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#1
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JR149 speakers
Hi all, anyone had these? I chanced upon a pair going locally the other day. Not cheap or in particularly good condition but one owner and looked like they'd spent the last 40 years in the dry which is perhaps more important. Plan is for a vintage system in the spare room.
Back home, they checked out visually and with a meter ok so I hooked them up to the main amp for a quick listen. They were on 20" stands a few feet away from me, so, near-field in the middle of the room well away from the walls. Wow are they bright - a veritable supernova of treble assaulting the ear 'oles I put it mostly down to me being used to big speakers and to them needing to be near the back wall (which they will be later). A few tracks was enough to hear that the drivers were all working and they're now in pieces for a look-see and gentle cosmetic make over! Very impressive build quality but crikey Jim Rogers certainly didn't take the established route of speaker construction did he? These must have cost a fortune to make and are a right Aladin's cave of surprises to work on. Thankfully there are some very good threads on the web with lots of info from guys like Tony L and Robert over on Pink Fish. I've got the xovers out now and testing, and the metal grilles will be off tomorrow to clean out the last of the disintegrating foam (the black outer grills are long gone but there's still the yellow stuff over the tweeter under the metal grill gone hard and powdery). The grills need to be unstapled before I can remove that and check the drivers. Plan with all old gear is to do as little as possible, not lose the patina(), but get them working properly whilst keeping them as near possible to original. To that end I agonised over keeping the existing Elcaps in the xover. Then thought, well 40 years... better lift a leg and put the meter on one or two at least. Well, the perceived wisdom is these caps dry out and lose value isn't it? None were low, ALL are over, some twice or 3 times over! The 6 3.3uFs reading 4.1uF to 8.4uF, the 2.2uFs doing best at 2.5uF and 2.8uF, and the 1.5uFs at 3.8uF and 4.4uF. Difficult to know what's happened or what value they were originally. I checked the meter against a new 2.2uF poly which was spot on. Better check the resistors and tie down the inductors with cable ties too I suppose. So new caps ordered from Falcon and some outer grill foam on the way from Wilmslow. A light sand and a couple of coats of Danish oil should tidy the woodwork... and I'd like some nice stands, speakers are 8 1/2" diam, if anyone's got any? |
#2
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Re: JR149 speakers
Hi Richard, these were a alternative to the much now sort after BBC LS3 5A and I think that they use the same drivers, I had a pair of the LS3 5A's that I bought in the late seventy's for £20.00 and sold them some 5 years ago for £1640.00 to a guy in Australia, , if and when you resurrect them, please try them in a small room, alternately, try and find another 19 pair and run them altogether in you main room . Bob
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#3
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Re: JR149 speakers
Hello Richard,
As It happens I recently sold a pair of those. They were my late father's last speakers. After sitting unused in the back of a wardrobe for many years I decided to sell them. I got a good price and they now live in China of all places. As to the caps in yours, I have read that if the internal resistance goes high, this can make the value appear falsely high on a meter. I imagine yours will improve with new caps fitted! I must admit to not being a fan of them, my pair at least. I would certainly not call them bright, in fact, I found them to be rather "midi", being rolled off at both frequency extremes. This is I expect party due to being a long time 12" Tannoy user! In particular I found their very limp dynamics to be a failing. Having said that, they were easy to listen to and would make a perfectly good pair of second speakers for a office/bedroom system, sounding pleasantly inoffensive on small scale music. Personally, I don't get all the enthusiasm for LS3/5As and JR149s. They do have a certain charm but they sound their age to me and LS3/5As are hugely overpriced. Phil.
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Commission for Dark Skies (CfDS) Last edited by Phil Y; 15th March 2019 at 03:05 PM. |
#4
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Re: JR149 speakers
Hi Bob and Phil,
Yes they are what they are but it's been a long time since I heard them so it will still be fun. They're for a vintage system, backs against the wall in a smaller room, so no problem with size. It will be good to see the old FM3 etc glowing orange again rather than it being sat on the shelf! In the late 70's I walked into a dealer who had a pair on top of a pair of Ardens playing Carnival of the Animals iirc. I naturally assumed it was the Ardens (the dealer will have his fun!) but it was the smaller speakers. The Ardens actually sounded worse when he switched, too heavy in his small room. Thanks for thoughts about the caps. Google suggests some small value bipolar electros can start to decrease their resistance as they move towards shorting rather than increase esr. Apparently cap and esr meters aren't a reliable guide for small value old caps so best just to replace. 40 years is too long I think even if they still work in some manner. All in pieces now. Removed the metal grills and cleaned off the crumbly old tweeter foam and checked the drivers. All looks fine. The inside foam damping is all springy and good and there's no sign of damp on the zinc plated parts. A bit of white belly on the B110s, is this an issue which needs sorting or just leave them whilst they sound ok? Oiled the wood and it's come up well. Should have them together again this week and will put them in the same room position to see if there's a change. |
#5
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Re: JR149 speakers
Hello Richard,
I'm sure they will be just the job for your intended use. Don't take my comments too seriously, they are just not my kind of speaker. A friend of mine who had the KEF constructor version of the LS3/5A for many years thinks I'm too harsh in my judgment of them. I still have a pair of B110s kicking around that were the midrange in a home built speaker of mine years ago. They also have the coating lifting around the dome. I have read that heat can be used to re-stick it but I have not been brave enough to try it. I should really because I could then sell them if it worked, I can't imagine I will use them for anything myself. The ones in my JR149s looked fine for whatever reason. Phil.
