The BBC LS3/5

The LS3/5A is perhaps the best-known of all the BBC's monitor designs. The BBC needed a small monitor that was suitable for critical assessment of programme quality in cramped OB vehicles and control rooms, and nothing suitable was available commercially. At the same time, a separate research project - an investigation into acoustic scaling of studios - had developed a miniature loudspeaker, and it was realised that it could be adapted for monitoring use. After much developement, the original LS3/5 was born.

Initially, 20 units were built in-house for field trials, but upon deciding to build another batch, it became apparent that KEF had altered both of the drive units, and the new units were sufficiently different to the originals to affect the way the loudspeaker measured and sounded. As a result, significant re-engineering work had to be completed by the BBC's Designs Department, and this was such a significant deviation from the original model that the A suffix was added.

The new B110 needed to be decoupled from the baffle in order to prevent an interacton with the cabinet. Next, when fed from the existing crossover, the new HF unit exhibited significant colouration which required modifications to the crossover and the addition of the familiar protective grille and felt pads. The small number of loudspeakers from the original batch were now considered obsolete, and the true LS3/5 was never manufactured commercially.

While the revised LS3/5A sounded very similar to the original, many felt at the time that the original loudspeaker was better. Could this version be re-created today?

Graham Audio presents the ultimate version of the most famous of all the BBC loudspeakers, and is doing so under one of the most cherished names connected with the LS3/5A: Chartwell. The bespoke drive units and crossover networks are developed by Derek Hughes working in conjunction with Volt and Seas loudspeakers to produce a fully licensed loudspeaker using the very finest materials available.

Specifications

System 2 Way, sealed enclosure
Enclosure Thin wall construction, 9mm birch plywood, removable rear panel
Finish Real wood veneer
Dimensions (w/h/d) 18.5cm by 30cm by 16.5cm
Weight 5.3kg
Frequency response 70Hz to 20kHz, ±3dB
Nominal impedance
Sensitivity 83dB SPL (2.83V, 1m)
Maximum output 95dB for a pair at 2m
Bass/midrange 110mm Bextrene
Tweeter 19mm dome tweeter
Recommended amplifier power 25 to 50 watts unclipped programme

Downloads

PDF File IconLS3/5 user guide - contains recommendations for setting up, using, and caring for your loudspeakers.

Reviews

  • Hi-Fi Advice - July 2020

    “Between the LS3/5’s and the LS3/5A’s, I think some people will perceive the newly made 5’s as more natural or organic while other people will prefer the more widely known 5A’s relatively more neutral and linear midrange delivery. Personally, I’m still on the fence and switching from one pair to the other remains a matter of adjusting. The technical perfectionist in me prefers the LS3/5A’s more neutral midrange while the music lover in me is more passionate about the LS3/5’s fuller and richer midrange. I say: just listen for yourself! ...Naturally, the bass goes substantially deeper and also feels more solid. But the biggest surprise for me is how flawlessly the subs pair with the monitors. The crossover point is clearly well-chosen and the transition absolutely inaudible. Tonally, the woofers are also an ideal match. This is the great benefit of using same-brand speakers that are made for each other. You get a natural synergy that you don’t get quite as easily (or at all) when adding a universal subwoofer. ...The case for the SUB3 subwoofers is not at all ambiguous. They simply provide what one hopes from subwoofers but rarely gets: a meaningful extension of the speakers’ bass range in a seamless and wholly synergistic manner.”

    Hi-Fi Advice - July 2020
  • Tone Audio - February 2017

    “While the legion of LS3/5 owners, with numerous variations on the theme, might grouse at the thought of this, I prefer the new Chartwell LS3/5 to any of the originals I’ve yet experienced. And for what it’s worth, I’ve held the first LS3/5 in my hand, at the now defunct Kingwood Warren branch of the BBC, so you know I adore these little speakers. ...I suggest buying a pair. Right now.”

    Tone Audio - February 2017
  • Hi-Fi Pig - July 2016

    “I didn’t want to stop listening. As a child hearing my father playing Glenn Miller I was carted off back 40 years, and didn’t want to end my dream. The fun in “In the Mood” just made me smile. Each soloist, especially the saxophones that made Glen Miller sound so unique and the piano, too, was detailed and very authentic, and I never once felt that the lack of bass below 60Hz a problem. Indeed the pounding bass at 2’35” of “The Hunt of Baba-Yaga”, Pictures at an Exhibition, Mussorsky, would put to shame many speakers at double the size.”

    Hi-Fi Pig - July 2016
  • » More reviews can be found in our Reviews section