I'm building a pair of LS3/5a speakers. Currently trying to decide on components. I see dozens of suggestions and parts kits available. Seems the top choice might be Falcon. But at $1000 for drivers and Xover, a bit rich for this project. On Ebay I see Taiwan knock-off drivers, and Xovers for reasonable price. But the lead time is very long.
My question:....I see crossovers offered in 11 and 15 ohms......But I'm not seeing drivers with this impedance. Do I simply use 4 or 8 ohm drivers with these crossovers and the total impedance is delivered at 11 or 15 ohms? Or do I need to source 11 or 15 ohm drivers.
Thanks in advance!
My question:....I see crossovers offered in 11 and 15 ohms......But I'm not seeing drivers with this impedance. Do I simply use 4 or 8 ohm drivers with these crossovers and the total impedance is delivered at 11 or 15 ohms? Or do I need to source 11 or 15 ohm drivers.
Thanks in advance!
What do you mean by a pair of LS3/5a speakers? A close clone of the 50 year old OB monitor using similarly poor components by modern standards? A sealed cabinet of the same size but using a modern 1" tweeter and 5.25" midwoofer to get better performance (for a computer speaker). Or something else?
Two speakers.....
I have no problem with a "Variation on a Theme" for the LS3/5a.......I sold LS3/5a way back in the late 70s so I'm familiar with the sound, and the negatives associated with it. If there are drivers and Xover that "improve" on some of the original LS3/5a sound, I'm all ears....
The nominal impedance of the complete loudspeaker is 15 ohms (or 11) however the drivers are 8R. 8R is basically the minimum impedance of the loudspeaker. The Falcon is more than a perfect replica, it's just identical with original drivers hand made in UK. Actually, the crossover components are better for obvious reasons....
What theme? They were designed by the BBC as OB monitors to be used in enclosed spaces at less than standard levels when headphones weren't an option. They have low output, no low bass, an exaggerated upper bass, a pressed steel frame resonance in the passband, strong cone resonance in the passband, variable hand applied cone doping, 50 year old tweeter with a rough response, typical flat baffle 2 way directivity issues, complicated crossover to address the many issues, lively complicated cabinet, etc...
Any modern speaker that is currently being used to do the job the LS3/5a was designed to do 50 years ago has significantly better technical performance. That's simply 50 years of evolution. Decent standard range 5" midwoofers from established suppliers like SB Acoustics are superior to the B110 in almost every respect never mind premium range drivers. Likewise for tweeters if not more so. Then there is waveguides, active crossovers, CLD cabinets,...
The appeal/theme of LS3/5a speakers clearly has nothing to do with technical performance. Fair enough since nor does the appeal of record players, valve amplifiers, exotic cables, and many other things that some audiophiles get enthusiastic about. But what is it that needs to be included in a speaker using modern components and modern design if it is to have that LS3/5a appeal? Does this speaker which is fairly widely used today to do a similarish job as the LS3/5a 50 years ago have a strong appeal to LS3/5a enthusiasts? I suspect not but I don't know why not?
https://mackie.com/en/products/studio-monitoring/cr-x-series/CR4_X.html
https://mackie.com/en/products/studio-monitoring/hrmk2-series/HR624mk2.html
My next door is a music professional; she does movie soundtracks; she uses both these.
I can't do better no matter how hard I try; especially at the price point of these and one of the reasons I make 3-Way speakers
https://mackie.com/en/products/studio-monitoring/hrmk2-series/HR624mk2.html
My next door is a music professional; she does movie soundtracks; she uses both these.
I can't do better no matter how hard I try; especially at the price point of these and one of the reasons I make 3-Way speakers
Both of you are 100% correct......It has nothing to do with the sound....it nostalgia! Like old cars. I had a 1987 Porsche Carrera.....Extremely rough around the edges. Any recent sports car was a much better handling, riding, steering, etc car........But there was nothing like that 87 Porsche! I have extremely modern speakers and electronics (KEF LS50 Metas/Magnepan LRS/Fluance 6....Buchardt i150 amplifier)....But I also have a VTA ST120 tube amp and a couple "classic" tube preamplifiers. As the mood sways me, i listen to them all. This whole LS3/5a thing is a bit of reliving my youth as I used to sell them back in the 70s. I liked them BECAUSE they were different, not necessarily better....
Ahhh well then.
You can't put a price on nostalgia, heck that is one of the reasons I build f******* big monkey coffins and use amplifiers with flashing LED power indicators.
