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Revisiting Jim Rogers JR149s

I didn’t realise there was one! I’ll check it out next time I set it up. The beauty of that system is I can recreate things exactly as it has a stepped attenuator!
 
Sensitivity in Watts or Volts confuses things and some manufacturers deliberately get their descriptions wrong when its in their favour.
Because you JR-149s are 16 Ohm, the Watt sensitivity is fairly good. This mattered in the valve amplifier days, as a transformer output can give a greater voltage swing into 16R
 
Toronto past 1am in the morning.
Listening to Reuben and the Dark on a Quad pre amp/ amp through to to JR 149 speakers and it’s just sounds great. “Newer” recording on a 40 plus year set up- marvellously fab.
Like seeing the graph plots and all that stuff don’t get me wrong but just listening to music you like is great.
Happy late at night.
 
Toronto past 1am in the morning.
Listening to Reuben and the Dark on a Quad pre amp/ amp through to to JR 149 speakers and it’s just sounds great. “Newer” recording on a 40 plus year set up- marvellously fab.
Like seeing the graph plots and all that stuff don’t get me wrong but just listening to music you like is great.
Happy late at night.


Yes well it’s 7 a.m. here and I’m listening to 149s through a Radford power amp, and it sounds great too - how can it be that such little boxes can be so very musical and involving.
 
Yes well it’s 7 a.m. here and I’m listening to 149s through a Radford power amp, and it sounds great too - how can it be that such little boxes can be so very musical and involving.
Agree I am amazed how good they are and how much bass comes from such a small speaker

Alan
 
I really like the JR 149's, I first heard a pair in early 1980's and was shocked as to how good they sounded connected to a Trio KA 9100 integrated amplifier and a Technics DD turntable. The imaging was super and I stayed in the shop listening to them for ages and felt sad because I could not afford them then.

I have 2 pairs of these now but MK2 versions and along with my Snell K MK1 speakers they are keepers as they do a lot of things "right" that some other speakers just don't. I think my son has his eyes on one pair of 149's so hopefully he will appreciate good sound reproduction for many years to come.
 
I really like the JR 149's, I first heard a pair in early 1980's and was shocked as to how good they sounded connected to a Trio KA 9100 integrated amplifier and a Technics DD turntable. The imaging was super and I stayed in the shop listening to them for ages and felt sad because I could not afford them then.

I have 2 pairs of these now but MK2 versions and along with my Snell K MK1 speakers they are keepers as they do a lot of things "right" that some other speakers just don't. I think my son has his eyes on one pair of 149's so hopefully he will appreciate good sound reproduction for many years to come.
MK2 as in the version with Scanspeak tweeters and Focal bass drivers, or do you mean the later 'gold logo' version of the mk1 still using KEF T27 and B110 units? If it's the former then it's good to hear some more appreciation for this often overlooked version. :)
 
Yes I have 2 pairs of the "MK2 as in the version with Scanspeak tweeters and Focal bass drivers" and they are the best sounding version to my ears but also to a dealer who was visiting my London home. He could not believe they sounded that good and he had not heard of Avondaled 32.5/140 combination. I had a few different pairs of various LS3/5a's and ended up selling them but kept the JR-149 MK2's.

One pair needs the tops rubbing and polishing but otherwise good so a project for the sunny bright days I think. I am intrigued by the Falcon Acoustics version of the 149's so it is on my radar for some time in the future.
 
Yes I have 2 pairs of the "MK2 as in the version with Scanspeak tweeters and Focal bass drivers" and they are the best sounding version to my ears but also to a dealer who was visiting my London home. He could not believe they sounded that good and he had not heard of Avondaled 32.5/140 combination. I had a few different pairs of various LS3/5a's and ended up selling them but kept the JR-149 MK2's.

One pair needs the tops rubbing and polishing but otherwise good so a project for the sunny bright days I think. I am intrigued by the Falcon Acoustics version of the 149's so it is on my radar for some time in the future.

As an owner of both mk1s and mk2s I have to agree, I feel the mk2 edges the mk1 on transparency and doing the "disappearing act".

PS - I'm not sure I'd hold my breath for a Falcon JR149, last thing I heard it was prohibitively expensive to manufacture, which is a pity.
 
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It is a pity Falcon didn’t adopt Jim Rogers’ very clever rolled alloy design for the cabinets. The whole idea of it was it was cheap to build and demonstrably better than a conventional box in many ways. The JR149 was never an expensive speaker in its day. It still baffles me that no one has ripped the idea off since and I’d love to hear what say ProAc or Spendor could do with the same cab design. I’m convinced the low-mass tensioned rolled alloy cab is far better sounding than MDF, maybe even better than screwed baffle plywood (which is the best way to build a box IMHO).
 
Because a simpe cylindrical cabinet goes against the favoured doctrine of elaborate cross-sections and massive internal bracing?

Thinking about it, a cylinder is a very efficient use of material to contain a given volume.
 
Thinking about it, a cylinder is a very efficient use of material to contain a given volume.

In the case of the 149 it is also very light whilst still being inert so doesn’t store energy the way heavy glued MDF cabs do. 149s always sound very agile and open to my ears, none of that ‘dead in the water’ thing you get from so many high-mass speakers. That was one thing that struck me with the comparison with the S3/5R, which as stated I really do like a lot, they are lovely speakers, though the 149s are just a little more alive and dynamically ’free’ somehow, and I’d put money on that being down to the cabs.

PS The S3/5R are not high-mass, and I suspect all the better for that. I’m just making the comparison I have available.
 
The speed of sound in aluminium is about 50% higher than in wood, so this must affect resonances for a certain cabinet size

Even a very thin aluminium tube,say just 1mm thick, is still very stiff compared to the internal air spring. My only concern about a very thin tube is the deformation as the driver motor basket pushes against the tube as a reaction to the coil acceleration.
 
The speed of sound in aluminium is about 50% higher than in wood, so this must affect resonances for a certain cabinet size

The damping seems very effective as they have no ‘note’ or ‘ring’ when tapped. IIRC there is some ‘deadsheet’ sort of stuff under the standard acoustic foam inside the cabs, plus they are under tension from the central metal rod, so end up very inert.
 
I've just had a message to say that my JR 149s have been rebuilt "and they sound amazing!" But he's asked me a question and I want to get your advice about what to say. The grills were fixed before with glue and staples. He's wondering whether he can just avoid messing around with the staples and use just a spot of glue in each corner. What do you think?
 
Ideally you don’t want to make the fitting too permanent just in case you need to get in again, so it all depends on the type glue! FWIW I reused the original staples and stopped any rattling with a little Blu-Tac.

PS I don’t think they were originally glued, though the damping strip stuff can get a bit sticky.
 
Getting the staples to stay in firmly can be a PITA, particularly if the grilles have been removed more than once. On one of my previous pairs I resorted to putting two strips of masking tape around the grille and cab, to hold the grille firmly in place top and bottom. JR150 grilles on the other hand are held in place by 4 bolts, this being possible because the wooden end caps screw on and off.
 
Got them. New Falcon drivers (matched woofers and tweeters) and crossovers.

They’d had a previous repair from The Croydon Audio Centre, the owner said he used to work for Jim Rogers when they were based in Croydon. He’d inserted an (unbranded) woofer the wrong way round!

http://www.theaudiocentre.com/

The character of the image is much improved, as you can imagine. The balance especially.

Tell me, will the new drivers change character as they’re played more?
 


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