The great 104/2 refurb!

[UV101]

Some of you may know, I picked these up from Rob (hoopspntoast) end of last week. They were a little tired looking (as described in his advert) but I could see some potential. Having spent a considerable amount of time listening to this model quite a few years ago I was looking forward giving these a listen. They sounded pretty good on my Jungson I must admit, but something is a little lacking from how I remember these.....not a problem....more on this later.

Anyway here's the post I put in the original sale thread. A few have expressed interest in the work so far so i'll expand a bit ;)

Well I got them in and set up for a listen and they sound very nice on the Jungson in the living room. Pretty much as I expected.

The plan was to use them in the workshop (well spare room since the last housemove) but they are a bit bigger than I remembered and so don't quite fit and they are a little on the overkill side for living room rears!!! I think the plan will be to give the cabs the treatment they deserve and repair the dink and dents in the real wood veneer. As Rob stated in the ad, they were a little tired.

I've ordered soft and hard wax repair sticks to deal with the scuffed corners. The cabs and grills have otherwise cleaned up very well including dealing with the paint spots. I've be burred and painted the spikes and also ordered new binding posts as the originals were loose on 4mm plugs. I've also established the cause of an intermittent problem (I think you said it gave you issues recently Rob?). The cable was fractured where it attaches to the back of one of the binding posts!

Anyway, a couple of pics of the work in progress!
Left hand cleaned and sorted, right hand still to do.
http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/b403be97532351be61f88f0388fd30a8_zps6793f2a1.jpg

Top before
http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/8d4543309cbf28c7a76164f58d70ccfa_zps0542bccf.jpg

Top after
http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/f8747c28fbf0def8e719ed47eab1831d_zps3d776ad7.jpg

Left before and right after
http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/becd2e257fdd280aa18643c4bfc2f827_zps64102e60.jpg

The photo's really don't do the transformation justice! :)

[Roy S]

Nice work Ian. You tried out the 761s yet?

[UV101]

only to test when I 1st got them. When I saw these 104's I really hoped I'd shoehorn them into the spare room which I'm setting up as my workshop but they are too big!!

The Missions will most likely end up being the weapon on choice in that room supported by as sub if needed! Hopefully i'll have it all up and running this weekend. Then I can crack on with these kefs and the other couple of projects on the burner! :)

[istari_knight]

I may have missed it but how did you "revive" that black ash veneer ? I've heard of using black shoe cream but never tried it... I normally just use beeswax polish which does a good job but cant remove scratches like you have.

[Thing Fish]

I recently used cherry blossom shoe liquid on some black ash speakers I was selling and they came up like new...:)

[UV101]

I'm trying to get a bit of a pictorial together but basically its a combination of a black paint pen, sharpie type marker, a stanley blade (to get the foreign paint splashes off) & Black shoe polish.

1st I want over the whole cabinet with the blade to remove any paint spalshes, then I used a combination of the paint pen and sharpie to cover any imperfections. Next up was the shoe polish applied with a stiff brush working it into the grain. That was then buffed with another softer brush then polished in 2 stages with a soft cloth.

There are still some dings to sort and i'm waiting for the black hard and soft furniture wax for that. You melt the hard wax into any dents and level it while its not quite set. Same process as you use on laminate floor repairs (which ive done before ;) ).

Basically its all about taking your time and getting it as good as you can. I plan to repair the bottom corners with the hard wax. I also cleaned all the internals too. The cones were dirty and although you cant see them normally, if you look through the port to inspect the donuts, you can obviously see the bottom cone.

Out of completeness I also went over the base plates, screws, bolts and spikes etc.

The grill which was pretty dirty was also done with the brush and shoe polish inside and out after a very thorough hoovering obviously being careful around the badges.

I also spotted that one of the cables connected to the binding post was hanging on by the skin of its teeth and as the posts were a little worn, I've replaced them.

Overall the sound from these is exceptional but a little subdued at the top from what I remembered of them. I've done a fair bit of research on these and other Kefs previously and I know at this age, the ferrofluid in he tweeters would have been more like glue. I know I can replace these with Morel units and a minor mod but I've seen quite a few places cal replace the fluid so I did a bit more research.

