Any Fans of the Rogers LS3/5A?

[schwarcw]

I've been playing my friends Rogers LS3/5A with my Fisher X-1000 and my Scott 222B. The Rogers are 15 ohm, frequency range 70 - 20K Hz. The are left a little huring in the low frquency. But voices, and mid range bloom sound fantastic. This old BBC design is still manufactured by Stirling, Spendor and Harbeth. None of these versions are cheap.

Steve Hoffman uses a set of these in his studio for mastering. The sound of these speakers is as honest as old Abe. No coloration, pure reproduction the way the musicians sound in the studio (except the low end). Nice speakers, who else owns a pair?

http://i126.photobucket.com/albums/p97/schwarcw/RogersLS35A004.jpg

http://i126.photobucket.com/albums/p97/schwarcw/RogersLS35A012.jpg

http://i126.photobucket.com/albums/p97/schwarcw/RogersLS35A010.jpg

http://i126.photobucket.com/albums/p97/schwarcw/RogersLS35A011.jpg

http://i126.photobucket.com/albums/p97/schwarcw/RogersLS35A018.jpg

[Marantz 500]

I love the LS3/5A, but I unfortunately don't have a pair. I do have a pair of Kef Reference 101 speakers, which are similar in size, use the same Kef drivers and sound very, very good. Extremely detailed and correct, and at the same time very sweet and easy to listen to. Just bought a pair of Quad II monoblocks to use as amplification for these speakers. The speakers have sounded great with a Marantz 170 DC and an old but good Technics receiver, so I'm hoping this will be an even better combination.

http://www.kef.com/history/1970/model101.asp

[markus]

I had a pair of Chartwell LS3/5a's for a while and know what you mean about the midrange. I ran mine off a little Advent 300 and really enjoyed them - it didn't hurt that the phono stage on the little 300 was VERY nice.

I never got a chance to hear them on tubes, but I can believe they'd sound very sweet (imagine the midrange of the LS3/5a coupled with the midrange of the globe 45 tube!)

Mine now reside with a really nice guy in Hong Kong - If I come across another pair, I'll be keeping them for sure :yes:

[Robie]

They are a speaker I would buy in an instant if I were to come across a pair but they are very pricey. I'd love an Advent receiver too. Closest I have gotten to the LS3/5s thus far is a pair of Spendor SA2s but that's not very close.

Interesting story about how they were designed but I can't recall it well enough to relay.

[mech986]

See www.ls35a.com for details and history.

Also the Yahoo! LS3/5a newgroup has a lot of information also.

http://tech.groups.yahoo.com/group/ls35a/

Also, search AK using the search engine or Google for LS3/5a and you'll find a ton of information, including a number of my lengthy posts.


Regards,

Bart
Yahoo! LS3/5a Newsgroup Moderator and Enthusiast

[BrassTeacher]

I love the LS3/5A, but I unfortunately don't have a pair. I do have a pair of Kef Reference 101 speakers, which are similar in size, use the same Kef drivers and sound very, very good. Extremely detailed and correct, and at the same time very sweet and easy to listen to. Just bought a pair of Quad II monoblocks to use as amplification for these speakers. The speakers have sounded great with a Marantz 170 DC and an old but good Technics receiver, so I'm hoping this will be an even better combination.

http://www.kef.com/history/1970/model101.asp

I also own a pair of KEF Reference 101 speakers, and I love them! The cabinet is indeed roughly the same size as the LS3/5a, but the material of the cabinet is MUCH more dense, and the crossover is mounted outside the cabinet in a concealed chamber at the bottom.

The Reference 101 may actually be better for some listener's preferences, as the crossover is designed to be flat across its range, without the "BBC dip".

In other words, I would suggest tracking down a pair of KEF Reference 101. If you love the sound, you would have a better idea if coming up with the funds for the LS3/5a is worth it. Right now, the Reference 101 can be had for approximately 1/4 the price of even a cheaper pair of LS3/5a. The cool thing would be, no matter which pair of speakers you wind up liking the best, you'll always have a spare set of perfectly matched drivers if you need replacements!

[botrytis]

I have a set of Rogers LS2's - very nice and more dynamic than the LS3/5A.

