Service and Spares

I get a huge amount of emails asking for help with broken BBC and Rogers speakers. This is a particular problem, and finding spares can be difficult or impossible. In some instances, your best bet might be to consider finding another example of your speaker on the second-hand market, and extract the required drive units from them. This seems like a waste, I know! And for the BBC speakers, you would need to have them measured and the crossover adjusted if you want them to be in-spec.

Potential sources of spare parts

Rogers UK can help with some models, including the LS3/5A and LS5/9.

Falcon Acoustics manufacture the SP1003 B110 and T27 tweeter used in the LS3/5A, and sell matched pairs of both, amongst other things like crossovers and grilles.

Stirling Broadcast had some Rogers spares, including dB101 spares, but these were bought from Rogers UK when it was closed down some 20+ years ago and are likely exhausted now. They do offer various options to help with LS3/5As, including baffle kits and replacement cabinets.

While you can deal with Doug Stirling directly using the contact details on his website, please note that he has an eBay shop called "Stirling Broadcast Shop".

LS3/5A owners should know about the Unofficial LS3/5a Support Site. Follow the "Support" link to find some suggestions of possible sources of spare parts. And it's worth joining the Groups.io mailing list and asking for help and support there - you'll have access to many helpful and knowledgeable experts.

For help with the Celestion HF1300, Spendor might be able to help as they used this unit in the BC-1s and other models, although I'd imagine that any stocks will be scarce by now.

Harbeth purchased some of the remains from Rogers when they were liquidated, and they sometimes have trade-in stocks. It might be worth dropping them an email...

Wilmslow Audio have a good reputation for suggesting suitable modern equivalent drive units. For example, I was recently forwarded a copy of an e-mail from them, suggesting that a SEAS P21REX has been successfully used as a replacement in Studio 1As. OK, they won't sound completely identical to the originals, but many people would prefer that to a loudspeaker that don't work at all!

It's important to realise that that there are many, many variables and parameters involved with drive units, and it's basically impossible to find a direct "equivalent" from the available palette of modern drivers. Whatever you do, installing a modern drive unit will involve some compromise. Assuming you can't find a second-hand "donor" speaker (and have the speaker calibrated), rebuilding is just about the only way to maintain the exact performance of the original design. At a price...

Drive unit rebuilders

Dave Smith of DK Loudspeakers can rebuild drive units. A while back I was told that he had retired, but was subsequently told that this is actually not the case, and he is actively working at the moment. But that was about 10 years ago, so if anyone has any updates about Dave's current status, I'd love to hear from you.

From feedback I've heard, Dave has quite a backlog and can take many months to do a repair - also he can be hard to contact as he apparently diverts his phone (01708 447344) to voicemail when he's working.

Wembley Loudspeaker have a good reputation for drive unit repair for a reasonable price and have a very quick turnaround.

Another drive unit repairer that I've been told about is Recone Lab. Here's what Ian Read told me:

FYI - I've just had a defunct Studio 1 bass unit repaired by the 'Recone Lab' - one of the Richard Allan businesses (http://www.richardallanaudio.com/). The coil was burnt out so a fairly major rebuild needed, which eventually cost me just around £100 (including delivery there and back).

I thought you might want to add them to your known repairers. Health warning though - it took them 3 months(!) to do the repair, including over a month to even look at the unit. So not for the impatient ... I guess they've probably got more work than they can handle, as loudspeaker repairers in the UK can probably be counted on the fingers of one hand.

I've just (March 2021) checked the link, and found that it does not work. The current link is https://www.ratechnology.co.uk/ and here is a direct link to Recone Labs. At the time of writing, they are not accepting new work.

The LS5/8 and LS5/9 Audax tweeter

The Audax tweeter used in the LS5/8 and LS5/9 used to be widely available from Maplin and other sources until Audax pulled out of the DIY market. But they are available again. About 10 years ago, Nicolas Delatte sent me the following:

I just wanted to say you that their Audax tweeter is now available in France as TWO34XO at Sylvain Houlbert's Site: http://www.reparationhaut-parleur.com

Since then, it has become easier to find in the UK as Falcon Acoustics stock it.

Having said that, I would offer the following caution: I've recently learnt that this unit was available in at least two different versions with different sensitivities, and that the driver has changed over the years. Most surviving examples originally fitted to BBC loudspeakers have a large (4dB plus) spike at 11kHz or thereabouts, and the current version still has this, but at a higher frequency (more like 15kHz) and at a larger amplitude. I will post more detail once I've done a bit more research of my own.

Bass driver faults

Before you panic, consider that two of the most common bass driver faults are easily cured.

  1. The suspension of bass drivers can sag with age, which causes the voicecoil to rub against the magnet assembly, causing audible distortion. The cure is to simply rotate the drive unit through 180 degrees - this will fix most instances of this problem almost instantly, although it might take a few days in some instances. If you suspect this might be a problem, you can test for it without even taking your speakers apart - simply turn the cabinet up-side down! At the risk of stating the obvious, do make sure you protect the top surface of the cabinet.
  2. Occasionally, the glue securing the dust cap or suspension surround can come undone with age, which will cause buzzing noises. Because certain types of glue may attack the plastic or rubber materials used, I won't make any specific recommendations - you must do your own research and act at your own risk!

