BBC LS3/5a Original v DIY clones

Speakers are such a bunch of compromises, you really can't beat soaking up as many as you can before making a choice.

I have heard the Falcons briefly and they are very good, beautifully voiced.

I have also heard 15ohm Rogers LS3/5a at length and have had them in my system on loan, they do some things very well and some things quite badly.

Forgive me for not relating much more, its all getting a bit hazy now because I lost all interest in DIY speakers after getting a pair of KEF LS50's :D
 
I have been in audio boutiques and listened a similar top of the line Macintosh and 802D system and came away unimpressed. It can get loud and clean. But the articulation and timing was all off and the system did not sound neutral. I also felt that there was a harshness and fatigue that bothered me. I thought it was an anomaly.

You're not alone, or rather: AH! I'm not alone! I listened to them in a showroom in Berlin with some Revox amps I believe and had to walk away. Exactly the same feeling: abrasive, somewhat obnoxious, like some prick at a party trying to constantly show how clever and erudite and generally superior they are, and thereby proving the opposite. They seemed to get in the way of enjoying any music by insisting to push your nose (ears?) into details that didn't matter. The sum of their sound was less than its parts.

I got the feeling they're engineered (like basically most show-room sold speakers, really) to impress by shock and awe within the short time span of a big-box-store visit, and because they're expensive, have to do so even more.
 
...Forgive me for not relating much more, its all getting a bit hazy now because I lost all interest in DIY speakers after getting a pair of KEF LS50's :D

KEF LS50 playground - measurements of raw drivers in factory cabinets and simulations

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How do Markaudio fare against KEF LS50

KEF%20LS50%20H%20Freq%20Resp%20Plot%20Q1.png


How do Markaudio fare against KEF LS50

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Well... you can improve it.
 
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Kef LS50 was heavily pushed on the market by used car salesmen type of campaign, but shortly after the mass hysteria, a used examples flooded the selling sites. To me, it's simply a bad speaker on the level of cheap ELAC atrocities. An old audio dealer I know was apoplectic by the fact that dozens of people called his little shop and occupied hours of his time trying to make up their mind about buying $200 speakers...
To me, a "high tech " looking transducer in the box is the clear sign to steer away .
 
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Thanks for the link to the LS50 playground, Maty. Looks like the crossover could be improved. Is there a step response measurement anywhere for the LS50?

I do not know. Ask Zvu. Probably.

BTW, Does anyone have experience with the Kef LS50? | Page 18 | Headphone Reviews and Discussion - Head-Fi.org

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More importantly, I put two layers of the Dynamite [Dynamat] on the baffle as shown to reduce reverberation directly to the driver as well as some smaller cut pieces on the other areas such as the raised lip where the driver is screwed into the baffle. In the last pic you can see some white cotton batting in the back which I experimented with replacing some of the foam but didn't find there was much of a difference so I put all the foam pieces back in, not blocking the port on the upper right...
 
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Kef LS50 was heavily pushed on the market by used car salesmen type of campaign, but shortly after the mass hysteria, a used examples flooded the selling sites. To me, it's simply a bad speaker on the level of cheap ELAC atrocities. An old audio dealer I know was apoplectic by the fact that dozens of people called his little shop and occupied hours of his time trying to make up their mind about buying $200 speakers...
To me, a "high tech " looking transducer in the box is the clear sign to steer away .

Don’t you think you are being a bit harsh here. The LS50 is not a bad speaker (by most accounts, test measurements and thousands of reviews) and coaxial driver units are indeed high tech and not a general reason to steer clear.

KEF used to sell replacement coaxial driver units to the public. But hey got wise we were just getting them for DIY so now require a serial number of the box to order a replacement.


@Maty, looks like Stereophile measured the step response here:
1212KEF50fig8-2.jpg


Time aligned with reverse polarity tweeter.

But to get back on topic, here is comparison of LS50(red) and LS3/5A in John Atkinson’s listening room at Stereophile:
1212KEF50fig6.jpg


LS3/5A has a lot more treble energy and nice shallow bass roll off from a sealed box. Seems to reach deeper than you think.
 
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I had a pair of Rogers LS3/5A's, bought when they were almost affordable (pre-kids!). When I went to work abroad in the 80s, they went into the loft and didn't come out again until last year, when I saw the silly price they were fetching on eBay. I listened to them for a few days before they went (to Hong Kong!), just to check they still worked really, and had no regrets whatsoever when I packed them up to go to their new owner.
 
