Which interconnect cable to upgrade first

Thanks. Right now i’m using the same brand/model cables for both links. They are Kimber Kable Hero’s. They are actually not bad for it’s price. i was considering going up the chain to the Select or Carbon line, or possibly another brand like Cardas. i’m hoping to improve the soundstage and warm up the sound a tiny bit.

Anyone had made similar upgrade before? would like your opinions on these cables if you do.

Thanks.

IMO both at the same time. Getting a new one, while still keeping the old one in the chain will likely not reveal much on the new cable. Just my two cents

I would do streamer first, then preamp. 

I upgraded my interconnects starting the source to preamp and then, the preamp to amp.  My rationale was minimize signal loss as close to the source as possible.

I upgraded to Kimber Kable  - Kimber sells trade-in and demos on eBay and are easy to deal with.

What improvements and sound characteristics are you looking for?