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Revisiting Jim Rogers JR149s

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For the top caps, I ordered two mdf circles.

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Veneered and dyed.

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Finished product.

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I fixed the top with some 3M VHB double sided tape, 0.6mm thickness, there is still a very thin gap between the hadboard and top, I hope this will not be a problem, and might have to seal it somehow.

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Trial fit of the new foams, they look really good.

Still need to get a hardboard circle laser cut for the second speaker and fix the top, but almost there!
 
Really good work! I’d not spot those as altered at all. Fascinating to see them with the caps off too, I’ve never had reason to remove mine.
 
Interested in trying a pair of these out - never heard a pair !

They would be for use in a fairly small listening room - 9’ x 15’ - and will have to be used 6 inches or so from the front wall.

Music taste is eclectic and I do occasionally like it loud! What can I expect with a pair of JR149 ?
 
Music taste is eclectic and I do occasionally like it loud! What can I expect with a pair of JR149 ?

You can certainly expect eclectic, they are happy playing any genre IMO, but high volume will hurt them. They only have a 5” B110 bass-mid, which whilst advanced technology back in the 1970s, can’t break the laws of physics. A lot depends on your choice of music, but the more bass-heavy the less available volume as you’ll just bottom-out the 110s. If you really want high levels then a sub with a high-pass filter is an option (i.e. actively filter out the low bass from getting to the 149s which will dramatically reduce cone excursion).
 
Thanks for the reply Tony.

How would they compare to say a pair of S3/5R2 in terms of bass response, tonal balance and dynamic headroom ?
 
How would they compare to say a pair of S3/5R2 in terms of bass response, tonal balance and dynamic headroom ?

I’ve got a pair of S3/5R in the TV room. The JR149s sound rather more dynamic and alive to me, though that may just be that they suit the amps I’ve used to compare (Leak valves, 303, Pass Aleph 3) a little more. They are an interesting comparison, I really like both. FWIW I view the S3/5Rs as an absolute bargain at their second hand £500 or so for a mint boxed pair. They may not have quite the resolution of LS3/5As or JR149s, but they are superbly balanced and just get right out of the way without drawing any attention to themselves at all. The perfect TV speaker IMO, I drive mine with a slightly modified 303 and it is a very natural and articulate sound. The Spendors do have a slightly larger bass-mid as well as it being of a later technology so I’d expect a good bit more volume capability, but this doesn’t interest me so I’ve never pushed any of them. I never want to hear a little speaker play loud, that is what big speakers are for!
 
Spotted these stands as part of an ebay auction. If somebody was clever enough to be able to build these I'm sure a few on here could be interested.
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These appear to be a very late pair of mk1s as the crossovers are fitted with the same grey electrolytics and grey-wrapped inductors that are found in the mk2. They must also surely be one of the very last mk1s still sporting their original, albeit understandably crumbling, Declon foam grilles!

www.ebay.co.uk/itm/354146673106

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Had a big listening session with 3 pairs of JR149s yesterday. The purpose of this was partly to try to determine if any of the 6 speakers was audibly out of spec.
The JRs were all used as the mid and treble of a 3 way semi-active system. This allows the speakers to perform to the best of their ability and tends to highlight the characteristics compared to using them full range.
Pair 1 and pair 2 have been recapped using Falcon Audio's kit of electroytics and pair 3 has been recapped using Monacor poly caps. Pair 3 is still being renovated and was run without the mesh cover over the drivers and without the foam sleeve.

In summary Pair 1 and 2 sounded indentical. Pair 3 sounded slightly smoother, clearer and more open. Further investigation with all combinations of the mesh and foam sleeve strongly indicated that the mesh has a negative effect on the sound. We ran out of time to see if the Monacor'd crossover sounds different to the Falcon'd ones.

We also tried a pair of LS50 Metas. The sound was noticeaby different to the 3 pairs of JRs. More hifi and less music is how I would describe the Metas.

The owner of these speakers also has 2 pairs Spendor LS3/5As. We didn't bother to listen to these as the JRs have been preferred every time we tried the comparison in the past. The LS3/5A seems to cross over to the LF less seamlessly than the JRs and the upper-mid squawk is more apparent.

Our fairly unscientific conclusion is that B110 and T21 don't audibly drift out of spec... or if they do they a drift in a similar manner.
The other conclusion (again!) is that JR149s are cracking speaker when very well integrated with an LF system.
 
Had a big listening session with 3 pairs of JR149s yesterday. The purpose of this was partly to try to determine if any of the 6 speakers was audibly out of spec.
The JRs were all used as the mid and treble of a 3 way semi-active system. This allows the speakers to perform to the best of their ability and tends to highlight the characteristics compared to using them full range.
Pair 1 and pair 2 have been recapped using Falcon Audio's kit of electroytics and pair 3 has been recapped using Monacor poly caps. Pair 3 is still being renovated and was run without the mesh cover over the drivers and without the foam sleeve.

In summary Pair 1 and 2 sounded indentical. Pair 3 sounded slightly smoother, clearer and more open. Further investigation with all combinations of the mesh and foam sleeve strongly indicated that the mesh has a negative effect on the sound. We ran out of time to see if the Monacor'd crossover sounds different to the Falcon'd ones.

We also tried a pair of LS50 Metas. The sound was noticeaby different to the 3 pairs of JRs. More hifi and less music is how I would describe the Metas.

