Speaker cable for Nad 7050 and KEF LS50

I've been using cheap speaker cables to connect my LS50s to my NAD D7050 and they sound great for my uneducated ears. I have never really invested in cables, but I was wondering if anyone can recommend/suggest any (not very expensive) cables that could make a difference.
Budget cables I have used in past with good results are canare 4s11, mogami, speltz anti cables, audioquest type 4, and now have morrow sp4. All but the morrow sp4's cost me less than $80. Of course this all depends on your budget and desired results but I found that all of the cables I mentioned to sound better the cheap wires. Other may disagree.
There is no silver bullet magic instant fix available. Your wish list for performance improvement (and system synergy) also has a threefold requirement: ICs, Speakers and power cables. Parsing out Attention to speaker cables blindly at the exclusion of the effect on the others wont get you what you want.

(1) System Synergy matters ..... Big time. {vis-a-vis among all your cables and also with rest of system}
(2) This is in constant tension with the truism that in this hobby that you get what you pay for .
(3) There is no escaping that, at a minimum, cables expenditures should form at least 10% of your total system outlay for quality performance experiences.
(4) Attempted short-cut deviations from these truisms invariably introduce performance comprises .
How long are the present speaker cables, and (if you know) what gauge are they?

-- Al
My friend has his LS50 Speakers connected to a Peachtree Audio integrated. I think the amp was around 1K and is class D. He is using Wireworld Solstice 7 speaker cables that cost him less than 200.00 new. I have heard his system many times and I have always been very impressed with the sound. It's very musical and very involving.
I believe that the cable is a QED Silver Anniversary XT. They are about 1.5 meter each. I am not sure about the gauge.

I understand that system synergy matters, but the fact is that I have the amp and the speakers. What I am trying to understand is if a new cable could make a significant difference to the sound.
08-02-14: Tvfreak
I believe that the cable is a QED Silver Anniversary XT. They are about 1.5 meter each. I am not sure about the gauge.
Despite its low price, based on its description your present cable seems to me to be worthy of respect. And FWIW I note that it has won several "What Hi-Fi?" cable product of the year awards.

It can be calculated from the indicated specs that it is equivalent to about 15 gauge, which is adequate for the relatively short length you are using. Inductance (which stands some chance of being an audibly significant parameter with your particular speakers, due to their low impedance in the upper treble region) and capacitance are both reasonably low.

The relatively low impedance of your speakers in the mid-bass region and throughout most of the treble region, as shown here, will tend to increase sensitivity to cable differences. But the relatively short length involved will work in the opposite direction, as nearly all speaker cable effects are proportional to length.

My suggestion is to first make sure that all of the contacts involved are both clean and tight. Consider buying a good contact cleaner, such as Caig DeoxIT Gold (formerly ProGold). Beyond that, if you want to try different speaker cables I suspect that you'll hear some differences, but I doubt they will be major, and they might not be for the better.

Finally, in addition to the particular makes and models that have already been suggested, this cable is another fairly inexpensive candidate to consider, which I have used with good results.

-- Al
The QED Silver Anniversary XT is an excellent budget cable and one that I have used for the past 8 or so years with a NAD 320BEE int amp, Outlaw RR2150 receiver, Prima Luna PL2 and PL5 tube amps, Rega Ara monitors, Omega Super T monitors, Opera Platea floor standers, and Ascend Acoustic Sierra One monitors.

I just recently upgraded to Clear Day Cables based on a recommendation from someone on Audiogon. Depending on the Clear Day product, the cables are several times more expensive than your QED. For me, that increase in price to Clear Day cables, resulted in a sound that is more musical, more focused, and still a touch warm, which I find very enjoyable. It is akin to a veil being lifted, especially for the lower frequencies.

So, the QED will serve you well and it did me. But I did find a more pleasing cable for more dollars.

Thanks all for the thoughtful replies. Based on your comments I believe I will keep my cables for the time being. As I said in my first question above my system is sounding great. Since I don't have much experience I was wondering if I had bought really bad cables and this could have been hurting the sound, but this not seem to be the case.
It's simply personal preference. QED is a quality cable, that some listeners like and some do not.
It appears that your cables are very respectable. My only comment is that QED is silver plated copper and you may find that a stranded copper conductor may have a warmer presentation. Or a single copper conductor such as Audioquest may be more to your liking.

You need to decide what kind of change, if any, you are looking for. Most will say that cables should be transparent, but in reality certain cables may colour your system in a desirable way.

And with cable selection, it's trial and error to find which is best for you.