i need 20 meter speaker wire, decent quality

Merrill;
I would not recommend using the standard 12 or 14 gauge solid core "house wire" as Morrow suggested as a speaker wire. It has heavy insulation all around, and sonically it is rather harsh and edgy. I have experimented with it for both AC cords and D.I.Y speaker cables with poor results. I tried the Anti-Cable solid core wires a few years ago, and was very impressed by some things it did in two different systems I had, but found it had tonality issues which I could not live with. I later tried a similar solid core cable (but cryo-treated) by JW Audio. It had none of the tonality issues that bothered me with the Anti-cables, and the detail and clarity was the best I have heard in my system at this point. My previous 6 foot pair of wires retailed at over $1,200, and I quickly sold them for half that amount. I was quite shocked that a $60 pair of cables could sound so much better in comparison. They do offer a 30 day trial, but you might want to see if they will still do so on such an unusual length. At $10 a foot, you will only be looking at a bit over $600 for a pair. That would be far more reasonable than a high quality set of 60+ foot interconnects!

Hey Shutterbug thanks, I will check out JW Audio.

btw $10 a foot needs to be doubled at Anti cable. And then when they do the labor of braiding and soldering spades, its over $1,800.00. for a shotgun bi-wire

I did not know you were were looking to bi-wire. I would guess, in that case, you would have to double the price for twice as much wire. I would not think that they would have to charge quite so much extra $ for 4 more spades on the speaker ends. I could understand a few extra dollars, but not four or five hundred dollars. If you have carpet on the floors where you are running them, it would be a good idea to raise the wires off the carpet a few inches to avoid any static interactions. A simple solution is to purchase some (in your case... MANY) inexpensive, round, 3 foot wooden dowel rods and cut them in half to make some simple "tripods" to keep them of the carpet. Home Depot sells approx. 3/8" diameter ones for very little money. You can even stain or gloss them to make them more attractive.

If the long speaker cable alternative is chosen, IMO there is a question which has not yet been raised that is essential to selection of an appropriate cable. And that is the impedance characteristics of your speakers at high frequencies.

I did a quick search but was unable to find an impedance curve for your speakers. Perhaps you can obtain one from MBL, or from a dealer or distributor, or by searching further with Google. If the impedance at upper treble frequencies does not rise substantially above its 4 ohm nominal value, then the inductance of the 20 meter length of cable becomes a significant issue. Relative to 4 ohms, the inductance of your present wires, and the inductance of 20 meters of Anti-Cable, and the inductance of ordinary heavy gauge wire, will all very likely be significant enough to perceptibly dull the extreme upper treble, and to cause perceptible sluggishness of sharp transients.

A major reason that the OCOS and Goertz cables that were suggested above tend to be good for long runs is that they have extremely low inductance. However, they also have extremely high capacitance per unit length, which would be factored up by the 20 meter length to levels that MIGHT be problematical for some amplifiers.

IMO, if you determine that the impedance of the speaker at upper treble frequencies is not considerably higher than its 4 ohm nominal rating, and if you settle on the long speaker cable approach, the Kimber 8TC that was recommended by Elizabeth would provide an excellent combination of low inductance, reasonable capacitance, and low resistance. The 12TC she also suggested is even better in those respects, but I suspect that it may be overkill.

I also agree with the comments that if your components provide balanced xlr interfaces, and assuming the sonic performance of those interfaces is good (which is not always the case), the long interconnect/short speaker cable alternative would be highly preferable. If you have to use unbalanced rca's, Bryon's suggestion of splitting the difference is also a good one, if feasible.

Regards,
-- Al

Al brings up good points. I use OCOS for a 5.5m run and have no problems with it. I have used Alpha Core MI-2 Veracity and feel it is one of the best values in audio. However, with solid state amps (and to be safe tube amps as well) it is best to get the zobel networks that can be provided with the cable. When I bought mine the zobel networks were free and were integrated with the cable.