I messaged the seller, turns out they are LS55's. A quick google gives some positive stuff. But....from What HiFi forum> The OP was asking about a muffled sound.
Re: rogers muffled speakers...
Hello. I used to work at Rogers right around the time those speakers were being made. They may even have my signature on the back They were assembled at the plant in Mitcham in Surrey.
Sadly they are a part of Roger's 'death throes' range and are cheaply manufactured. They are hand built, but the cabinets are chip board and the woofers are all pre assembled. IIRC they have the clear drivers. They only retailed for about 200 pounds and the plastic frames on the front were whacked in with a rubber mallet. hehe, memories !
OK, now for the bad news. The crossover networks in those speakers are chinese made, the cables on the crossovers (green and red I would bet cash on it) were soldered in by us. It was a way to get around the Made in England sticker on the back of the cabinet.
All of the drivers in those speakers were made by Vifa, who are a spanish company. IIRC those drivers were about 3 pounds each for us to buy. You will not find them as in 1999 the company closed it's doors in the UK forever, the company was bought by the japanese and was taken lock stock and barrel to the far east. www.rogershifi.com
Please do not try and use cheap piezo type tweeters in there, you will damage your amplifier. Also please note there is a cut out in the tweeter hole when you remove it, 3 screws if memory serves and you will NEVER find another tweeter that fits the holes and has aligning screws. You may get one in there, but the screwholes will be a country mile off (this was intentionally done by our R&D team to stop people putting in non rogers replacements. A large lump of our profit came from replacement drivers.
I would buy some dome tweeters with a specification *as close* as you can get. These won't be cheap (probably 15-20 pounds each retail) and fit them carefully. However, before doing so test the tweeters as you may find the problem is with the cross over networks (if it is wave them goodbye and DO NOT try and fit new crossovers in there, you will damage your amplifier). To test the tweeters simply get a 1.5v AAA battery and connect wires onto the tweeter terminals and then connect those to the positive and negative ends of the battery (doesnt matter which way around) listen for a scratchy rustling sound. If you get that sound your tweeters are working and it is the crossovers.
HTH, good luck.