I was looking around a forum yesterday and saw a thread where someone was looking for cables to smooth out his system. I have relatively frequently heard people want to use cables to tune their system. To a certain degree this is desirable, but I want to say a few words about this topic and hopefully keep people from going down a path that could end up costing more money and aggravation in the long run.
I agree with the general consensus that it's possible to make choices in cable and component selection to balance the character of the system, commonly called synergy... but this is more specifically about why you don't want to use cables to make large changes in the characteristic sound of a system, why you don't want smooth sounding cables in particular. Why it makes the most sense to choose the most neutral cables for your system that you can. And why good AC power distribution is so important.
First, the question of neutral must be addressed. I intend it to mean affecting the signal the least amount possible, adding the least amount of it's own character to the sound, letting the sonics of the source come through unaltered, sounding as realistic as possible in tone and body. It is a relative thing since we can't compare a cable to no cable. Well... it IS possible, but not practical... so it is a comparative judgement. But I think you get an idea of what I mean.
With a smooth cable, you are trading detail and resolution for warmth, which is distortion and causes coloration. So, you lose detail like reverb and note decay and add a distortion that is the same to everything you hear from your system. A touch of this can be good, and in less than perfect systems, which is almost all of them, desirable to some point. The better the system you have, the less warmth you want... why spend a lot of money on a good source only to have a cable "smooth out" all that glorious detail you paid so much for?
Having neutral cables and good power will also allow you to evaluate potential upgrades much more realistically. How can you really judge a component change with really warm or harsh cables, inferior power quality, power cords and connectors feeding your components? With neutral cables and good AC power delivery you will be able to get a more accurate picture of changes to your system. There's also much less liklihood of wanting to change cables to compensate for the introduction of a new component or tame harshness cause by poor AC power delivery. Good cables and good AC power distribution are the foundation of a good system and will allow you to make choices that will lead to real improvements because you will have less sonic issues like harshness, hardness, too much warmth or bloat related to poor AC power and cables.
The last issue related to this is warmth vs harshness. A good, very neutral reference level cable that is theoretically "perfect" costs a lot of cash. So if you're going to make a less than perfect cable to save money you must decide what the appropriate compromises are. The compromises generally make the cable or part you're looking at sound either more harsh or more warm. For example 4N silver has a thin, harsh sound that is easy to identify when used in cables. UPOCC silver is far more transparent and adds no harshness whatsoever, but costs several times the price... the other alternative to pricey UPOCC silver is using UPOCC copper. This makes for a warmer cable with less detail, but no harshness. This is a far better tradeoff because it complements the imperfections of a less expensive component while harsh 4N silver adds to the issues already present in a less expensive source/amp. Listening fatigue kills the joy of listening to music and it's the LAST thing you want! ZenWave errs on the side of warmth, and delivers as much detail and neutrality as possible for the price. I will give a no harshness guarantee.