Using different gauge wire for biwiring

Hi all, I have a 2 way speaker you can biwire. I was thinking using 12g wire for the tweeter and 10g wire for the mid/woofer, both wires will have same length. Is it better to keep the gauge the same for both? If so, should I use 12 or 10g for both? Thanks.
Using smaller gauge wire for the tweeter is not uncommon. I can think of a couple of manufacturers who build biwire cables that way. Dh labs Silver Sonic Q-10 uses 12 gauge for woofer and 14 gauge for tweeter.
You can use different gauge wire for highs and lows... thicker wire goes to the woofers.
Most internal speaker wiring is done that way. Also, some manufactured cables such as AZ Double Barrel use the same strategy (6awg and 10awg).
I've compared using smaller guage cables on top vs. using the same cable for top and bottom. The most phase correct result comes from using the same for the top and bottom.

Inside the speaker, the mfg may use different size wires for balancing the sound but, in the end, the speaker is designed to be hooked up with a single wire speaker cable and sound correct. If you slightly reduce the amount of energy to the top by using a smaller ga cable you are disrupting the balance of the speaker the way it was designed.

Good luck..
if your pigtailing the speakers bidding post? Then the distance from post to post is to short to be noticeable.
If you slightly reduce the amount of energy to the top by using a smaller ga cable you are disrupting the balance of the speaker the way it was designed.
Hifichic, I agree with the electrical theory but I question whether there would be an audible effect of the two different sizes because the current demand is typically lower to the high frequency drivers due to their higher sensitivity and lower resistance. I think the penalty could possibly be higher if the MF/HF and LF wires are the same gauge but the resistance of the LF wire prevented adequate current transfer to the generally lower sensitivity bass drivers, especially in the case of long runs. That said, most audiophile wire is likely oversized for the required current flow, and I am sure the 6awg of AZ's Double Barrel is probably not needed....except for welding.
I personally would not use different gauge wire on a 2 way because you are making the wire change in a critical area of the music. I have found some speakers that offer separate posts for bi-wiring actually sound more coherent with single wire.

If the speaker is a 3 way and the woofer is crossed very low I don't see any harm in a different gauge wire to the woofer.
The ideal is to use identical wire. Barring that, if you only have the two different sizes on hand, surely you an use them to bi-wire. For many years prior to buying entire sets of cables to compare I would swap around different cables on the Mid/Treb and Woofer terminals. It helped to teach me the importance of distinguishing between different cables and their effects.

If you have a good rig and good ears it will be likely that you will immediately notice a difference in the sound if you swap the two cables. You may be very surprised at it. The largest reason for this is the difference in total gauge.

There is no predicting which you will prefer; you may end up liking the sound of improved mid/treble with the larger cable on top, versus the cleaner, fuller bass with the larger cable on the bottom.

Your choice. But, immediately you'll realize that with both sets of terminals having the larger cable you'd have the better mids/highs AND the better bass. You would have just proven to yourself the importance of running the same cable to achieve superior results. :)
05-03-10: Douglas_schroeder
The ideal is to use identical wire.

Why would that be the case? Wiring in just about any application is sized to the current demand. My experience is with the DH Labs cable which is a 14g and 12g combination and it has worked admirably with two very different speaker and amp combinations.
It depends how cable is built. From manufacturer's point of view skin effect in copper starts at 20kHz at about gauge 18. Using stranded wire is not the best thing since current jumps constantly from strand to strand (to get on the outside) going thru impurities of the surface (oxides). Using isolated strands solves the problem by increasing surface area but strands are still in common magnetic field of each other (that adds). Placing strands on oversize tubes (Audioquest, Acoustic Zen) or making flat cables puts each strand in magnetic field of neighboring wires only (mostly).

I don't know if skin effect is audible but I know that cable manufacturers believe it is and come-up with such exotic schemes. My Acoustic Zen Satori Shotgun uses same gauges for woofer and the tweeter (many isolated strands of solid wire about 22ga on a big hollow tube plus one stranded wire with about 10 strands of very thin wire) but it is recommended mostly for tweeter+midrange on one and woofer on the other (or 4 way systems). For two way systems they recommend another cable where tweeter and mid/woofer have different gauges - Hologram Bi-wire.

Some info is available at Audioqest website:

and Acoutic Zen website:

I don't question their findings since I've never designed any cable.
Rhljazz, quite simply, it sounds better.
Anyone like the Anticable in biwire?
I went thru a rather exhausting speaker cable search going from name brand cabling to DIY and all manner of mix and matching in guage and composition.

For example I used a combo of solid core copper and solid silver of different guages, one for the top one for the bottom.
To make a long story short, some music seemed to favour one type of set up,and sometimes the thicker guage on the top end made for a more full midrange type of sound.
At other times, this wasn't a good thing.
As far as jumpers go, the stock ones weren't very good, and no jumper set up was as good as two separate runs of wire.
I am in agreement with keeping both runs exactly the same.

In my case the system sounds more coherent.
I agree with Lacee. Same cable for tweets and woofs, and same lenghts as well.