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Commission for Dark Skies (CfDS) |
#6
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Re: JR149 speakers
Well these are back together again and I've had several good listens over the weekend.
I re-capped them with Vishay polyesters which I've used for coupling before and they sound very nice to me. I left the metal grills off whilst checking them through as the grills are stapled in place and I wanted to be able to remove the drivers again if needed. They sound great despite a very near-field positioning. The tweeters certainly brought back memories, they have an almost electrostatic resolution seated so close. Swept frequency with a test CD and all is clean with no buzzes. The teble was still strong so I took a look at the preset adjuster. I'd marked it with a couple of dots but had not had a twiddle. Ah, it was set fully anti-clockwise which is full treble. I don't know if the factory or the po set it there but I adjusted to the mid point and it sounds much better and more integrated. It might be different again of course with foam fitted. This time, due to the mid room location rather than back to a wall, I raised bass 3dB on the preamp and the resulting sound had me listening for 3 evenings of several hours each. During the first evening the speakers changed dramatically to a fuller and more powerful sound so either they loosened up after not being used for a long time, or the caps ran in a little, or the speakers ran my ear holes in! Anyway the effect has stayed and they sound great now on 2 further sessions. Metal grills back on next and black foam has just arrived |
#7
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Re: JR149 speakers
oooh they do look nice Richard.
And interesting to note that you didnt find them lacking in entertainment value, In smaller rooms small standmounters I think can sound more pleasant especially if there isn't an excess of bass energy exciting the smaller space. Those JR 149 can fetch surp[risingly high prices, the last time I saw a pair in the local auction rooms they fetched a highish price, and they had been modded as far as I could see so lacked "originality". I dropped out when the price hit my self imposed limit and I think whoever bought them paid over the odds in view of the work needed to get them to "shop" quality. Nice work Richard, and you have kept their period character I think. There are those that don't think so much of the small monitor style speakers like these and their unaffordable BBC LS3/5A cousins but I have heard the LS3/5A sound very good indeed in suitable environments, especially considering their initial purpose as near field monitors in OB vans as far as i can ascertain. I may be wrong there. Also your use of a tone control may have the purists reaching for their nooses, but I myself feel that judicious use of tone correction does sometimes have its rightful place. In fact I have on the drawing board a plan for a subtle baxandall circuit that I could insert in the tape loop of a preamp, much as you'd use the defeat switch on a better quality amp with TC's. You may have noticed I have gone over to the "spark" side as I am collecting a pair of Quad ESL989 at the weekend to have ready for the new lounge when the builders are done. Fingers crossed that it rall integrates well in the new larger lounge. Andy. |
#8
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Re: JR149 speakers
A quick thought Richard, do you think the cylindrical design helps with things like diffraction effects and internal sound reflections that traditional boxes can suffer from?
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#9
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Re: JR149 speakers
Hi Andy, thanks and yes I could easily live with them. Yesterday I fitted the metal and foam grills, had a listen, then went back to the regular speakers which hadn't been used for a week, to compare.
I'd been listening to the JR149's near field on axis 2-3m away, with me seated 2m from the wall, and them placed 3m from their back wall. Thus it was pretty much like listening in the garden(!) - not much wall reflection for the treble and little bass boost from the rear wall. Hence a small bass lift from the amp balanced things up a bit, but the close, direct, treble from the tweeters still left them sounding exposed and distracting. Really, I had started off just checking the drivers worked but then realised the attached cables would be a pain to lengthen so I made the best of where they were for a listen. After an hour I was pretty much hooked so they stayed for the week! They were already loosening up and sounding better and with the grills on they sound better still and integrated like they had been moved back 1m or 2. I set the amp flat and they still sounded good so left it there and had a couple of hours with them. Then switched back to the usual Tannoys and was amazed how similar the sound was. I think that listening carefully for problems for a few days to the JRs had made me over-critical and I was hearing roughness, lack of clarity, etc on some tracks that was actually there but I hadn't noticed it. Cylindrical cabs, yes I suppose diffraction on the outside and damping of reflections on the inside would both be improved. The construction looks expensive but the law of diminishing returns kicks in quickly with hi-fi doesn't it and second hand prices look cheap compared with 15ohm LS3/5A. |
#10
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Re: JR149 speakers
You have made a good job of them Richard, I am not surprised you like them, I have always had a soft spot for small speakers but I am very surprised they work so good in your large room. BOB
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