[Frihed89]

I do not own the original Rogers. I do own the newer Stirling Brodacast LS3/5A V2. They have a BBC license to produce these. I drive mine with a set of 25 Wpc Quicksilver mini-mites, 50 W Rogue Atlas and 50 W Blue Circle SBM Monoblocks. They sound great with all these amps. These are the speakers in my "main" system and I wouldn't give them up for all the tea in China.

[JohnVF]

I've heard the Spendor 'version' of these. A gentleman at Saturday Audio here Chicago walked me through a speaker-placement demonstration with them in a small room, with them running off of some nice tube equipment. Wow..that's about all I can say. Those little speakers sounded absolutely amazing, completely disappeared, sounded full and dynamic...only lacked a bit in the lower regions (but not as much as I would have expected). I think, given a small room (which I don't have at the moment), I could live with these as my main speakers.

[BrassTeacher]

Oh, Just in case this information is helpful, the moniker "LS3/5a" is a design specification of the BBC. In theory, every speaker meeting the LS3/5a specification, which is AMAZINGLY thorough (As in I wish everything made was held to these standards), should sound exactly like the prototype model, regardless of manufacturer. It should even be possible to have one speaker by Spendor, for instance, and another by Rogers as a stereo pair, and there be NO audible difference between the two speakers. If there is, one of them is out of spec. The only real "freedom" the manufacturers had in building the speakers was crossover design and layout, just as long as the frequency response matched the prototype from top-to-bottom. The overall impedance of the speaker could vary, 8 or 15 Ohms, but not the sound. All the cabinets had to be built exactly the same way, regardless of who was building them, and they all HAD to use KEF drivers, the T27 tweeter, and the B110 woofer.

Oh, they could choose their favorite color of veneer tho! :)

[mech986]

I also own a pair of KEF Reference 101 speakers, and I love them! The cabinet is indeed roughly the same size as the LS3/5a, but the material of the cabinet is MUCH more dense, and the crossover is mounted outside the cabinet in a concealed chamber at the bottom.

The Reference 101 may actually be better for some listener's preferences, as the crossover is designed to be flat across its range, without the "BBC dip".

In other words, I would suggest tracking down a pair of KEF Reference 101. If you love the sound, you would have a better idea if coming up with the funds for the LS3/5a is worth it. Right now, the Reference 101 can be had for approximately 1/4 the price of even a cheaper pair of LS3/5a. The cool thing would be, no matter which pair of speakers you wind up liking the best, you'll always have a spare set of perfectly matched drivers if you need replacements!


While I would agree that most people find the KEF Reference 101 (or R101) to be a very good speaker, it is built to a very different design brief than the LS3/5a. The cabinet uses a different set of materials (veneered MDF instead of Birch plywood) and has a stiffer construction. While that may seem "better" (owing to the fact it was designed 3-4 years after the LS3/5a), the LS3/5a cabinet was the result of extensive studies by the BBC Engineering department into cabinet material behavior. The lossy thin wall, damped cabinet has been proven to be a good performer in the speakers that use that design (BC1, Harbeth ML-1, Most Spendor and Harbeth speakers) properly implemented of course. The KEF speaker cabinet was somwhat easier to build and less costly.

The crossovers is substantially different in that it was computer designed and then tweaked and incorporated the S-STOP overload protection, an important consideration for a small monitor in the era of growing power amps. However, for some, the S-STOP circuitry was not always as transparent as desired and a popular modification was to disable that part of the circuitry. Also, the placement of the crossover in a cavity below the speaker sometimes put it at risk for microphonics.

The Tweeters in the R101 are T27's that are computer matched to each other but it is unclear if they meet the BBC spec for T27's used in the LS3/5a. The R101 woofers are different being the B110B SP1057, a newer type of the B110/B110A SP1003 used in the LS3/5a. Also the LS3/5a's woofers were closely specified at one end of the B110 SP1003 production spectrum leading to only about 10 to 30% of production meeting BBC Spec. While the SP1057 is a very good woofer, it is not a direct replacement for the LS3/5a 15 or 11 ohm woofers as the crossover is not tailored for it. It will operate and sound "OK" but will not be in specification for frequency and amplitude response.

Hope this helps clarify a bit.

Regards,

Bart

[Marantz 500]

Thanks, mech986, very knowledgeable description of the differences and similarities between the two speaker models!

[shrinkboy]

doesn't somebody now market a kit?

ah, yes. www.av.gini.com

[Marantz 500]

Looks like a nice kit, but of course it can't be real LS3/5A's since the specified Kef drive units are no longer manufactured. Does it say somewhere what drive units are used?

