Maybe since I managed to double post this I should amend my comments above to read I am "stupid and clueless" |
Capacitance is the capacity (get it?) of your wire to store electrical charge (i.e. the energy coming from your amp on its way to your speakers). If your speaker cable has lots of (i.e., high) capacitance, they will store energy as it enters the wire (when any loud passage occurs in the music) and dicharge it as soon as the level drops (when load pasage is over). This is bad for two reasons: 1. When your cable is fully charged, it tends to block (impede) signals trying to get trough. This can only muck-up the sound. 2. When music level drops, the stored up energy will discharge into your speaker creating a signal that wasn't on your CD (or whatever) creating "ghosting" (like a bad T.V. picture before cable T.V.). This will blur the sound and cause other unmusical havoc. Capacitance is caused by lots of things like thickness and shape of the wire and what the wire is covered with. Teflon is used in high-end designs because it doesn't like electricity and will store almost none (low capacitance). Enjoy our hobby! |
High capacitance usually rolls off the high frequencies, not the midrange -- plus, I didn't think the WW Gold Eclipse III was a high-capacitance design. Maybe something else is responsible for the reticent midrange; without more details, I couldn't say. Good luck, let us know if you track down the problem. One cheap way to see if it's the cables is to swap the WW cables for something different and see if the balances changes to your liking -- heck, some standard 14 or 16 gauge zip cord from the hardware store would tell you what you need to know. |
There are few errors in kkirkpa's post. Yes, it has to do with the storage of electrical charge. But the idea of storing energy during loud passages and releasing energy during soft passages is a little off base. The signal from the pre-amp is constantly charging and disharging this capacitance. The energy is stored and released at the same frequency as the electrical signal, i.e. if fed with a 1000 cycle signal, the cable is being charged and discharged at this rate. The preamp sees this capacitance as part of the total load it must drive. Loudness really has nothing to do with it. It turns out that the higher frequencies are more affected by this than the lower. The higher frequency currents flow more easily through the capacitance than the low frequencies, so as Plato points out, you have less high frequency energy reaching the speakers as the capacitance increases. Some very wide bandwidth amplifiers like Spectral recommend using high capacity interconnects from the preamp to limit the very high frequencies getting into the amp.
The construction of the cable does determine this capacitance. There are three factors. Size, distance, and dielectric. Larger wires with more surface area and putting the wires closer together will increase the capacitance. Changing the dielectric (the material separating the wires like the teflon mentioned above) will also affect it. Air has the lowest dielectric constant and will give the least amount of capacitance.
That being said, I doubt that this is your problem. I would suggest experimenting with speaker placement as a way to affect your center image and soundstage. Start by moving them close together and toed in until you get a clearly defined center image with limited soundstage. Then move them apart and toe them out to expand the soundstage until your center image gets too diffuse. Somewhere in between is where you want to be. There will be a sweet spot where you get both. Of course, this also affects the frequency balance. It takes a lot of time a patience to get it right, but nobody said this was going to be easy. |
I think Bruce1483 is correct on this issue - this sounds more like a speaker placement problem. I can assure you it is not the capacitance of the WW Gold Eclipse III cables - they are a low capacitance design. |
I have interconnects that will COMPLETELY change the soundstage and tonal balance due to their high capacitance design. Mids are slightly distant and sunken, highs are smoother with less splash, bass is slightly elevated which adds warmth, etc... These work fabulous for systems that are bright, hard or way too forward. As such, they can take a digital based SS system and turn it into something that is warm and musical. A few others have commented about this cable in the past. Like anything else though, the results are both system dependent and up to personal tastes. ANY interconnect that uses a foil shield is a high capacitance design. Sean
> |
Rzado - how do you come to the conclusion that the Wireworld are low capacitance? Here we have two "shield-type" braids separated by a very thin layer of teflon. Large surface, very close together - am I missing something? |
It's all relative. One farad is high capacitance, but not as high as ten farads and should be relatively inconsequential at audio frequencies. A few picofarads per foot is very low in comparison to either. If any decent audio cable really affects the tonal balance, it is probably more a matter of the electronics design; that is, circuit performance susceptible to minor load characteristic changes. I know this is not a popular position with all, but there...I sadi it. :) |
Please let me clear up one small item in my post above. I knew that a vacuum was a better dielectric than air, but assumed that no vacuum interconnects existed. I was wrong. I saw an ad last night in Stereophile for "the worlds first vacuum interconnect." Who would have imagined?
I also don't think that "ANY interconnect that uses a foil shield is a high capacitance design." If enough space is left between the center conductor and the shield, it can be low capacitance.
I was curious about the Wireworlds, so I went to their website, but they don't post the electrical specs of their cables.
I agree with Sean that cables can affect the tonal balance of a system and that it is system dependent. I based my speaker placement theory on the description from Ignatz that he had "a too deep soundstsage with diminished volume from the center image."
Ignatz, I have some very low capacitance single ended homebrew cables that I would be happy to let you try. Send your address to me and I'll mail them to you. Also, what length do you need? |
Thanks to everyone for your responses. I continue to be impressed by the amount of information available on this forum.I now think I have a general understanding of capacitance, which leads me to a further question. Wouldn't the effect of a high capacitance cable on sound have a lot to do with the output impedance of the preamp and the relationship between output impedance of the preamp and input impedance of the amp? Thinking of the pipe example wouldn't a preamp with a realtively low "push" coupled with an amp that has relatively high resistaqnce to that push exacerbate capacitance problems w/ a cable? |
Although I'll probably be trashed by other engineers, I think it all has to do with the speed of electrons.
Capacitance slows them down. (Remember EE-101: voltage can't chage instantaneously through a capacitor.) Ideally you to want them to move as close to the speed o' light as possible. I think this explains why silver conductors have a distinctive sound; ie, great transients & realism. |
Well this EE would like to point out that it's not the electrons that move through the cable at all - it's charge or electromagnetic flux. It is very similar to the way sound waves travel through the air. The air molecules do not move from the source to your ear they instead impart their momentum to the particle next them and so on and so on. The speed at which a charge moves through a cable is termed the propagation delay. Like sound, the speed of propagation changes depending on the material it is being propagated through. In a copper cable the speed of propagation is roughly 2/3 times the speed of light. - Dan |
Although I agree with most of the above, according to standard crossover design, any frequencies effected by the capacitance of the cable would be (1/RC). If the capicitance of your one meter interconnects is a only a few picofarads (as it shouldn't be any higher), then that multiplied by the few ohms of resistance in a given length of copper is going to be astronomically high (10^8 Hz). So why does capacitance have anything to do with this. Also, if capacitance effects speed of propogation, where're talking about ridiculously small differences in time, which would make it impossible to detect any differences in transients. I do agree that cables sound different, but they can only make very small changes. Make your components sound good together first, then tweak with cables. |
Once again. I appreciate the info. However two things to think about when talking about these issues. 1)the interconnects in question are silver 2) due to the cable construction which is strands (162 I think) wrapped around the exterior of a tube the lengths of the strands are a multiple of the 1.5m length of the interconnect. |
Just so I don't lose too much credibility (assuming I have any), my post should have read: "One farad is high capacitance, but not as high as ten farads . A few picofarads per foot is very low in comparison to either and should be relatively inconsequential at audio frequencies." Thank you Dan2112 for saving me that post. :) |
Bruce 1483,I have electraglide reference signature ic's and they are vacuum sealad and have been around for a while. |