In which case all I can say is "Good luck" and that almost any modern combination of drivers but in a cabinet clone should work and perhaps you should visit all of the current LS3/5A threads
You can't put a price on nostalgia, heck that is one of the reasons I build f******* big monkey coffins and use amplifiers with flashing LED power indicators.
In which case all I can say is "Good luck" and that almost any modern combination of drivers but in a cabinet clone should work and perhaps you should visit all of the current LS3/5A threads
I built a pair.
New Rogers cabinets with damping, foam lining and terminals.
New Falcon Acoustics components, except for T27s, which were unavailable at the time.
I was offered a pair of NOS T27s.
Help on construction from Jerry Bloomfield of Falcon & Rogers’ Andy Whittle.
OK they aren’t ‘factory built’, but are indistinguishable from a pair of 2015
Falcon LS3/5As.
I never intend to sell because they are unique and special to me.
New Rogers cabinets with damping, foam lining and terminals.
New Falcon Acoustics components, except for T27s, which were unavailable at the time.
I was offered a pair of NOS T27s.
Help on construction from Jerry Bloomfield of Falcon & Rogers’ Andy Whittle.
OK they aren’t ‘factory built’, but are indistinguishable from a pair of 2015
Falcon LS3/5As.
I never intend to sell because they are unique and special to me.
What Andy says.
I sold LS3/5A new and have been listening to them on and off for near 50 years. I don’t know where all the love comes from. Nostalgia i guess.
They were designed for a specific purpose for which they performed well at the time, but the compromises made mean it doesn’t do well at other things.
I restored a buddy’s set of Roger’s (when done client said they sounded identical to a friend’s set thay hadn’t been mutilated). When i listened to them they were kinda boxy and not very impressive. A set ofmodest FRs in a set of milliSize miniOnkn smoked them.
Today i would expect something like MA P7HD in a mPlu-Ken would provide better performance. https://www.madisoundspeakerstore.c...pluvia-seven-hd-4-metal-cone-full-range-gold/ (also comes in silver as well as the copper).
About $100 in drivers vrs the grand at Falcon, but no nostalgia, just better sound.
dave
I sold LS3/5A new and have been listening to them on and off for near 50 years. I don’t know where all the love comes from. Nostalgia i guess.
They were designed for a specific purpose for which they performed well at the time, but the compromises made mean it doesn’t do well at other things.
I restored a buddy’s set of Roger’s (when done client said they sounded identical to a friend’s set thay hadn’t been mutilated). When i listened to them they were kinda boxy and not very impressive. A set ofmodest FRs in a set of milliSize miniOnkn smoked them.
Today i would expect something like MA P7HD in a mPlu-Ken would provide better performance. https://www.madisoundspeakerstore.c...pluvia-seven-hd-4-metal-cone-full-range-gold/ (also comes in silver as well as the copper).
About $100 in drivers vrs the grand at Falcon, but no nostalgia, just better sound.
dave
Yep, what Andy said.
I am sure that when the LS3/5A was first available, it had a more natural response than most other speakers then available, at least from 200 Hz up. That is why serious listeners took an interest in it, and were willing to live with its shortcomings. The midrange and treble was more natural and more correct than what they had yet experienced. I am sure that is true for the rest of those BBC designs from 40+ years ago... they were very good in comparison to the other available speakers at the time.
I am also sure that if those BBC engineers had access to the kinds of drivers we have today, and the kind of measurement techniques and digital processing, and the advanced circuit/electrical/acoustic simulation software we have today, they would have come up with something much better than the LS3/5A.
j.
I am sure that when the LS3/5A was first available, it had a more natural response than most other speakers then available, at least from 200 Hz up. That is why serious listeners took an interest in it, and were willing to live with its shortcomings. The midrange and treble was more natural and more correct than what they had yet experienced. I am sure that is true for the rest of those BBC designs from 40+ years ago... they were very good in comparison to the other available speakers at the time.
I am also sure that if those BBC engineers had access to the kinds of drivers we have today, and the kind of measurement techniques and digital processing, and the advanced circuit/electrical/acoustic simulation software we have today, they would have come up with something much better than the LS3/5A.
j.
Of course. Actually, to a point they already had in the form of the LS3/5 [no 'a']. 'couldn't get the driver consistency. The B110 and T27 were probably the best units of their particular types & for the size / objects they had in mind available at the time & even then they were supposed to be produced using individually selected 110s (which quite clearly didn't always happen: the BBC had no production facilities & had to issue licenses to various companies, who presumably submitted 'select samples' for assessment & possibly for corporation use, & weren't quite so strict on the old QC for those that got sold elsewhere). Today -Harwood & co. would be using higher performance units. Possibly with the same approach to the enclosure; the thin-wall type does work within the context it was designed for, and assuming it's built & damped as-designed (which many aren't) it's okay and actually quite non-resonant for the objects they had.
