Fully refurbished with new tweeters and tested by Martin de Saulles, the acoustic and design engineer for Blueroom Loudspeakers Ltd., they are loaded with the later Peerless (Mk3) bass-mid drivers. The new tweeters give an improved 'knit' at crossover (see plot) and the 'rising response' was intentional to give them their signature 'brighter' sound, as in the Mk2.
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