Bottom line is both tweeters are now free of gunk!!! :D I've not replaced the fluid yet (I need to order some from the US) but I know some people have modified tweeters by removing the fluid so provided I don't thrash them, I've got no issues running them with while I'm waiting.

Only got one speaker completed so far but here's a few pics. (treble is much better now too :D )

I'll do a post of before pics then a post of after pics :)

[UV101]

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/550b3988c3ee4ae0cb2cedea1a24c27a_zps43609b7c.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/54bfa874802cef05988d92faaa8affbc_zps63fb0bd8.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/c849486945298d7f13e6245a40f5adc9_zpsec54b4c4.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/2a91e72fef926cf95589593529bb5f66_zps945ea356.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/4d12283ba67a2e183406c55f2f32c4a7_zps5a5e799f.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/675b9c45cca46d12b24ce67b957bc753_zpsddf8268c.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/5d11acd190f047340693a656bb093cfa_zps1598ca5e.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/4ff170df3747bfdb952505268883efe4_zpsbe93b1f0.jpg

[UV101]

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/d4018782134d1eea635c1eecabc32bf6_zps263dcf9c.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/9ae3840fdf0a84da8ca04781e612ef7d_zps72f03760.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/0041ab39adf88cd17b053e81aa664018_zpsb6629f9f.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/e649655dba4152c87f027b29841a722c_zpsde81883d.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/106b078a67ba28bbef6dbb6c0bd2fe94_zpsb0973dfb.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/feebc2854e43b2ad492cbffa4f26200d_zps9d48486c.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/7151675aab8c124efb105ea0507f3c8e_zps24ab18a0.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/f4905953387e2f4822a9af14f0b6cfd5_zpsebc54fb5.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/a0ca848b76b8923cf94d3a3b36ef01ee_zpse5313159.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/fcb91b74a79b970ad7dd86d14c7b36eb_zpse8f3eda7.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/b6c4009a291194a5b708a39efa9af2e5_zpsab6ef594.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/3d1cc01a03714a0412b36044960bc56c_zps0ea19891.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/d10b7d5563fe6a6ed8167a39edfd53f8_zps4e6f912f.jpg

[UV101]

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/40f816a65fbec9becdee38ae261cffc3_zps0f0b8201.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/d09cff7817b7cbafa269358e1148f8d4_zpsfc90e9a0.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/7125bfa4a56d247be6d2ba7e1da0ba60_zps2f5ee8a6.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/c65c4e7d229c12ed617ba0066ae46453_zps9a66ced5.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/96fb537f6321e04558f6569be3f6cab7_zps73cac07c.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/42361bd37c9cba874ea969f8d9ee6eb2_zps321730e9.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/9f326414dfc288de412cc1a30295f0f9_zpsfbf0897b.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/8168bc4a67cb8be014bf0eef6de19caa_zps64c68842.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/156fef6ed44d25ec1ca925fcb20487f2_zpsa95e7e6c.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/7e5f5ccbc87145b0c533bf7698b68f45_zps1ac87216.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/c27bf6c59e126540a79571308d972110_zpsf17ca629.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/9cd53a3c904bda5e6e9306fc554b64d6_zps811a308c.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/db427727e7708e91b6051e16f85dc360_zps9d417f64.jpg

http://i497.photobucket.com/albums/rr332/Trunky1812/Kef%20Reference%20104-2/6c44df7e1f1cfafc3b620f222c99a645_zps99161eee.jpg

[Alex_UK]

Wow - looks even more of a transformation in those pictures. :)

[hoopsontoast]

Amazing work!

I had been told to check the tweeters for dried out fluid but never got round to it.

I recon you have doubled their value at least! :)

[UV101]

Cheers guys.....

Hopefully i'll get a good go at the other speaker this weekend. Must say I'm pretty happy with how they are turning out.

[synsei]

A lovely job Ian ;)

[walpurgis]

They're looking very good. Nice work!

It may be best to replace the ferrofluid (ferrous colloid) in the tweeter coil gaps. It provides cooling and without it the power handling will be reduced, also it damps the tweeter diaphragm movement. I don't know what viscosity/spec would be used, KEF may advise. I'm sure somebody supplies something suitable.