Regarding the 15ohms or 11ohms, it's just to reflect the nominal impedance of the speaker with the first or second generation filter. The LS3/5a is a fairly reactive little thing, so this is arguably a bit moot as the load varies wildly with frequency; technically the 11ohm variations were supposed to be superior, but many still worship at the shrine of the earlier versions, possibly because of the hallowed, near-mythical early prototypes that occasionally get wheeled out for journalists &c. to bow down before. 😉
Regarding the 15ohms or 11ohms, it's just to reflect the nominal impedance of the speaker with the first or second generation filter. The LS3/5a is a fairly reactive little thing, so this is arguably a bit moot as the load varies wildly with frequency; technically the 11ohm variations were supposed to be superior, but many still worship at the shrine of the earlier versions, possibly because of the hallowed, near-mythical early prototypes that occasionally get wheeled out for journalists &c. to bow down before. 😉
Back in the day I wanted LS3/5a's but they were pricey and there were no local dealers. Pre internet by decades. So I got a pair of Kef 101's. The also used B110 and T27 drivers but in a different enclosure with a different crossover.
They were absolutely fabulous In my small aoartment and remained fabulous when I moved to a larger house and used them with a Janis subwoofer and properly set up active crossover. Anyone rember the Audio Control Richter Scale?
Anyway, the point of all this is to say that a compact speaker with the right drivers, even back then, cans sound exceptionally good as proven by the 101's. Not perfect by today's standards, but for back then better than my friends LS3/5a's that probably did not make the best use of its drivers for in home audio.
And I also echo what Scottmoose said. A good pair of moderen full rangers will probably outperform older small designs. My current near field rig uses a pair of Markaudio drivers and I'm never replacing them. Wait, did I just say that?
They were absolutely fabulous In my small aoartment and remained fabulous when I moved to a larger house and used them with a Janis subwoofer and properly set up active crossover. Anyone rember the Audio Control Richter Scale?
Anyway, the point of all this is to say that a compact speaker with the right drivers, even back then, cans sound exceptionally good as proven by the 101's. Not perfect by today's standards, but for back then better than my friends LS3/5a's that probably did not make the best use of its drivers for in home audio.
And I also echo what Scottmoose said. A good pair of moderen full rangers will probably outperform older small designs. My current near field rig uses a pair of Markaudio drivers and I'm never replacing them. Wait, did I just say that?
In fairness to Dave, he was the one who raised that, rather than myself -I didn't mention any particular driver types as I thinking purely LS3/5a.
I live near the Falcon headquarters and last year I bought at a good price as they were having a sale, an LS3/5A kit with the Gold Badge 15 ohm crossover. At the same time
I bought a raw un-vennered cabinet kit with the objective of using some similar drivers I had. These are for use in my small listening room 3.7 x 3.7m which
is a bit like a BBC OB van !
Anyway I completed the main kit but was a bit disappointed by the sound ie it seemed a bit bright to me. I adjusted the hf level in the crossover which improved it.
It has a beautiful mid range though particularly on voices which is no surprise as that's what it was designed for.
Then I built the un-vennered kit with some Jordan JX92s and Fountek ribbons with a crossover from Jim Griffins MLTL's which had the same frontal dimensions.
I mounted this externally to give a little more effective cabinet volume.
My "Son of LS3/5a" sounded much better than the Falcon's to my ears. The Jordan works a little better in the LS3/5a cabinet than the Kef's giving a little bit more
bass extension but still not at the Falcon Q7 level. The Fountek ribbon is so much better than the T27 which is a bit coarse by comparison. The combination works
very well, bass and the top end are improved while retaining the special midrange. Ive not got round to measuring both speakers yet but its something I must do.
I'm planning on building another cabinet in the same manner as the LS3/5a but with a slightly larger volume a la Q7 to get the best bass out of the Jordan's. By the way
I think the cabinet design ie heavily damped thin wall, is one reason why this speakers mid range is special. The BBC research paper shows in detail the pains they took
to minimise cabinet colourations. Its completely dead using the knuckle test, not lively at all
I see that a Monacor driver is specified as a better replacement for the Kef and there are some clone crossovers's available with air cored inductors. I may try both
in the Falcon's.
I bought a raw un-vennered cabinet kit with the objective of using some similar drivers I had. These are for use in my small listening room 3.7 x 3.7m which
is a bit like a BBC OB van !
