rebuild a couple of Scanspeak tweeters, D2905’s, years ago (about ten I think) a massive pain to perfectly recircle them (if that’s a word).

Still working gloriously today though. Right now in fact.

So patience and swearing loudly and frequently do pay off 👍

Excellent speakers, and once perked up they’ll last another dozen years at least. Best of luck.

I’m actually cheating on the re-coning and putting the tweeters back together, I have given them to Paul at Wembley Loudspeakers. I ordered the foam kits from Audio Friends and the ferrofluid from Willys HiFi.
 
Interesting thread. Keep the updates coming.
 
Two crossovers fully re-capped. 🤓

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I’m actually cheating on the re-coning and putting the tweeters back together, I have given them to Paul at Wembley Loudspeakers. I ordered the foam kits from Audio Friends and the ferrofluid from Willys HiFi.

Far and away the best idea.

Wembley loudspeakers have been doing this for decades.

I think they’ll need all their skill with those bass drivers 😳

I shed a tear when I first saw your pictures 😂 and they’re not even mine.

Looking forward to seeing the finished job, and I can’t see how they won’t sound as good as the day they were made.
 
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So near and yet so far!

Got the speakers back from Wembley Loudspeakers and started the re-build.

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Unfortunately sounds like there is an issue with the mid-range on one of the speakers, lots of distortion. The only flipping thing not to be serviced!!

Will call Paul at Wembley tomorrow, looks like another trip required for the mid-range units.

Ian.
 
On a more positive note, the bass sounded amazing!!!
 
So near and yet so far!

Got the speakers back from Wembley Loudspeakers and started the re-build.

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Unfortunately sounds like there is an issue with the mid-range on one of the speakers, lots of distortion. The only flipping thing not to be serviced!!

Will call Paul at Wembley tomorrow, looks like another trip required for the mid-range units.

Ian.

Looking good Ian. 👍

What a pain with the midrange though. 😑😑
 
Whoop whoop, all working! Nothing wrong with the uni-q mid-range cone, it was the tweeter terminal that was sitting a little proud. Bit of delicate filing and all sorted.

OMG, they sound AMAZING, just like I remember.

Can anyone recommend some speaker stands to lift by a few inches?
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Can anyone recommend some speaker stands to lift by a few inches?
Expensive but highly regarded brand:


Best check the weight loading - the KEF's look weighty. And top-plate dimensions, of course.
Great job, by the way.
 
Whoop whoop, all working! Nothing wrong with the uni-q mid-range cone, it was the tweeter terminal that was sitting a little proud. Bit of delicate filing and all sorted.

OMG, they sound AMAZING, just like I remember.

Can anyone recommend some speaker stands to lift by a few inches? View attachment 1816294

Excellent news. They look new and sound as good as new, a first class job sir. 👍
 
Strange picture of a KEF uni-q, missing the tweeter whilst testing.
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Great job, glad you are now enjoying them. Kef Reference of this era were excellent, one of my biggest Hifi regrets was selling my 104/2’s and the 44/405.2 I ran them with, Kef and Quad Reference of that era was a dream.

As for lifting them, you could get a couple or four chopping boards either granite or wood with some 2” rubber hemisphere feet. If you are handy with a saw then you could buy some 40mm solid oak/beech kitchen worktop off cuts and just cut to the same size as the speaker, paint black if you want. You may even find a local kitchen shop that has off cuts for sale that will cut to size.
 
Yes good shout, I have some kitchen granite left over that I will measure up.
 
Whoop whoop, all working! Nothing wrong with the uni-q mid-range cone, it was the tweeter terminal that was sitting a little proud. Bit of delicate filing and all sorted.

OMG, they sound AMAZING, just like I remember.

Can anyone recommend some speaker stands to lift by a few inches? View attachment 1816294

Have you tried slightly higher front feet relative to the rear ones?

The slight tilt that allows may be all you need.
 
Have you tried slightly higher front feet relative to the rear ones?

The slight tilt that allows may be all you need.
That’s a good idea, will give that a try.
 

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