Enjoy your sysyem (and I mean that). I already have a 252/300 and love it, and I have no thoughts to change. I bought my 252/SCDR used, and my 300DR new (but for well less than the $14k retail).
My experience listening to my music doesn’t match yours. I never think of it as listening to Naim. Just listening to music. Each to their own I suppose.
Designacable dot com make custom REL “bassline blue” versions of their own VanDamme cables. Which can be connected at the speaker ends and are a quarter of the REL supplied cables. I just took delivery of a pair and they are beautifully made and the cable strands labeled. The cable actually feels better than REL cable.
No difference that I can make out. It’s a sub and I’ve dialled it down to just to augment the main speakers and it works. It’s not like its a NAC A5 versus Phantom. It’s a fraction of the REL price and it’s better made. I’ve got just 1.5meters from the speakers, and I don’t think you can call it at at just £80 it’s a punt.
One point with splitting the sheath is you end up with unsightly (to me) red and yellow wires visible. I bought some cheap black heatshrink cable covering from Mr Bezos to remedy that aesthetic issue.
That was for the single kitchen sub. In the living room I’m running 2 x T5i’s and highly recommend adding a second sub.
My dealer is making me some new cables using Audioquest Type 4. As some say, little need to spend much on sub cables but I thought WTH … curious to see/hear the difference esp as the subs are only used for music and are barely dialled in.
Heatshrink gets stiff when heated up. Better use braided nylon sleeving. Get the fancy one with gold or coloured stripes and you can pass it off as some expensive fancy interconnects.
Otherwise, just braid it like kimber kable with the three cores.