Biwire Cables for Vandersteen 2CE Signatures

Side question. I see the terms true and external bi-wire and not sure what they really mean. If the amplifier has only one pair of output port per channel the wires pair(s), inside the sheath or outside, need to be twisted and single terminated on that end. Is there any other way?

Thanks for the explanation. I missed the tidbit about the (negative) interaction between the LF and HF pairs if they live within the same sheath. I expected good quality cables have adequate insulation to avoid that sort of "cross-talk". That said, one could extend that concern to having negative and positive cables inside a common sheath as being a poor practice. I have my 2Ci model bi-wired as well but my amplifier has two sets of output posts and using two separate sets of cables so I suppose mine is considered ""true" bi-wire.

It does make an audible difference for sure. Without the bi-wiring, to my ears the same content, particularly the mids, sounded more forward and noticeably disjointed from the rest of the music. As soon as I removed the jumpers and plugged the second set of cables everything sort of smoothed out.  I have a similar (bi-wire) set up with different amps on my Martin Logans and the difference was not anywhere as noticeable. Of course everything between the two systems are different including the listening room so it may not be apples to apples comparison. Just one more data point.