[titan57nl]

I have owned 3 pairs of Rogers LS3/5a the last 6 years.....And i feel stupid i sold my last set. This is the best speaker i ever had .....and i have had some.

This little wonder is simply so stunning musical....the lack of bass isnt an issue anymore.

I loved it with the sony TA-5650....because this amp is so pure in tone.

[sealy]

Last pair I saw listed sold for well over $1500

[Bauhausler]

I bought a pair of teak Rogers LS3/5As new in 1978. They were my main speakers for years and I still have them. I recently sold a walnut pair for a friend for about $2K.
In my shop system I use a pair of Fried R speakers with the same cabinets and drivers (Kef T27 and B110) as LS3/5A. I'm driving them through reproduction 15 Ohm crossovers. About as close as you can get to the real thing for cheap.
The tonal accuracy of the speaker is great. The B110 is one of my favorite drivers and I've owned 5 different pairs of speakers that used it.
The drawbacks are power handling, dynamics and dispersion. They absolutely will not play loud. They're drastically limited in their ability to convey dynamic scale in music. Very compressed sounding. There is only one small 'correct' listening position where the speaker sounds its best. Also, there's a bass bump around 120 hz and a steep dropoff below that. In anything but a very small room a subwoofer is a must with these.
They work well in my shop and they'd be OK for a bedroom system but in a typical American 2-channel home music system their limitations make them unworkable for a lot of music.

[MunkeyQ]

Looks like a nice kit, but of course it can't be real LS3/5A's since the specified Kef drive units are no longer manufactured. Does it say somewhere what drive units are used?
As Bauhaus said, they use the T27 tweeter and B110 Bextrene-coned woofer. There were two versions of the B110 made - one with a larger magnet than the other, and the LS3/5a uses the big magnet one.

T27s are used in quite a lot of other Kefs - the Reference 104, Cadenza, Corelli and Concerto to name a few.

And the B110 just seems to appear everywhere too. :D


Note that to help the low end, matching stereo subs were available using the B100 racetrack driver in a 3rd order bandpass enclosure. They're very rare, and I came painfully close to acquiring a pair for very little...

[mech986]

As Bauhaus said, they use the T27 tweeter and B110 Bextrene-coned woofer. There were two versions of the B110 made - one with a larger magnet than the other, and the LS3/5a uses the big magnet one.

T27s are used in quite a lot of other Kefs - the Reference 104, Cadenza, Corelli and Concerto to name a few.

And the B110 just seems to appear everywhere too. :D


Note that to help the low end, matching stereo subs were available using the B100 racetrack driver in a 3rd order bandpass enclosure. They're very rare, and I came painfully close to acquiring a pair for very little...

Hello,

Could you advise the manufacturer of these matching stereo subs you describe above and any other information related to them? I'm not aware of any specific sub using the KEF B139 oval (racetrack appearing) sub that were of commercial manufacture specific to supporting the LS3/5a, especially from the original licensees of Rogers, Chartwell, Audiomaster, RAM, Spendor, Harbeth, KEF, Stirling, and Richard Allan.

there have been any number of DIY type designs for subwoofers using the B139 including the Coffin dual transmission line (similar to the Fried H), as well as the IMF trasnmission lines that also used B139's with similar variations of LS3/5a type midranges/tweeters in an integrated design.

Rogers did produce some subwoofers/bass extenders such as the LSB-1 and AB1's for use with the LS3/5a. There are some very rare Rogers subs that were essentially prototyped but they used a large SEAS driver, not KEF. Harbeth also produced a type of bass extender sub as well.

Regards,

Bart

[Tedrick]

Could it be that the Reference 102 was the KEF model that was built to the LS3/5A specification? I seem to recall reading that somewhere, but can't be certain. The pair I have look very much in terms of cabinet size and driver complement like the speaker photos that were posted by the OP.

The R102's are great speakers. I've enjoyed my baby KEFs for over 18 years now. They have always astounded me with the amount of nice clean bass that can come from such a small cabinet. I use mine in my office system now to listen to classical and jazz when I'm working :music:.

