Hi Norman,
Welcome to Beoworld! I am pleased to confirm that yes, you CAN use these Beolab speakers with a Loewe TV (or indeed with any non-B&O TV). As most Loewe TVs have surround sound decoders built in, you wouldn't need a separate AV receiver, you just need the DAL adapter and Audiolink breakout adapter from Loewe to give you the pre-out sockets required for connecting the speakers.
As a quick note for future readers of this thread, Loewe and B&O are the only TV manufacturers who commonly fit surround sound decoders to their TVs, so for other brands of TV then you are quite correct that you would add an AV receiver with pre-out sockets in order to add the Beolab speakers. There are no issues with audio delays or signal levels, as these receivers are designed to work in this situation and the RCA audio pre-out sockets are correctly matched to B&O speakers.
However, please don't try to trigger the speakers using the 12 volt output of either the Loewe TV or an AV receiver. I have gone to great lengths investigating this option with TV and receiver manufacturers and every company that I spoke to said that this type of connection could cause problems (and in some cases would invalidate the receiver warranty). There are other ways to connect the speakers safely, as outlined below:
For TVs without a surround sound decoder fitted, I would suggest looking at the Pioneer SC-LX59, Denon AVR-X3300, Yamaha RX-A830 or RX-V775 AV processors/receivers, all of which have audio pre-out sockets for easy connection of Beolab speakers for a Dolby surround sound setup.
You can connect stereo Beolab speakers (eg. Beolabs 20, 6000, 8000, etc) to one of these processors using these cables (one set of cables is needed for each pair of speakers to be connected):-
link
If you have a Beolab 2 subwoofer, or a Beolab 7-x/Beolab 10 dedicated centre speakers, these each need a powered cable to generate the trigger signals that would normally be sent from a B&O television:-