The owner of these speakers also has 2 pairs Spendor LS3/5As. We didn't bother to listen to these as the JRs have been preferred every time we tried the comparison in the past. The LS3/5A seems to cross over to the LF less seamlessly than the JRs and the upper-mid squawk is more apparent.

Our fairly unscientific conclusion is that B110 and T21 don't audibly drift out of spec... or if they do they a drift in a similar manner.
The other conclusion (again!) is that JR149s are cracking speaker when very well integrated with an LF system.

Thanks for sharing your impressions, always good to here others' experiences with the JR149, even if they're at odds with mine!

Perhaps I've just been unlucky in my purchases but I've owned five different pairs of JR149 mk1 over the years (3 pairs at the same time at one point!), and they all sounded and measured differently above 3kHz, and it wasn't just a case of the HF pots being set differently. One pair I owned had an unusual 'step down' in the FR at 3.5kHz which I hoped a Falcon ALCAP kit would fix but it didn't (see here). Another pair had an inexplicable hump in the midrange which I never got to the bottom of (see red line here). The two pairs of mk1s I've kept are relatively similar sounding but I'm pretty sure I'd still be able to tell them apart in a blind test, one is a little brasher in the upper mids and softer in the highs than the other (see here). I don't think I'd be able to tell my mk2 models apart as these sound and measure very similar to each other.

Your comment on the B110 squawk being more apparent in the 3/5A would also appear to be at odds with the general consensus. I certainly hear more colouration in this region from the JR149 than in the Falcon Q7 I auditioned last year (in fact I didn't hear any upper midrange colouration from the Q7).
 
Mine didn’t even match as a pair! Hugely out. Speaking to Jerry at Falcon implied this was quite normal after this time, though I think mine were at the extreme end of it as there was some evidence of tarnish/moisture damage.
 
I am hoping that the owner will do some measurements. He certainly has the equiment, but probably not the time.

All my comments relate to speakers used as part of a 3-way system. Used on their own the outcome might be different.
Initially we thought pair 2 was sightly brasher in the upper mids than pair 1, but after they had been run for 20 mins or so this seemed to mellow out a bit.

We certainly didn't notice any issues with the location of the stereo image, so pair matching was at least adequate. My pal really missed the lack of air (vertical dispersion?) with the JRs compared to the LS50Ms, I didn't find this to be of much consequence. Strange because I really don't like the "letterbox" sound of his ESL63s, whereas he is OK with them.
FWIW, neither of us were fans of P3ESRs when I borrowed a pair a few years ago (same config: top 2/3 of a 3-way semi active system).

I would very much like to try some Q7s, but not enough to actually buy some :).
 
To remove unscrew the nut in the middle. Should be 5 caps per xover
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Thank you for your reply. I have already unscrewed the base nut, but I don't know how to remove the pcb from the rod.
As you can see from the pics, there are four capacitors of which only two are electrolytic, the other two are polyester. Instead of the fifth capacitor I see a metal connection.
In addition, one resistor looks burnt.
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Think of the threaded silver alloy piece as a nut on the rod. It unscrews and can be removed. There is even a hole through it so you can get an allen key or other suitable item in there for a bit of leverage. Don’t worry about the rod tension, there is another nut out of view beneath the board for that so you won’t knock anything out of tension.

Once the threaded alloy part is removed you’ll need to gently move/twist the crossover around a bit as it is stuck down with something similar to Blu-Tac which takes a bit of nudging to break free. Obviously be careful with the wires.
 
Think of the threaded silver alloy piece as a nut on the rod. It unscrews and can be removed. There is even a hole through it so you can get an allen key or other suitable item in there for a bit of leverage. Don’t worry about the rod tension, there is another nut out of view beneath the board for that so you won’t knock anything out of tension.

Once the threaded alloy part is removed you’ll need to gently move/twist the crossover around a bit as it is stuck down with something similar to Blu-Tac which takes a bit of nudging to break free. Obviously be careful with the wires.

Thank you.
How about the missing capacitor?
 
How about the missing capacitor?

There were several changes over the lifespan of the speaker. I’d not attempt to alter anything, just replace what is there like for like. That looks like a red-logo era crossover to me, no tweeter fuse etc. I’d definitely keep it stock spec.

PS I’d leave the film cap and tropical fish too, just change out the two black ones with the red ends as they’ll be *way* off by now. The others should be fine. Check everything is identical left and right too as mine actually had an error on one side, one resistor was wrong from the factory!
 
Yes, they are Red logo. I will only change the two electrolytics, sorry I didn't check earlier because I bought the kit with five capacitors! I should probably also change the resistors, one looks burnt out to me. They look to me like (clockwise) 12, 5.1, 5.1, 22. Two watts Kiwame?
 
I should probably also change the resistors, one looks burnt out to me. Two watts Kiwame?

I’d leave them be unless you spot an error or see evidence of heat damage. They are almost certainly fine, and they are good quality. I only swapped all mine as there were differences in brand and even value left/right and I’m just too crazy obsessive to accept that!
 
I’d leave them be unless you spot an error or see evidence of heat damage. They are almost certainly fine, and they are good quality. I only swapped all mine as there were differences in brand and even value left/right and I’m just too crazy obsessive to accept that!

I'll check them
 


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