Caution - replacement drive units

Rogers hand-made most of their bass drivers and used commercially available units for midrange/treble duties. But be aware when buying second-hand spares that Rogers specified specially selected or modified versions of commercially available drive units. For example, the Celestion HF1300 was available in several different versions, and it's important to find the correct one when sourcing a replacement. I know for sure that Spendor used to measure them and grade them according to sensitivity, rejecting plenty in the process, and I wouldn't be at all surprised if Rogers did the same - certainly the LS3/6 was very fussy in this regard. Many years back, I had a loan pair of BC1s that sounded extremely odd in the midrange, and I'd put money on them having the wrong HF1300s fitted.

This was particularly the case for both the KEF drive units found in LS3/5A, especially the B110. I've recently added some information about this on the LS3/5A page, but it's worth seeking further information on the LS3/5a and Spendor Groups.io mailing lists.

AM8/16 repairs

Repairing the modified Quad 405 that power the LS5/8 should be reasonably straightforward for an experienced engineer. The BBC crossover PCB is pretty reliable, and problems tend to be restricted to the Quad amplifier boards. The Quad is a quirky design in many regards, and is rather more dependent on the electrolytic capacitors being in good condition than most conventional amplifiers. So, more so than many others, the Quad 405 does change the way it sounds as it ages. There is plenty of information about them already out there, so all I'll add is a caution to avoid some of the modifications - while many of these are potentially useful, they might change the specification of the system, and then it's no longer an AM8/16.

If getting them restored, make sure the engineer has access to the full BBC testing procedure so that they can be calibrated after repair. Unfortunately, this data is hard to come by, and isn't in the public domain.

In the past, I've been known to restore these, and as I do have the full BBC documentation I can test them thoroughly as part of the overhaul, and I can also audition them to ensure they are working properly. Please note that I find it really difficult to take on this sort of work at the moment, and if I do decide to take them on, there will be a really long wait to get them back. Believe it or not, I've had a pair sat here for 4 years! Fortunately, the owner is relatively local, and has my loan pair, which is why he's pretty laid back about it.

The most frequently-asked question about LS5/8s

To save time dealing with emails, I want to answer the question that ends up in my inbox most often:

Q: I have bought a pair of LS5/8s without amplifiers. What can I do?

Well, I guess it's too late to suggest that you read my LS5/8 page (if only the first few paragraphs) before bidding/offering/buying. Essentially, LS5/8s without the dedicated amplifiers are almost useless!

So what to do? These are the options:

  1. Obtain a pair of BBC AM8/16s. These are the modified Quad 405s which contain the BBC-designed low-level crossovers. By the way, BBC-modified Quad 303s are not compatible - these are AM8/15s that are meant for LS3/7s.
  2. Build a pair of AM8/16s by converting a pair of identical Quad 405s (preferably the later versions). You might have seen how I did this on this page.
  3. Obtain circuit details of the high-level crossover circuit that Rogers designed into the cabinet (see "PM510" on the Brochures page).
  4. Obtain a commercially available crossover unit, and two power amplifiers.
  5. Dump them on eBay!

Of these options, only the first two will result in a true BBC LS5/8 system. But unfortunately, the AM8/16 amplifiers are rare because the BBC tended to hang on to the amplifiers for use as spares. You'll appreciate that the amplifiers are easy to store, unlike the loudspeakers themselves... That said, you do occasionally see them for sale - I saw one on eBay a while back that fetched less than a standard Quad 405-II would normally get. Of course, it's only worth more to someone who needs one.

Take it from me, option 2 is a lot of hassle, not to mention expense. Of course, you'll need a genuine unit from which to clone the BBC-designed PCB, or at least some schematic diagrams of the crossover. These are hard to come by (and no, please don't ask me!).

While option 3 seems more plausible, the high-level crossover is even harder to find. I've never seen one. If I ever get a schematic, then I'll post it on the site assuming I can get permission. But while this option will get the speakers playing music, you won't have BBC LS5/8s - you'll have PM510s. If this bothers you, don't bid!

Option 4 is even worse in this respect. While you might be able to get the right crossover frequency, the "generic" crossover probably won't let you build in the additional equalisation that the BBC crossover circuit has. So while you might end up with a reasonable active system, it won't be an LS5/8.

Option 5 isn't as silly as it sounds! But you'll need to hope that prospective buyers don't Google "LS5/8" before bidding...

There are plenty of variations on the basic question - here's an extract from an older email:

I read your article on the LS5/8 and wanted to ask you is it worth my while to buy a pair of 405's and have them bridged with a compatible crossover. Or even go down the Chord route. What would you suggest. You mention in your article that you would like to do something entirely different with them instead of the 405 route. Could you include in your reply how much, within reason, the different options would cost, thank you.

First, the Quad's aren't "bridged". To be clear, bridging is a way of connecting two amplifier outputs to one loudspeaker to achieve a larger power output. In the LS5/8, the two amplifier outputs are connected to the individual voicecoils of the woofer and tweeter respectively.

The key phrase here is "compatible crossover". While there might well be some latitude with the exact power amplifiers you choose, you must have the BBC crossover PCB. Look at the pictures of the Chord LS5/8 - you'll see the same PCB that was fitted to the Quads.

Finally, I can't comment about cost. I'm not a dealer, and have no better idea than you about how much Quad or Chord amplifiers cost second-hand. Plus, the BBC crossover PCB is impossible to price. That's if you can find one. Reflecting on this question now, it does come across as rather demanding - I get a lot like this though! It seems that some folk think I'm a commercial enterprise - this really is not the case.

Sorry if this isn't what you want to hear. But please, do your research before buying!