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Current Market Price? JR149s

Indeed - I heard the RS4 many moons ago and just didn't like it. I seem to recall they came top in a magazine review at the time beating BC1's and 104ab's - it may have been by Jimmy Hughes but can't be certain (long time ago). I do coincidentally remember also reading an article by a reviewer (again it may have been Jimmy Hughes) who warned against wearing a digital watch with an alarm in the same room as the speakers you were listening to, because the 'speaker' in the watch, which was located under a tiny grille on the face in many of these watches at that time, would vibrate sympathetically with the drivers in the speakers you were listening to at the time and this would 'colour' the sound quality. Whether it was true or not, I have no idea. I didn't care for digital watches and never owned one to test this theory but sounds like a load of old bunkum to me.

JMH was also also a Belt fan. I think he once wrote that he listened to his speakers with the drivers pointing away from him rather than towards him.

Naturally in those days having a phone in the room ruined the sound.
 
Wiring a tweeter “out of phase” is not at all unusual in many speaker designs as some crossover slopes shift phase by 180 degrees or more, plus in a conventional flat baffle wooden box the drivers are not time aligned as the bass unit motor is a inch or two behind the tweeter. The important thing when replacing or repairing a speaker is to get it back as it was designed.

PS The classic alnico Tannoy dual concentrics (Silvers, Reds, Golds, HPDs etc) all have the treble and bass unit at opposite phase in order to time/phase-align the horn compression driver which is right at the very back of the huge magnet well behind the bass unit. It is rather more complex than that as there is a fairly compilated crossover to be factored-in with all its phase shifts, but at the most basic level for a positive input the bass unit moves backwards and the compression driver forward.
 
JMH was also also a Belt fan. I think he once wrote that he listened to his speakers with the drivers pointing away from him rather than towards him.

Naturally in those days having a phone in the room ruined the sound.

Peter Belt wasn't all bad. I owned a pair of his PWB Electrostatic headphones. Very good they were, too.
 
Yes, thinking about it, the T27 is too old to have been using ferrofluid. The T33 did use it and I bet many aftermarket swaps for the T27 did too

Partly true, the T33 - SP1074 did not utilise ferrofluid, however the T33 - SP1191 ( developed for the 104/2 ) did utilise ferrofluid.
With Kef it's always important to use the SP coding rather than speaker 'generic' name e.g. B200, B110, T33, etc. The T27 most definitely did not use ferrofluid.
 
Less often now as people have got wise to its short lifetime. Many shops must have been caught out with it sticking in display stock.
They can't be very good salespeople then if they are lumbered with stock of loudspeakers for so long that the ferrofluid used in the drive units hardens!
 
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They can't be very good salespeople then if they are lumbered with stock of loudspeakers for so long that the ferrofluid harden used in the drive units hardens!

I don't have to worry about things like ferrofluid, thank goodness. My BC1s have lasted decades without it...
 
Great thread. My 149s haven't turned up yet and while I bought a JVC AX4 I made the mistake of testing it on my teenage daughters TD160/A60 system. It's got an MC cart and the MC setting on the AX4 really made a difference. Now they want the AX4 leaving the A60 for the system the 149s will go with! I believe that's not a bad match, it's a small room.

I do have a couple of newbie questions;

How easy is it to recap these things? I have little soldering experience but can turn my hand to most things. Do you need special solder? Or should I be paying someone to do that?

Also, how can I test that the drivers are in spec? I've read Tonys 'revisiting the JR149' thread with interest but most was above my head. I don't mind purchasing additional equipment to test them if it's not too expensive. I'm really wanting to get them back to spec if possible and finding how far they are out would be the first step.
 
How easy is it to recap these things? I have little soldering experience but can turn my hand to most things. Do you need special solder? Or should I be paying someone to do that?

It is really easy assuming you can solder. Buy the Falcon cap set linked upthread and my advice is work around one crossover at a time, one capacitor at a time as it is easier to make sure you are putting the right one in the right place. Loudspeaker caps are bipolar, so they don’t need to go in a particular way round. The crossover obviously needs to be removed, and assuming you have the same version as me it is an easy job - gently pull the white plastic connector up to release the cabling, undo the center bolt thing, and then give the crossover a gentle rotational jiggle as there is also Blu-Tac like stuff holding it down that will need to be freed before it can be removed. Just be gentle as you don’t want to crack anything. I’d also go fairly easy when desoldering so as not to over-heat the board as you don’t want to lift any tracks, though I had no issues at all.

Also, how can I test that the drivers are in spec? I've read Tonys 'revisiting the JR149' thread with interest but most was above my head.

If they sound good and sound the same as one another I’d assume they were ok. If when panning pink noise or a good mono recording between them the sound markedly different you may well have an issue. I’d recap them first and set the tweeter balance pot on the crossover exactly mid-way in its travel (it has very likely been moved by someone over the years, though it might be worth noting where it was set, mine were up full for some reason!).

Basically they should sound superb, mine surprise/shock pretty much everyone who hears them. If they sound thin, shouty, dull or whatever then you may have a problem.

PS They like to be fairly close to a back wall on decent stands.
 
Measure the speakers with REW with a PC gooseneck microphone before you make any changes. The Left and Right should be matched.

The original crossovers used 60/40 solder, so easy to work on.
 
Yes, just use standard solder. I don’t like the lead-free junk available now so I’d recommend the old style 60/40 stuff. It is still available and as I do so little soldering I’m not going to make myself ill or anything. It just seems to flow far better.
 
....I’d recommend the old style 60/40 stuff. It is still available and as I do so little soldering I’m not going to make myself ill or anything....
I have never come across a safety problem with the reel type solder, even the ladies working on production lines using it 6 days a week.
There seem to be more problems with lead free due to the higher temperature releasing more fumes from flux and plastics.
There might be risks with solder paste, wear gloves handling that.
If there are hazards with 60/40 solder, it is in the disposal, especially if incinerated, but my own suspicion is that the ban was just to be seen doing something. The organic lead in petrol is a completely different issue.
 
I have never come across a safety problem with the reel type solder, even the ladies working on production lines using it 6 days a week.

The H&S line is inhalation of fumes carries some risk, there are guidelines that can be googled-up from all over the world. For hobbiests such as us I suspect it is of absolutely no concern (e.g. I probably only solder something every couple of months). I’d not want to work full-time on an assembly line using lead solder, lead poisoning is not fun. I’ve not found anything indicating a statistical risk factor though. I’m certainly not shifting to lead-free!
 
Yes, just use standard solder. I don’t like the lead-free junk available now so I’d recommend the old style 60/40 stuff. It is still available and as I do so little soldering I’m not going to make myself ill or anything. It just seems to flow far better.

I use Multicore solder from the late ‘80s, given to me by the Head of Electronics in the University Dept. where I
worked. They had to go over to more environmentally friendly types.
It flows beautifully. I wouldn’t want to use anything else.
 
My JR-149s have a couple of stripped threads in the alloy face plate for the Bass driver 's.
Any recommendations in the best repair method ?
Should I just glue a nut on the back?
Another question should the drivers have gaskets as mine didn't
Alan
 
I’d have thought gluing a nut on would be fine. They should have gaskets, the ones that actually come with the Kef units (at least mine did).
 


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