Hi guys, I'm new to this forum. I have used NACA5 in a variety of rooms and with a variety of equipment, but mainly with a Rega Luna amp from the 1990's through Ruark Epilogue standmounts. I found tremendous clarity, separation and detail, but I've never found a situation with it that didn't lead to uneven bass response. Basically if there was a bass trap in the room the NACA5 cable found it. This has been the case with rooms large and small. I currently use QED XT40 (£10p/m) with my all-Rega system (RP8/Exact/Aria for vinyl, Elex-R amp, Apollo R CD and R3 speakers - soon to be replaced by RS5's). Everything that the Rega's are renowned for is all intact - communication, refinement, pace, rhythm, timing, separation, detail etc.... but with a far more even bass response.
I heard Rega's new RX3 speakers on demo (with all the other components the same as mine) in a well-known Rega/Naim chain who insist on NACA5 to demo everything and as soon as John Mayer went into the Apollo I thought oh, here we go... boooooom (+overhang), just ignore that and focus on everything else!
Having researched this a bit (cos I seem to be one of the few who doesn't swear by NACA5) it seems that Naim used to recommend 2x3.5m lengths of NACA5 with all their amps, and wouldn't necessarily honour a guarantee on an amp if a fault arose and other cable had been used. Something about inductance I believe, but also about squeezing every conceivable pound from the hi-fi lover I rather fancy! Whilst this may no longer be the case there is no doubt that NACA5 and Naim amps are fine tuned for each other. I haven't owned anything Naim apart from this cable - but I've demoed some amps. I put the Nait 5i (I think!) against a Rega Mira 3 back in 2006 and whilst there was a good deal of solidty and togetherness about the Naim, I didn't like the boom/tizz of it. I thought that would get tiring and stress out the neighbours too much! The Mira 3 felt more neutral - perhaps bass light - and this has proven to be the case after a number of system upgrades - but it does agility and atmosphere in spades. I could "see" Jamie Cullum running around and tapping on the piano wood during Fascinating Rhythm and smell the incense during a couple of Kula Shaker tracks, experiences that were diminished on the Nait. So the cable did its job of revealing the differences between each amp - it seems very warts and all and I just found the warts and decided to go with a different option that minimises them!