I am contemplating a new design for speaker cable stand-offs. I am unable to find support, only opinions, about static electricity produced by carpet affecting AC current between amplifiers and speakers. Does it affect sound quality or does it endanger electronics used in speaker crossovers?
Beware the "audiophile" hi-fi market, there is a lot of very dubious product sold, often at crazy prices, to exploit and generally befuddle the innocent.
In this category, we might include items such as:
- speaker cables that claim to have almost magical properties, including but not limited to, directionality. The function of a speaker cable is to make a reliable connection of lowest possible resistance from amplifier to speaker. A few 100pF of capacitance and similarly low inductance is of little concern in any normal living room environment. A piece of heavy duty mains flex, available for a few cents/pence per metre is fine.
- equally, line level interconnects which are attributed similar magical properties.
- just about anything labelled as "cryogenically treated".
- ditto anything that mentions quantum effects for no good reason (and there really is no good reason in audio engineering).
- other odd things, like little wooden blocks for keeping cables off carpets.
I hope that helps.
EDIT : I guess some technical explanation might support the argument. So let's consider what happens when you walk around, wearing rubber soled shoes on a carpet, then touch (say) the metal radiator, resulting in a loud "crack" of static discharge.
What is going on here is that your body, which is more or less conductive, is very highly insulated from earth by the shoes (we are talking probably hundreds of megohms, maybe more). There is no current path from your body back to earth as you walk. In addition, the carpet and rubber are conspiring to build up an imbalance of charge between you an earth, because of friction. When you touch the radiator, your body is some significant voltage (I have no idea how much) away from the metal, which is very well connected to earth. You discharge very suddenly, possibly dropping your glass of expensive single malt and uttering a loud expletive in the process.
Now let's take the case of the speaker cable trailing across carpet. There are a number of key differences:
- The cable doesn't walk around. There is no significant friction. (It also doesn't drink whiskey or swear.)
- The cable has a rubber or plastic jacket, but the internal wires connect to the amplifier, which ought to be connected to earth by a fairly low impedance path. The wires are NOT isolated. There is really no possibility for significant charge to build up.
So we see where the idea comes from, but, as usual with this kind of thing, it lacks any form of foundation in reality. If there WERE a problem (there isn't) the logical thing would be to create a good low resistance path to earth - NOT to increase the isolation by using little wooden supports.
It's really a very silly myth designed to part the ignorant from their cash in an efficient manner.
For years I struggled with sound that was too bright. I have a medium quality tube amplifier and horn speakers. Accidentally I discovered that nicely separating interlinks from current cables and lifting my mainsblock and cables from the floor on small wooden stands made the sound smoother. Isolating the plugs of interlinks and speaker cable with a bit of foam tube also works. Actually, there's nothing better than grounding your amplifier and cd-player. Putting wraps from Entreq over your plugs also works the treat. It's expensive, but my ears are too sensitive for bad sound (hard hearing and tinnitus). Sceptics beware, hold your jokes and comments, because in my case shielding cables works. I'm a happy audiophile now.