While searching for an inexpensive, home built, speaker cable that would give me improved performance on my system I discovered something that surprised me. By combining two different speaker cables in parallel I got not only the best characteristics of each cable but vastly improved imaging and instrument definition as well.
I tried quite a few different (and low cost) combinations of wires and cables looking for something that made a positive improvement over standard 2 wire speaker cable. My speakers can be bi-wired so I included several variations of bi-wiring in my experiments as well. I ended up with two cable types that showed promise but neither one got everything quite right by itself. You would naturally think I might try bi-wiring with both cables but previous experiments using two different wire types bi-wired did not give the desired results. So what about putting both wires in parallel to just one set of speaker terminals? At first I thought, no way, you can't get the best of both wires just by using them both together. But then why not just try it? I did and was blown away by the result. First I'll describe the wires I used and what each one did on its own and then I will describe the sound of the combined cables.
The first wire I'll call the high frequency cable because that is where it showed the best performance. I had some tubular tinned copper braid wire that was about 3/4" wide when flattened. (If I understand the dimensioning of the braid correctly, that would make it about 1/2" I.D. when in tubular form.) Therefore it should be similar to Belden 8669. I laid out two runs of this 3/4" wide braid side by side (see photographs). http://i447.photobucket.com/albums/qq199/ROVA_photos/_DSC1120.jpghttp://i447.photobucket.com/albums/qq199/ROVA_photos/_DSC1119.jpg
I reasoned that this configuration should provide low inductance without being high in capacitance (as would be the case if the runs were right on top of each other). This is similar to what Nordos does with their Valhalla cable; but of course they have other tricks as well as this one. Since I was just proto-typing this I used the simplest insulation I could. For each wire I laid the wire in the middle of 2" clear packing tape (laid out length wise along the wire). I then folded the edges of the tape over the wire to completely cover the braid. After finishing both wires I laid out another piece of 2" clear packing tape flat on a table. Then I placed each wire on this tape side by side. I then finished by covering the arrangement with a top layer of packing tape. At the ends I wrapped each wire separately with a few rounds of the same packing tape. I bunched up the braid into a tight bundle and placed that into a banana plug connector. Can you come up with a better insulation scheme? I'm sure you can. I don't expect the packing tape will provide a long term solution. This wire, used as a speaker lead by itself, provided very good high frequency performance. Transients were sharp and clear. The room ambient details were very good. Imaging was also generally good. The only problem with this wire was the lack of bass. I was surprised that the bass was so poor because the equivalent gauge of this wire is quite heavy. Perhaps it is the tinning on the wire that is causing the problem? The bass was so lacking that instruments and even voices lacked the fullness that would be provided by a balanced frequency response. The Belden wire is about $4.50 a foot, I already had this wire around so it cost me nothing. I'm sure you can find something cheaper. I suspect tubular braid is not required, so a flat braid should be fine.
The second wire I'll call the low frequency cable because this wire had very good low end performance but not as good of high frequency performance as the flat cable above. This is standard 2-wire, OFC, speaker wire, but of a heavy gauge (8 AWG). This was Audio Research 8 AWG OFC with a PVC jacket that I got for $1.00 a foot. This is not real high end stuff but one thing I did like was the distance between the two wires was small. I have seen a similar low cost speaker wire that had quite a bit of space between the conductors and this will tend to increase the inductance. This wire was pretty good all by itself. The bass and mid frequencies were very good. The high frequencies were good but not great. The imaging of this cable was not nearly as good as the flat braid. Neither were the room ambient details present.
Both cables were prepared like normal speaker wires with simple banana plugs on either end. The plugs were also low cost units at something like $5 for a set of 4 (flea market specials). Both cables were plugged into the speaker and the amplifier (also see photographs) placing the cables in parallel. http://i447.photobucket.com/albums/qq199/ROVA_photos/_DSC1118.jpghttp://i447.photobucket.com/albums/qq199/ROVA_photos/_DSC1115.jpghttp://i447.photobucket.com/albums/qq199/ROVA_photos/_DSC1116.jpg
I had hoped that putting the speaker leads in parallel would give me the high frequency response of the braid cable with the bass response of the 8 AWG cable without anything quirky happening. In real life things seldom work out so simply and so well. However, when I tried this it worked! Not only did I get the frequency response I wanted, with both ends filled out, but I got a bonus I never expected, the imaging was fantastic. The best (but perhaps not the most accurate) description of what I heard was holographic imagining.
The best way to explain the sound I had was to say the instruments and the voices now had there own distinctive space and that there was space in between instruments. Each voice and each instrument was distinctive and they did not interfere with each other. Each instrument or voice had a fullness or body to it (more 3D than 2D). With any other combination of speaker wires I had an issue balancing the voice and the instruments. Either I ended up a center stage voice that dominated the sound (making it difficult to hear the instruments details) or the off center instruments dominated making the voices hard to make out. With this new combination of speaker cables all voices and all instruments were clear and could co-exist, even at similar levels, without interfering with each other. The room ambient details were also superior with this combined cable. In fact with exceptional recordings the sound stage seemed like it could wrap right around your head. With many other cables when the instrument or voice on the sound stage comes from the speaker position you had the clear impression that the sound emanated from the speaker. With this new cable combination even when the sound came from the direction of the speaker the sound did not seem like it emanated from the speaker. Instead it appeared to come from a musical instrument that happened to be at the same position as the speaker. It's hard to describe but that is how I can best express it.
One thing unusual about my set up that you need to know just in case it makes a different, the low frequency wires were 10 feet long and the high frequency wires were 8 feet long. Was this on purpose? No. I only had enough braid on hand to make 8 foot leads. This left the leads hanging above the floor for one speaker. I could shorten the longer low frequency wires so they also hang the same but I hate to cut a wire, especially when experimenting. I reasoned that the sound wavelengths are so long that any difference in path length should be insignificant. However, in case this assumption is wrong, I thought everyone should know what I did.
The difference between the two pairs of cables in parallel and a single standard speaker wire pair was quite significant so I would recommend others try this. If it works the same for you as it did for me you won't be disappointed.
If you try this and it works well for you (even a variation of this idea) please post your results so others can learn from your experiences.