Don’t you think you are being a bit harsh here. The LS50 is not a bad speaker (by most accounts, test measurements and thousands of reviews) and coaxial driver units are indeed high tech and not a general reason to steer clear.

KEF used to sell replacement coaxial driver units to the public. But hey got wise we were just getting them for DIY so now require a serial number of the box to order a replacement.


@Maty, looks like Stereophile measured the step response here:
1212KEF50fig8-2.jpg


Time aligned with reverse polarity tweeter.

But to get back on topic, here is comparison of LS50(red) and LS3/5A in John Atkinson’s listening room at Stereophile:
1212KEF50fig6.jpg


LS3/5A has a lot more treble energy and nice shallow bass roll off from a sealed box. Seems to reach deeper than you think.

yeah , I was probably little too harsh on Kef LS50 and since everybody owns them they probably have some merit to them. The marketing department did a brilliant job that's for sure.
 
I'm not going to defend my speaker of choice, that's derailing the thread, but I will present this conundrum:

How do you know how good something can be if you've only heard how bad it can be?

You have to take someone's ear/brain's word for something if you ask for general advice. You don't know how closely aligned thier preferences or experiences are to yours.

The one thing I have learned in 35 years of critical listening is that we all have differences in perception, there is no correct answer, especially when it comes to the room/speaker combination: the most compromised component in the chain. That's why there are a million hobbyists and manufacturers out there all doing something slightly different and largely, surviving.
 
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A while back, I had a series of threads where I would set up full range drivers in the same setup and record some music clips at identical levels. I then posted the clips for people to hear once downloaded. Use of good headphones was best to hear differences. The clips were not labeled and people voted on their favorite. I think it would be neat if a similar thing were done with speakers. Maybe an LS50 vs LS3/5A vs Continuum would be neat. The room acoustics and quality of chain impact sound. But requirement is all else identical except DUT. SPL levels have to be set to be equal to prevent loudness bias.

Here were the threads I made called Subjective Comparison Threads:

A Subjective Blind Comparison of 3in to 5in Full Range Drivers

A Subjective Blind Comparison of 3in to 5in drivers - Round 2

A Subjective Blind Comparison of 2in to 4in drivers - Round 3

A Subjective Blind Comparison of 2in to 4in drivers - Round 4

A Subjective Blind Comparison of 2in to 3.5in drivers - Round 5
 
It's worth pointing out that HiFi for Pleasure rang an extensive subjective evaluation of current loudspeakers in around 1978. The tests were conducted blind with an experienced panel of listeners. The LS3/5a came out third overall, surprising the writer (Martin Colloms) as it beat out established references like the BC1 and Quad.

Like all speakers, its design involves compromises; if its particular design aims suit your room, tastes and listening levels, then it's a good speaker.
 
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Some interesting graphs of the frequency response and side and back emission of LS5/3 as measured by the BBC in a research report on cabinet materials. The choice of beech fillets (internal spars) was quantified to give lower panel resonance.

http://downloads.bbc.co.uk/rd/pubs/reports/1977-03.pdf

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The B110 T27 combination was ok in the '70s, but, today? I see Falcon are selling the finished speaker for £2350 - GTFO!

Seriously, you can do a lot better for a lot less money.
The B110 is actually a pretty decent driver, especially for the time.
The T27 not so much. Tweeter couldn't handle much power and also wasn't able to cross low enough.
 
The drivers and graphs and all that shebang is of marginal importance otherwise the market would be flooded with great speakers and it's simply not the case.
Nobody has to defend their choices really (although everybody does more or less) and variety of products exists to satisfy individual choices. I'm not sure the LS3/5a has had a massive marketing campaign KEF LS50 is/was enjoying ( with mostly unspeakable retards of a car salesmen mentality involved in the process) It's just often a herd run mentality and time will tell. Any speaker I don't like is a "bad speaker" by default :)
Add to it the kind of people who promote them and the kind of crowd which buys them and the case is sealed. LS3/5 a is a timeless design for a certain acoustic spaces and a certain music. It probably can be improved upon but not by the designers of a current fashions regarding the sound reproduction and not on the given budget and merry goes round hi-fi circus and certainly not by a "one man" operations . The price is what it is. Blame the Asians or British sobs (aka snobs )
 
The 2nd hand cost of Ls/3/5as shows that they are not mere sound producers. They are collectors items, "works of art". £5000+ On eBay, for an early example that the buyer almost certainly will not hear before purchase.
It is nice to have something in the world that normal rules and logic do not apply to.