Anyway I completed the main kit but was a bit disappointed by the sound ie it seemed a bit bright to me. I adjusted the hf level in the crossover which improved it.
It has a beautiful mid range though particularly on voices which is no surprise as that's what it was designed for.
Then I built the un-vennered kit with some Jordan JX92s and Fountek ribbons with a crossover from Jim Griffins MLTL's which had the same frontal dimensions.
I mounted this externally to give a little more effective cabinet volume.
My "Son of LS3/5a" sounded much better than the Falcon's to my ears. The Jordan works a little better in the LS3/5a cabinet than the Kef's giving a little bit more
bass extension but still not at the Falcon Q7 level. The Fountek ribbon is so much better than the T27 which is a bit coarse by comparison. The combination works
very well, bass and the top end are improved while retaining the special midrange. Ive not got round to measuring both speakers yet but its something I must do.
I'm planning on building another cabinet in the same manner as the LS3/5a but with a slightly larger volume a la Q7 to get the best bass out of the Jordan's. By the way
I think the cabinet design ie heavily damped thin wall, is one reason why this speakers mid range is special. The BBC research paper shows in detail the pains they took
to minimise cabinet colourations. Its completely dead using the knuckle test, not lively at all
I see that a Monacor driver is specified as a better replacement for the Kef and there are some clone crossovers's available with air cored inductors. I may try both
in the Falcon's.
Last edited:
Yes, very tough to beat for nearfield listening, depending on driver and box design.
jeff
Meatly amps that can deliver lots of excess current.
While looking for those, i found these, and early version and a Falcon version. These won’t sound the same.,
dave
We did a project with the BBC for a small active speaker to replicate the sound of LS3/5a. For that, we were loaned a pair of their 'Reference Standards'.
Over, the years, we had bought & listened to several pairs of LS3/5a s and thought, like Dave, "What's the fuss about?"
But those BBC standards were a revelation. I don't design speakers to sound like them but I appreciate what they were.
If you want to know how a REAL LS3/5a should sound, you need an ex-BBC one in good condition ... or the last of the KEF versions made at the end of the last Millenium.
A big factor was that when BBC, Kingswood Warren, designed it, the units they used were rather far from the mean of KEF production .. and this has been a problem for all of its life. The final KEF version was based on near standard production but used a completely different xover to get the original sound. KEF production was somewhat more consistent by that time though B110 was always difficult to get right 😊
KEF 101s,, on paper, should have wiped the floor with them. But guess what? In DBLTs, there was a small but definite preference for the BBC standards over the 101s which also did well in DBLTs
The know how to design good speakers is now much more widespread but at the highest level, there are still things we really don't unnerstan about dem beasts. And yes. I think a REAL LS3/5a is at the highest level.
IIRC, there's a web article on the history of BBC monitors explaining stuff like this and why certain design decisions were made. It goes right back to the first official 'BBC monitor' by Raymond Cook with a 12" (15"?) Goodmans bass unit and 2 x Celestion HF1300s.
Over, the years, we had bought & listened to several pairs of LS3/5a s and thought, like Dave, "What's the fuss about?"
But those BBC standards were a revelation. I don't design speakers to sound like them but I appreciate what they were.
If you want to know how a REAL LS3/5a should sound, you need an ex-BBC one in good condition ... or the last of the KEF versions made at the end of the last Millenium.
A big factor was that when BBC, Kingswood Warren, designed it, the units they used were rather far from the mean of KEF production .. and this has been a problem for all of its life. The final KEF version was based on near standard production but used a completely different xover to get the original sound. KEF production was somewhat more consistent by that time though B110 was always difficult to get right 😊
KEF 101s,, on paper, should have wiped the floor with them. But guess what? In DBLTs, there was a small but definite preference for the BBC standards over the 101s which also did well in DBLTs
The know how to design good speakers is now much more widespread but at the highest level, there are still things we really don't unnerstan about dem beasts. And yes. I think a REAL LS3/5a is at the highest level.
IIRC, there's a web article on the history of BBC monitors explaining stuff like this and why certain design decisions were made. It goes right back to the first official 'BBC monitor' by Raymond Cook with a 12" (15"?) Goodmans bass unit and 2 x Celestion HF1300s.
The Monacor drivers were used in the Roger’s 60th anniversary ls3/5a, so can be made to sound right, and are fairly cheap. The sph135tc was used in it’s 4ohm guise and the crossover was basically the standard 11ohm one with a few tweaks for a different tweeter.
A top tier ls3/5a is still pretty excellent, especially with bass extension.
A top tier ls3/5a is still pretty excellent, especially with bass extension.