My vintage Kef 104ab's

[Richiebuoy]

A few years ago I decided to set up a vintage hi fi system in our log cabin, partly for a bit of fun and partly to have a system that I could only dream about as a young man

I already had a Rogers A100 amp, I bought a Sony TC 399 reel to reel and a Thorens TD 150 turntable, then one day by chance I was browsing Ebay and a pair of white Kef 104ab’s (see my av) came up as a BIN for fifty quid….I bought them.

I wasn’t so keen on white but the wife loved them (half the battle) and said they almost looked “art deco”. Funnily enough I grew to like the white too.

My log cabin system was far from set up so I decided to hook up the Kef’s to my house system, a Linn Klout amp, MF cd player and some Monitor Audio MA 14 golds. Well, I got such a shock !!! the Kefs sounded far better than my more recent and much more expensive MA’s …..more musical, same bass, more detail and just so much more nicer to listen too, the only downside was there was more colouration in the Kefs but it wasn’t bad.

The Kefs stayed in place as I simply preferred them, but I kept asking myself could they really sound as good after nearly 40 years as they did when they were new. Looking round the internet I found a site dedicated to vintage Kefs, a brilliant site with so much information, even a few ex Kef workers and a couple of Kef engineers from the 70’s frequent the site.

So this is what I did to one of the Kefs, I was advised to replace all the caps in the crossovers as even if they weren’t leaking their values would have drifted after nearly 40 years, I did this with a kit of same value caps from Falcon Acoutics, I opted for the slightly dearer Solens.
I then coated all of the inside un-damped parts of the cabinets with 2mm of floor grade epoxy resin (doesn’t go brittle). I rewired them internally with silver plated OFC and added some nice gold plated binding posts.
I by-passed the contour control switch and the fuse. There is a substantial brace holding the bass/midrange (B200) speaker at the back (inside) that had shrunk, so I made some wooden shims and reinstated the brace. I also removed the lose wadding inside to make the ABR (B139) work better and it did on my concrete floors but I’m not sure this would be a good idea on wood floors.

So, I now had one updated (as opposed to upgraded) speaker and one old one. I found a mono CD for the A/B comparison, I cranked up the volume, hit ‘play’ and …… well, disappointingly not a lot, a little more bass and less colouration but that was about it, otherwise no difference. I was disheartened to say the least, although I enjoyed doing it, it all seemed a waste of time, so I never bothered with the other one.

About a year later I decided I should maybe do the other one so they at least matched, but before doing that I did another A/B test with the mono CD…..well….what a difference ! I couldn’t believe it, the updated one was now singing, a veil had been lifted, it was more open, tighter, cleaner and sweeter. I can only conclude that this was hundreds of hours (we don’t watch much TV, we just listen to music every night) of “burn in” doing its job…..I was a happy bunny.

But it's still not right for us, at moderate to high volume they are amazing speakers, especially for nearly 40 years old, but most of our listening is done whilst we chat in the evening and at low volume the ABR’s simply don’t work well enough, so I’m now looking for some Kef 104.2’s or 105’s…. sorry its been a bit long winded but that is the story of my beloved Kef 104ab's.

[Dingdong]

Try B&W DM2's. I've got a spare pair you can borrow to try. You seem fairly local.

[DSJR]

DM2's are usually not as good as 104ab's in the bass and BD139 ABR be damned! I've compared them often enough to know and using master grade material when both models were around..... Modern amps (Mini-T anyone?) may improve the DM2 to bring the bass up to the nice mid and top they have.

The 104ab ought to have some wadding in the cabinet. Loose is fine and KEF would have worked out roughly how much was needed - no amateur box stuffers there back then I can assure you. Silver plated wires aren't always ideal - you'd have saved a bomb and possibly got a better sound with Maplin 50 strand instrument wire, as used once by Epos in the original ES14's... Remember what the coils and drivers are wired with? The contour control shouldn't take anything away if the switch is clean, since the job is usually done by other components in the crossover. As for the tweeter fuse, I do understand, but keeping the fuse and holder clean used to fix it most of the time.

The main thing today is that the bass can still sound underdamped with some amps - I can't remember of the Rogers A100 is cap coupled or not? A good working Quad 44/405-2 sounded superb with these, as did a well cared for 33/303 far more recently. The power handling isn't high by modern standards and you ought to take care of these, as blown drivers may not be easy to replace (KEF's drivers of this era do vary and as you say, the best part of 40 years may not have treated their performance kindly).

I love the 104 in ab form very much. The majority of 104/2's out there are rather more modern though, as long as they've not been thrashed or mistreated, but again, all used speakers need to be treated with a little suspicion...

[Dingdong]

It would appear that our ears are very different Dave.

[DSJR]

It would appear that our ears are very different Dave.


So when did you last compare KEF104ab's directly with DM2's on plucked bass? :lol:

They're ancient relics now (albeit fondly remembered) and probably nowhere near now what they were when new - those bextrene cones do change it seems... By all means compare them and enjoy them for the excellent period pieces they are :) I speak as a fellow owner of antique speakers from 1974 (my Spendor BC2's, albeit with newer and supposedly better? bass drivers pulled from some SA2's) so I'm not trying to be patronising..