[Andrew B]

Can't tell you how much I'm enjoying reading this. The pics are outstanding and really bring your experiences to life. Well done mate and thanks for letting us share. You're an inspiration:)

[nat8808]

:thumbsup: for the T33 photos.

I've never seen or properly understood where the ferrofluid is or how it dries up etc until now.

It's all so easy when you just go ahead and do stuff ... far too many doubters and fearmongers out there busily putting people off repairs.

[UV101]

Thanks guys :D

I get an immense amount of satisfaction from all of this and hopefully I'll inspire others too. Whilst I appreciate not all things are as straight forward as you might hope, the fact that there are mere mortals selling refurbed T33 units suggests to me that its probably not as difficult as you'd think.

Doing some research, I've come across various people claiming improvements running tweeters without ferrofluid and also the reason for using it is to aid heat dissipation. Obviously the fluid also adds some damping which is why probably why people report a difference in sound without the fluid.

I've found some details with respect to the spec of the original fluid but its looking impossible to buy in small quantities. I emailed Ferrotec and they pointed me at parts express but it seems that they don't offer the spec. It seems the best I'll be able to do is get something thats tweeter specific rather than educational grade stuff which seems to by widely available on the internet.

One good thing with the T33 is that there are 4 locating points when you sit the voice coil/silk dome back in the magnet. Doesn't seem to be any issues with getting it back exactly where it should be.

If you look at what is widely accepted as a replacement for the obsolete T33 (the Morel MDT29 or MDT298) you can buy replacement voicecoil/silk dome assembly from Morel. Clearly its a service part :)

Anyway, not sure how the serviced tweeter will end up comparing to the original but I'd bet its going to be a lot closer to the original spec than a 25 year old unit gummed up sticky muck!

[walpurgis]

I can't find a supplier for ferrofluid (there has to be one out there somewhere), but here's a link to an interesting site if you want to try making some.

http://www.popsci.com/diy/article/2009-09/making-ferrofluids-work-you

[DSJR]

If the two tweeters are sounding ok and not too sharp or dull/bland, then PLEASE leave the fookin' things alone. I don't know if replacement tweeter modules are available now for these and after all this work, it would be a tragedy if they were fugged up by trying to fix what ain't broken, if you get my drift chaps.....

[Dingdong]

If the two tweeters are sounding ok and not too sharp or dull/bland, then PLEASE leave the fookin' things alone. I don't know if replacement tweeter modules are available now for these and after all this work, it would be a tragedy if they were fugged up by trying to fix what ain't broken, if you get my drift chaps.....

One of the things with Kef tweeters of that era is that the sound goes dull over time. Mostly due to loss of ferrofluid.
If it was me I'd clean the magnets out and recharge them with new fluid.

[UV101]

If the two tweeters are sounding ok and not too sharp or dull/bland, then PLEASE leave the fookin' things alone. I don't know if replacement tweeter modules are available now for these and after all this work, it would be a tragedy if they were fugged up by trying to fix what ain't broken, if you get my drift chaps.....

Problem is I'm not sure you'll find a pair that aren't knackered now & the T33 has been obsolete for a long time. These were well and truely gummed up (as you can see in the previous pics) and didn't sound as they should. I've done a serious amount of research into these and already taken the view that if needed, I'd replace with Morel MDT298 (which is documented as a definite upgrade) but felt that these were worth attempting to save. I've now ordered some replacement ferro fluid which hopefully is similar to the original spec albeit I can only find a single reference to the original spec which may or may not be accurate. I'd be very surprised if what I have done will have made things any worse. Obviously its a delicate job and not for the fainthearted and there is always risk involved in damage to the voice coil assembly during the process.

As stated stated previously, the Morel drivers have replacement voice coil assemblies available. When you look at it, there's not much too it and as long as you get the voice coil placement correct during the assembly process there is little else to it. I have ensure that orientation is maintained in order to try and get the reconstructed state as close to the original.

As stated, if all else fails, they'll get an upgrade :)

[walpurgis]

Yes, I think the replacement of the ferrofliud is a good idea. It gives you the chance to get the speakers back into a condition where they are less likely to blow a tweeter and if the fluid viscosity isn't too far out they should sound OK.

At least you have guide lugs to enable you to relocate the diaphragms into their correct position.