Best Budget RCA cables

If the spearitsound.com doesn't work out, you could look at Blue Jeans Cables.  They have pretty good options for under $50. 

Another option is to look at the Pangea or Audioquest cables at Audio Advisor.  They are both solid-core, which is much better in my opinion.

Ah, in response to your question, I would say that there would be a definite difference.  The Kabeldirekt may look very nice and even use OFC oxygen free copper, but they are likely using a very thin stranded conductor.

The Kimber cables have their own sound and it may be a nice configuration.  The Hero uses their vari-strand (putting about 7 strands of different gauges in a grouping).

I have always been a fan of solid-core cables (Pangea / Audioquest).  The sound is usually stronger and more solid sounding (no pun intended) than a stranded conductor.

Probably any of these cables would be an upgrade. 

@213runnin - I don't necessary agree that all interconnects in a system need to be solid core.  Granted, that would be the best solution, but even just having one solid core is better than nothing.  I would recommend this at the last point before the amplifier to "drive" the final sonic signature of cable charge/discharge characteristics.

Another comment.  Some of these interconnects use a much larger 18awg solid-core conductor (such as Signal Cable or Beldon 1694 from Blue Jean).  I have done a lot of R&D with solid core and have found that when conductors are larger than 20awg, then you start losing high frequency detail and clarity.  The larger-core conductors would be very good for a subwoofer cable as the larger solid-core awg will convey much more power in bass notes.  However, it's a fine line.  I found 20awg to be the best all around.  With 22awg and smaller, it will still work, but you start losing bass/midbass impact.

@leemaze - I don't know if there is a solid-core 20awg RCA cable.  Best I can tell, the Audioquest cables are all 22awg solid-core.  I have not done a lot of research, but there could be some cables.  For example, the Audio Sensibiilty Signature cables use a combination of 20/22/24 awg solid-core silver, but you are looking at $600 plus for an interconnect.

All my testing has been done from both interconnect and power cables I have built myself.  I have a power cord that uses 6 x 22awg conductors for each leg (making a 14.5 awg cable).  I also have another power cord that uses 3 x 20awg conductors for each leg (15.5 awg power cord).  Even though the 3x20awg cord has 20% less metal conductor, the bass power and slam is so much more.  On the other hand, the 6x22awg power cord has extraordinary amounts of detail and clarity in the mids and highs.  However, it is rather thin because there isn't much bass power.

The Audioquest power cords appear to use 19awg conductors for hot and 21awg for neutral/ground, which is a great balance between low and high detail. 

The Audioquest speaker cable also uses multiple gages.  The rocket 44 uses 17/18/20/21 awg conductors for difference ranges of frequency.

I have used the standard 12awg OFC stranded speaker wire for the longest time.  I recently upgraded to a Neotech NES-3002, which is 9awg that uses all 22awg solid-core conductors.  It is amazing, but I suppose the Audioquest with larger conductors can be very powerful in bass as well.

@lemaze - this is way over your budget, but Music Direct is selling the Audioquest Kind Cobra cables at 40-60% off retail:

https://www.musicdirect.com/Search/specials/Closeout?specials=Closeout&category=Cables&brand=Audioquest&sort=sitePrice%7CASC&page=1&pagesize=24&c1=tab-products&c2=grid

The King Cobra has their version of 21awg solid-core OCC copper conductors in a foam PE insulation.  Silver plated RCA connectors.