I can't help being so old that I sold these bloody things new...............:cool:

[Dingdong]

Having listened to both Dm2's and 104ab's I know which one I'd choose every time.

I continue to use the DM2's as I haven't found anything I'd rather have, despite listening to quite a few different speakers.

[DSJR]

Good. At least you've taken the trouble :)

[vinylspinner]

Not wishing to stir a hornets nest here but I have had many pairs of DM2 or DM2a speakers, used them as monitors in studio apps in the 70's, also had Kef104 ab in home hifi use from late 77 to early 82, much prefered the DM2 speakers, hence the reason why Dingdong picked up several pairs of DM2 cheap when I gave it all up last year.

Still have one pristine pair for private use, they will be staying.

Nigel

[Dingdong]

You know where I am if you ever want to move them on.


You going up to Scalford Nigel?

[vinylspinner]

Sorry Mark,

This last pair are stayers, yes I am going to Scalford, meet you at the bar :)

cheers

Nigel

[Dingdong]

Aye, look forward to catching up over a pint. No exhibiting this year, so can chill out and listen to lots of inferior speakers. ;)

[vinylspinner]

Great, I will bring proper pork pies from Wiltshire just for you.


Nigel

[Dingdong]

Sorted. I like pies. I'll pm you my number and we can sort out a pint.

What was this thread about again?

[synsei]

Nigel, don't forget to deliver the package to agent Dingdong when you see him. By the way, you have £15 in your PP account :D

[vinylspinner]

Hi Dave,

Don't worry, all sorted, mum's the word.

Nigel

[synsei]

:D

[vinylspinner]

Hello Richard,

Take up Dingdongs offer and try the DM2 speakers, you may be amazed at how good they sound.

Nigel

[Rare Bird]

I can't remember of the Rogers A100 is cap coupled or not?

They use Interstage transformers, these amps are a fav of mine :)

[synsei]

My experience with B&W's DM2's has taken yet another huge step forward and it would appear that they are not the slow, drudgy affairs they are made out to be by some. They do like a bit of valve action up 'em Matron.

So far I have driven my DM2's with three 'power' amps, a Hafler DH220, an Amptastic Mini-T and now a Delphonica Valhalla One which sports glowing bottles. The Hafler and the DM2's were not a good match. I didn't discover quite how bad a match they were until the 60 quid T-amp took its place in the system, after which I sold the Hafler on pretty quickly. Veiled was probably the best description I can come up with to describe the sound of the Hafler/DM2 combo.

The Mini-T by comparison drove the DM2's wonderfully and it was as if the two were soul mates. Gone was the stodgy bass, lacklustre mids and tizzy top end, suddenly the music was alive with detail, pace and depth, the only caveat being a tendency for the Mini-T to softly clip during dynamic bass passages at higher volumes, which is hardly surprising as it only delivers around 10wpc in real world terms. At slightly more than reasonable listening levels however the DM2's sing beautifully with this little amp.

So, to the Delphonica Valhalla we go and here is the amplifier to take the DM2's by the scruff of the neck and banish those rumours of low frequency stodge good and proper. The Valhalla does everything the Mini-T does but much, much better. Realism is how I would describe it. It's an old chestnut, but I really am hearing things in recordings I have not noticed before, really subtle things like low level mic hum, people turning pages, a foot shuffling to the rear of the orchestra. Was that a door slamming off in the distance? And all this in the most stunning 3D, which stretches well beyond the speakers in every dimension. That is how good DM2's can be when partnered with decent gear.

Well Richard, that is my entire ownership experience of the DM2's thus far and I have to say that my respect and admiration for these delightful speakers has grown as the quality of the kit which drives them has improved. Try auditioning a pair if you can, you may be very pleasantly surprised by the outcome. Oh and incidentally Richard, it is 4:28am as I write this and I have Nick Drakes album, Bryter Layter playing in the background at low level so as not to disturb the neighbours or the rest of the household and yet the dynamics of the recording are full and balanced ;)

[Richiebuoy]

Thanks for the replies and thanks for the kind and generous offer from Dingdong. I’v not heard the DM2’s but have read great things about them as I have about 104ab’s, so I think this would be a side step for me rather than upwards. I did own some DM7’s once, they were awesome but the temptation of a straight swap for a Fender Strat was too great so I lost the 7’s
.
Silver plated ofc is cheap in the small amount needed for a rewire so I used that to match the main speaker cable.
I know Kef engineers knew what they were doing with the lose wadding, but even they, as good as they were could not design a speaker that could fine tune itself to every size room, type of construction, speaker placement and preferred volume setting….speaker design's are always a compramise .....so the wadding went and they sounded better on my concrete floors or at least to my ears when I occasionally remove the olive oil soaked cotton wool.

