speaker cable recommendations for Joseph audio perspectives2

I have a pair of Joseph Audio Perspectives2 floor standing speakers. I have yet to pick a pair of 8ft speaker cables for it. My budget is around 2k usd, 3k usd max for a used pair. My amp is wells audio innamorata signature. The rest of my set up can be found in my signature.

I cannot use speaker cables that have boxes (like Transparent, MIT, etc) due to space constraint. Now I am using a cheap pair of blue jeans 10 speaker cables. I have not tried many speaker cables before, so when I borrow my friend's taralabs 0.8 speaker cables the other day, I was blown away how it improves my system's overall performance. So I decided that I need a speaker cable upgrade.  Thanks for any suggestions.

Nice speakers and amp!  Joseph Audio has a long-standing relationship with Cardas and uses their wire internally in their speakers, so they’d obviously be worth exploring (although I’ve not heard them myself except at JA show demos).

That said, I’m a huge JA fan and believe Acoustic Zen cables offer strengths that would synergize very well with your speakers.  You could get a double-barrel shotgun pair of AZ cables new for $2,248 that’d likely sound fantastic with your Perspectives.  I’ve been using them for years, and they excel at sounding very neutral and natural with very good tonality and excellent 3D soundstage.  Hope this helps, and best of luck in your search. 
A friend of mine, after trying a number of different brands in your price range, ended up using Duelund DCA 16GA wire, unterminated for his JA Perspective2 speakers (around $7/meter).
I highly recommend Silversmith Audio Fidelium. I am using on a Pass Labs INT-250 amp and GoldenEar Triton Reference Speakers. https://silversmithaudio.com/fidelium-cables/
Another vote for the Silversmith Audio Fidelium Speaker Cables.
30 day return policy.
My bet is that you won't return them......
I use Cardas with my JA Profiles. They work well and are far better than the one-off pair of cables I was using. Any chance you could work out some loaners from an audio shop? If you are intent on purchasing they may be willing to offer you a couple pairs to try out. It's really best to audition as the interface between electronics and transducers is rather critical.
@tomogolfs Thanks! Which model of Cardas are you using? I heard that the clear and clear beyond are good, but I don't like the blue color of them. Will the golden reference do a good job? 
Audience AU24 SX. Set 'em and forget 'em, as they say. They do nothing wrong and everything right. Neal
yuhengdu_tiger  First, congrats on purchasing your glorious Perspective 2's. I'm envious. I am using the blue Cardas Clear cables you mention. I love them and they work well with my Bel Canto amp and other Cardas interconnects. I suspect, though you'd probably do well to step up from the Clears to get the most from your sound system. Does the shop where you bought the Perspectives have suggestions, loaner cables? Some shops even have demo cables they are often willing to sell at a great reduction. Some shops even take in cables that they sold when someone wants to upgrade. Again you can get a great bargain. I'm an old(er) audiophile who recalls the 10 cents a foot zip cord in my first sound system (circa 1975). I recall when the gauge increased and the price went up to a buck a foot. I thought that was outrageous except they did reveal more musical detail in my set-up. Now it's $100 to $500/foot. Sigh. Still, it's the same with golf equipment (my other love). Once upon a time you could buy a top grade driver for under a $100 (and keep it for years and years). Now they're $500 and you'd best upgrade every third year or your giving up a lot to the field. Anyway, good luck.
I highly recommend that you audition Cerious Technologies Graphene matrix cables. Bob Grost offers a trial period. I'd also recommend the
 Silversmith. I haven't heard them but at some point I'll check them out.