[David Wrubel]

I've heard the Spendor 'version' of these. A gentleman at Saturday Audio here Chicago walked me through a speaker-placement demonstration with them in a small room, with them running off of some nice tube equipment. Wow..that's about all I can say. Those little speakers sounded absolutely amazing, completely disappeared, sounded full and dynamic...only lacked a bit in the lower regions (but not as much as I would have expected). I think, given a small room (which I don't have at the moment), I could live with these as my main speakers.


I have a pair of Spendor 3/5 speakers matched as my main speakers in a small room, and I am completely satisfied with them.

[Marantz 500]

Kef reference 101 is closer to the LS3/5A than the 102 Model is. Kef R102 uses a different tweeter (T33) and a different woofer (B200), R101 has a T27 and a B110.

[kbuzz]

I use a 15 ohm vintage pair of chartwell 's in my office system for 3-6 hours a day. All I can really say without resorting to stereogeek speach is that there is a reason they have a cult following.

PS- There is a sweet spot with power on them. Too much and you may fry the drivers, too little and they can sound weak. Personally, i like them with more rather then less power but they seem to keep their magic with most amps from about 15 watts and up.

[Damage]

What about the KEF Model 101? Does anyone know where this one fits in?

[SaSi]

The pics on the first post are not the original BBC monitors. I've read that a newer design meeting the same design goals was made using different drivers more recently.

[mech986]

The pics on the first post are not the original BBC monitors. I've read that a newer design meeting the same design goals was made using different drivers more recently.

The OP/first post's pictures are Rogers LS3/5a 15 ohm speakers, built to the original BBC LS3/5a commercial production specification, in walnut. They are lacking the Rogers grille badges but otherwise conform to the specified parameters including the KEF B110 SP1003 bextrene bass/mid with Neoprene rubber surround and KEF T27 SP1032 tweeter with glued on perforated metal protection grille and antidiffraction square felt at the grille edges around the tweeter. The Tygan grille appears genuine with velcro attachments and the sometimes Rogers added pull tabs. The only thing we don't see here is a back panel photo for verification of the Rogers Label and serial numbers.

Regarding newer designs with different drivers, only the Stirling Broadcast LS3/5a V2 (version 2) and the very recent new Rogers International LS3/5a have TRUE BBC approval to conform to the BBC LS3/5a specification of frequency and timbre response using more modern non-Kef drivers as the KEF drivers are no longer available.

There are many other LS3/5a copies, wannabees, and sometimes frauds which trade on the shape, size, look, and even name of the LS3/5a (one recent one is called the KS3/5a) to otherwise influence, suggest by association, or even outright dupe people into thinking they're getting something close to a genuine LS3/5a or copy at a good price. I'll grant that some of those speakers sound good and many have some decent engineering to them too.

However, like so many manufacturers and designers do, they sometimes will tweak the design or somewhat alter its voicing in a quest to make it "better". While that is admirable, it is very hard to capture and duplicate the LS3/5a's design goal of superb vocal midrange and general excellence insuch a small package. The LS3/5a design can certainly be bettered by all manner of speakers but, in its size and packaging, it is very hard to duplicate. Even the original manufacturers found it hard to produce consistently, so tough was the specification.

While sometimes difficult and most times expensive, it is still possible to find LS3/5a's at a "decent" price. With over 100,000 pairs out there, you just have to keep looking and trying. With today's economic downturn worldwide, some LS3/5a's have recently come "down" in price, even on 'bay. (less than $700/pair + shipping), occasionally lower than that.

In the case of the LS3/5a genuine article, you do get what you pay for, and so far, the value has held up, even for a 35 year old speaker design.

Regards,

Bart
Yahoo! LS3/5a newsgroup moderator and enthusiast

[Damage]

I bump a thread and get ignored. I'm sad.

Seriously though, does anyone know where the KEF Model 101 fits in all the LS3/5a stuff?

[Marantz 500]

Kef Model 101 is the same as Kef Reference 101, it has been mentioned in this thread.

Here's some interesting info about Kef and the LS3/5A, the Model 101 is mentioned at the bottom of the page.

http://www2.kef.com/gb/about/ls35a

"KEF finally took out a licence in 1993 and produced around 4000 systems. The total number of LS3/5As manufactured (singles – not pairs) exceeds 100,000 [7], the vast majority of these by Rogers, Spendor and Harbeth."