As for amps, my previous amp was the Arcam P35, a very good amp in my opinion, but my Linn Klout is in a different league and would blow away the Quad 33/44 and my old Rogers A100 with ease in my opinion. I’m not familiar with the Delphonica Valhalla but it does sound intriguing if a little underpowered for some less efficient speakers ?

Anyway, thanks again for the replies :)

[synsei]

I’m not familiar with the Delphonica Valhalla but it does sound intriguing if a little underpowered for some less efficient speakers ?

I am going to say the same thing to you Richard as was said to me on here a while back when I posed the same question: "Ah, but them be 'VALVE' watts" :D

Now, I have not a clue concerning the technical aspects of that statement but from experience I can now confidently state that 15wpc of valve power is a raging gale compared to the Mini-T's 15wpc gentle breeze ;)

[DSJR]

Valve Watts should be the same as transistor Watts, but softer clipped :lol:

[Macca]

But the valve amp will probably struggle a lot less with supplying current when the load gets tough.

[DSJR]

Are you sure that's correct? Transformer coupled valve amps need the transformers to transform/convert much of the voltage available into current I thought, and the reputation of these amps is that the current output isn't actually very good, hence the speakers of old being around 11 to 15 ohms to minimise this requirement...

Forgive me if I'm wrong here... :scratch:

[Macca]

It depends on the valve amp in question of course but my understanding is that if the amp has a 4 ohm tap then it should not struggle with low impedence loads.

[synsei]

As I said Dave, I cannot comment technically but I can tell you that the Valhalla is delivering concert hall levels and scale right now, which is something the Mini-T cannot hope to match with these speakers. Can only speak as I find fella ;)

[hoopsontoast]

Thought the DM2's sounded great on the end of my little 10wpc A10.
The A10 had no problems with my 104/2's using the 4 ohm tap.

[Richiebuoy]

I believe that technically the ratio is around 4 to 1 ( 1 watt of valve = 4 watts of SS) however the reality is condiderably higher as valve amps have a much greater stable operating range, you can crank it right up and it will still be stable, crank an SS amp right up and it begins to hurt.

[synsei]

I have the DM2's hooked up to the 8ohm taps just now, is it worth me experimenting with the 4ohm taps or would I be heading for trouble that way?

[Dingdong]

I have the DM2's hooked up to the 8ohm taps just now, is it worth me experimenting with the 4ohm taps or would I be heading for trouble that way?

No, just leave it alone.

[Rare Bird]

Dave use the 8 Ohm tap..

[synsei]

Well that was pretty emphatic, I will leave it alone then :)

[Dingdong]

And remember not to run it without the speakers connected. You stand a good chance of fucking the o/p trannies.

[Ali Tait]

I have the DM2's hooked up to the 8ohm taps just now, is it worth me experimenting with the 4ohm taps or would I be heading for trouble that way?

It will do no harm whatsoever to try the 4 ohm tap, give it a go and see which you prefer.

[jfs]

This is only my third post on the forum. I did say initially that I would only post if I felt that I could offer some advice borne out of experience/knowledge, well here it is, for what its worth.
Some years ago I had a pair of Kef Carlton 11 speakers ( similar configuration to the 104 ), they were nice enough, but the bottom end was a little bloated and woolly, quite ill defined. This bottom end colouration impinged on the midrange making it overly warm and far too creamy sounding, probably euphonic is the word I'm looking for.
Anyway, to cut a long story short, I measured all internal surfaces and had upholsterers foam ( similar consistency to the eggcrate damping foam available ) cut to size and 2" thick. No caps, inductors or resistors were changed on the x/over. The bass tightened up considerably and the midrange sounded just as I had hoped it would. An additional piece of foam 'arched' directly behind the B200 improved matters still further. All the BAF that originally filled the cabinet went in the bin. My friend bought them off me and re-capped them with electrolytics ( they lost something when he tried polypropes ), they sound superb. If they'd been a little more wife friendly I may still have them today. In my experience BAF as a damping material kills the ability of the drivers, every time I've used the stuff I've been unhappy with the results, it gives a woolly, ill defined presentation, regardless of amount or positioning experimentation. The foam worked a treat and raised the bar regarding the speakers performance. I still listen to them at my friends, I still want them back, a forlorn hope I fear.
I've also had the B&W DM2's, I have to admit to preferring the Kefs, but then again, I like the ' Kef family sound ', but could live with the DM2's.

[Rare Bird]

Ive not had many KEF loudspeakers. I liked my old '104AB' & 'Cantata'

[Richiebuoy]

Kef 'Cantatas' are fabulous speakers but increasingly rare....

Thanks to this forum and a member called "Pete" ( a very nice man by the way) I'm the proud new owner of a pair of Kef 105's. They are all original, no mods or up dates and have not been re-capped and are in VGC.

I had not heard the 105's before but they do get some great right ups so I can only compare them with my 104ab's. The bass is a bit deeper and tighter though perhaps not as much as I expected but still good, the highs are clearer with more detail so also good. Now the mids, they sound 'boxy' or 'boxed in' ...it could be just my ears, or just how they are or maybe a problem......any idea's