does high end system need expensive speaker cable

Like Timo, I agree that more expensive cables does NOT imply better sonics &
Like Inna, I agree that right now you don't know what your system is capable of. Just reading the list of components tells me that you *should* be able to create a grand sonic experience that comes closer to reality than many, many other systems out there. Do you feel that you have an awesome sonic experience every time you sit & listen?? If not, then you are missing something: your components are not synergistically matched, you might be skimping on speaker wires, you might have the wrong combination of interconnects & speaker cables, your room might need treatment, you might need better isolation, etc, etc. Since you make no mention of your setup environment, people cannot guide you: whether you need better speaker cables or something else.

What high quality speaker cables bring to the table are:
* ultra low resistance.
* good/superlative insulation material (aero-PE, teflon) such that the capacitance/ft. is minimized.
* very low inductance.

Having high resistance in the cable has an adverse effect on the bass quality - it becomes flabby, loses its punch & it'll overstay its welcome in the room.
High capacitance *might* cause a lesser amp to oscillate (i.e. become unstable) but I doubt that the FPB400 will be perturbed.
Having high inductance can cause high freq. roll-off & this roll-off can be disproportionate across the 10K-20KHz range i.e. it could be more in one area vs. another.

The above listed effects are not exhaustive & shows what *could* happen when some cable electrical parameters are on the excessive side. Note that most reasonably constructed cables already have very low R, C & L & so when comparing these electrical charac. one is comparing a few tenths or hundredths here & there - it's all RELATIVE. You might be asking if a few tenths or hundredths here & there makes a difference? My personal experience says that it most certainly does! However, YOU should listen to a few brand names & convince yourself. You'll find that cable insulation, litz or not, single strand or multi-strand, thick gauge vs. thin gauge will make a diff. albeit subtle. You'll have to draw the line by looking at your budget.

It is not always true that the more expensive the cable, the more merits it has w.r.t. the qualities listed above. However, most of the time, more expensive cables have much better quality of parts that leads to having better electrical characteristics than a cheaper cable.

Having said all this, electronics & cables is a synergistic match 8 or 9 times out of 10. Just 'cuz one has the best electrical charac. in a cable doesn't mean it'll have the best sound in YOUR system! The unfortunate truth, I'm afraid! You'll have to try various cables before you settle on one than does better than the Red Dawn. Then again, your audition might show that the Red Dawn is the best for your system. Tough for me to say.

So, there IS a jungle out there w.r.t. cables so start looking @ cables that others have used with Krell gear. I have seen Krell being used a lot with MIT cables. This might be a good place to start. I think that Transparent cables & MIT have the same origins & so Transparent cables will be another to look at.
FWIW. IMHO.

I would agree with the majority of opinions above that speaker cables have a significant impact on the sound of any system, and also that the cost of the cable does not always correlate to the sonic performance of the cable.

I have done some experimenting along the lines of what Newbee describes above, using both stranded and solid core wire of differing sizes, and even some different conductor material. I also tried using each cable type in both a single wire run, and a 2 cable bi-wire (as opposed to an internal bi-wire with one cable).

With each change in cable type, I was able to hear meaningful changes, and with all but a couple of the cable types, I was able to detect a subjective improvement using bi-wire vs. single wire. To me, this experience validated the idea that all speaker cables have an impact on the system sound, some more than others. When all was said and done, I preferred the set-up that I had started with, which was a double bi-wire run of mid-grade Audioquest speaker cable (Crystal). Unfortunately, or maybe fortunately, depending on how you look at it, my budget does not allow for me to compare true reference cables with my current configuration, but I strongly suspect that moving up the food chain would yield some sonic benefits.

Certainly there are many different theories/ideas regarding which design characteristics are most important for a particular type of cable, whether it is an interconnect, speaker cable, or power cable. Unfortunately, many manufacturers of high end cables don't disclose much information about their designs, so it can be difficult to know what you might be getting ahead of time. If an equipment manufacturer is not willing share with their potential customers their design priorities and product features that make their product superior, I usually assume that they have no design priorities or unique product features, and that they are simply trying to sell mediocre crap to un-informed buyers, sometimes at ridiculous prices.

Bottom Line (Since your original question dealt with the cost of speaker cables): Selling price has nothing to do with manufacturing cost or quality. Any product, whether it's a speaker cable or coffee maker, is worth exactly what you can get someone to pay you for it. This makes it particularly difficult to compare cables in the same price range from different manufacturers, because one might be running on thin margins, trying to build their market share, and the other might be sitting on a very small share, but pulling down 80% Gross Margin. In a high volume marketplace, the market forces will eventually "shake out" the scammers that are not providing good value for the dollar. In a niche market like high end audio gear, especially in any type of cables, you will not always get what you pay for.

My recommendation would be to audition some higher end cables from Nordost (to compare directly to what you are familiar with), as well as some upper-middle level cables from some other companies that you consider reputable, and decide what sounds best to you. If you find another cable that you really prefer to the others, try auditioning a couple notches up in their product line to see if you get continued improvement. For instance, maybe a cable with the same construction techniques, but silver conductors instead of copper, etc.. Eventually, you will get to a point where you are satisfied with the sound and you no longer hear a difference between similar models, or you will have reached the top of the product line, and have no more room to upgrade.

On the other hand, if you are satisfied with the sound you have today, it may be best to leave well enough alone.

Sorry to be so long winded,
Mike

He snorted?

I thank everyone thus far for their input. I agree that expensive does not necessarily mean better or higher quality. I did not articulate well when I made my posting. I wanted to get input on whether going from a good to a great speaker cable make any difference in a high end system. It seems that most of the responses have been yes but that each system responds better to particular cables and that you need to test it out.

Michael

By the way,

I also forgot to mention that the system sounds great. I upgraded from Wilson Sophias Speakers and a Krell integrated amp and the difference is significant. It just that I have the bug of pushing the system to its capabilities and was curious if it could be even better.