Hi Dave,
Welcome to Beoworld and thanks for your purchase from my site! Speakerlink (eg. on Beomaster 5500 and Beocenter 9000) is an amplified output which is then reduced down again in the same way that my attenuated converters do. Powerlink (eg. on Beomaster 6500 and Beocenter 9500) is a low level signal taken before amplification, so this is theoretically higher quality when connecting active Beolab speakers (as the signal has not been amplified and then attenuated again). However, either option can high great sound when wired with good cabling.
Please don’t worry that Powerlink cables aren’t as thick as traditional passive speaker wires. As Beolab speakers have their own amplifiers built in, the Powerlink signals don’t need to carry the heavy currents that are required for passive speakers. This means that thinner cables can safely be used without losing signal quality, even over long distances (I suggest 20 metres as a sensible limit).
Also worth noting is that some systems (eg. Beomaster 5000, 5500, Beocenter 9000) have RCA pre-out sockets, which are also un-amplified and volume controlled, similar to Powerlink. These can be used to connect Beolab speakers, once the speakers are set to “Line” mode.
Finally, Beolab 4000 comes in two versions, mk.1 speakers have a separate RCA line input for use with a non-B&O system or early B&O system without Powerlink, whereas the mk.2 versions use their Powerlink sockets to connect when in Line mode. You can tell mk.1 speakers as they have a power button on the front of the speaker, while mk.2 speakers don’t have this. I can help with cables for either option!
Kind regards, Steve.
