Huh, I can’t find reference where Cardas uses beryllium copper. Post a link if you know where that’s stated.
Beryllium copper is actually not that bad of a material to use as a conductor. Both Beryllium copper and phosphor bronze are typically used in situations where you need high spring strength (such as IEC connectors). The male plugs don’t need "spring strength" since they are just sliding into a socket (and not squeezing something together). Yes, pure copper is better, but it is harder to devise a female type socket with pure copper because it’s so soft. Furutech has been able to do this with its more expensive connectors. However, Furutech still uses both beryllium copper and phosphor bronze it its high end carbon fiber XLR connectors. If you look at the Furutech GTX pure copper outlets, you’ll see that they had to implement a steel spring to hold the contacts together.
My bigger concern with Cardas is any item that introduces silver as a conductor element. Silver has it’s own sonic character and will tend to push the mids/highs and could be lean on bass. It can sound artificial to me as well. I’ve experienced this when just putting in some silver plated fuse clips -- the sound went too much towards that artificial character. Also putting in a silver Hi-Fi Tuning fuse pushed it too far. This is my own preference in sonic signature, others may have different opinions.