..."the closest KEF came to making a direct competitor to the LS3/5A was in 1979 with the introduction of the Reference 101. This system used the T27 (SP1032) with the B110B (SP1057) in a 6.7 Litre enclosure with a crossover of similar complexity to the LS3/5A and the inclusion of S-Stop protection circuitry. The Reference 101 benefited from the advanced measurement and analysis infrastructure that KEF had developed throughout the 1970s."

Jake

[Bauhausler]

I bump a thread and get ignored. I'm sad.

Seriously though, does anyone know where the KEF Model 101 fits in all the LS3/5a stuff?

Same drivers, similar cabinet, different crossover. Similar performance, but among speakers of this type there are strong opinions about what would appear t obe minor differences.
All Kef products are exhaustively described and discussed on existing audio forums. Additional detail on the 101 is readily available through Google.

[titan57nl]

I dont get people overhere comparing kef speakers to the LS3/5A....that last model was created with interference of the BBC.....and as a result something completely different.

[Bauhausler]

I dont get people overhere comparing kef speakers to the LS3/5A....that last model was created with interference of the BBC.....and as a result something completely different.

A Dahlquist DQ-10 is completely different from a LS3/5A. A Kef 101 is not.

Any speaker designed with T27 and B110 in a LS3/5A sized cabinet is going to be VERY similar in performance. It has to be. There are differences but in the larger scheme of things they are minor ones and all of this family of speakers have a great deal in common.

[titan57nl]

Have you ever listened to the LS3/5A? (with respect)

This little one is something special...must have something to do with the complicated electronics inside.

[Damage]

Kef Model 101 is the same as Kef Reference 101, it has been mentioned in this thread.

Jake

I was not aware they were the same thing. But after looking at the Reference Series brochure....

[Bauhausler]

Have you ever listened to the LS3/5A? (with respect)

This little one is something special...must have something to do with the complicated electronics inside.

<EDIT> Please read the thread and see which ones I now own and use, and have owned in the past.

<DELETED SECTION>

[titan57nl]

I had tons of speakers.........apogee diva, stages, calipers....martin logans....magnepans, spendor, celestion, imf, B&Ws, Kef, Elipson, Cabasse, you name it.

funny i end up with a set of tiny LS3/5As.....and not some small kef speakers.....all i wanted to say.

No problem what soever.......just stating my outcome. (experience)

And yes...i have read your thread...no offence meant to you.....just very sure of my case.

[mech986]

Hi Bauhausler and others,

Lots of speaker manufacturers used the B110/T27 combination to good effect in all sorts of sized speakers. KEF had the KEF Coda (larger box, earlier design, very primitive crossover), the Concerto (along with a B139 in a very large box, still with fairly primitive crossovers), the R101, and then the Head units for the R105 series with slightly different tweeters. Of course, the large speakers really featured the B110 as a midrange more than a bass-mid. IMF is the other maker whose use of the B110 and Elac based versions of the B110 in their TLS80 series transmission lines come to mind.

However, two or three speakers which sounded very different from the LS3/5a using the same or similar drivers include the original Linn Kan, the Linn Sara, and the very interesting active Meridian M2. These speakers were voiced very differently and had very striking design philosophies to work from.

The LS3/5a was never designed to be a high volume, ultimate full range speaker, nor should it ever be considered one. As a monitor speaker for small production spaces, it was a pretty good sounding compromise for what was produced.

During 1970-1975, as the LS3/5 and LS3/5a design evolved, BBC and British speaker design pushed towards accuracy and naturalness to sound in exchange for efficiency and power handling (due to the nature of materials and adhesives of the day). There is a certain reserve to them in the most proper British sense and that is sometimes why it is unfair to the design to compare them to newer more dynamic speakers in that what they were designed to do, they do well and not much more could be expected from them if they were to obey the laws of physics.

Most everyone could name other speakers that are "better" in almost every way to the LS3/5a. What many people might or do say, if given a choice, many would opt for a pair of LS3/5a's as their Second choice in speakers. And that's not a bad recommendation.

Of course, I'm a little biased!!

Regards,

Bart

[Bauhausler]

FYI, here's the user's info sheet for my first pair, purchased new in 1978. I'l lbe adding a bit more about my relationship with LS3/5As and related speakers in a bit.

http://www.audiokarma.org/forums/attachment.php?attachmentid=124593&stc=1&d=1229903240

http://www.audiokarma.org/forums/attachment.php?attachmentid=124594&stc=1&d=1229903240