Wiring speakers including in wall, wire gauge and phasing.

A little about speaker wiring and cables.

(Much ado about nothing?)

Not Really. First and foremost, wire selection can be very important.

Please note: this information is not a recommendation for you to do it yourself. We are not responsible for any damages incurred. We provide this information to allow you to make a wise choice. If in doubt, hire a suitably qualified professional.

General Considerations:

If you care about the sound quality at all, 22 gauge cable is not recommended. It can be used for very short runs, (less than 12 feet at 8 ohms, 6 feet for 4 ohm speakers) and is smaller for hiding, but due to resistance you will sacrifice some sound quality. I would recommend 16 gauge wire for most runs, unless you really want to get the best out of your speakers, in which case use 12 gauge or larger. For a very long (+48') run I would recommend larger than 16 gauge cable. I personally use a good audio quality 12 gauge cable myself, but you will pay more for cable this large. The advantages are better dynamics, and the amplifier can control your speakers better due to low resistance wire (this is called Damping Factor**, see the footnote). One downside can be that speaker selectors may not be made to take cable this large. In addition, if your speakers or amplifier will not take cable this large, you may need to consider that perhaps the system is not of high enough quality to show any benefit from this size of cable (except for very long runs). You may solder a smaller gauge pigtail on to the larger cable to allow for use with smaller size connectors. As always, let the price point of your speakers determine the cable. Don't put expensive cables on cheap speakers, and vice versa. Keep in mind that if installing in wall or plenum, or outdoors, the cable must be properly rated for the purpose (CL3 for in wall). BTW, don't try to use Romex instead of decent quality audio cable. Really, just say no. For so many reasons.

Maximum Speaker Wire Length

Wire Size	2 Ohm Load	4 Ohm Load	6 Ohm Load	8 Ohm Load
22 Awg	3 Feet	6 Feet	9 Feet	12 Feet
20 Awg	5 Feet	10 Feet	15 Feet	20 Feet
18 Awg	8 Feet	16 Feet	24 Feet	32 Feet
16 Awg	12 Feet	24 Feet	36 Feet	48 Feet
14 Awg	20 Feet	40 Feet	60 Feet	80 Feet
12 Awg	30 Feet	60 Feet	90 Feet	120 Feet
10 Awg	50 Feet	100 Feet	150 Feet	200 Feet

The above speaker wire chart is used to determine the recommended maximum run of each size cable. Using smaller cable than that recommended will not cause physical damage, but will result in degradation of sound quality. This is mostly due to the higher resistance of smaller cable. Cable that is too small does not just diminish volume, but can cause frequency response problems because of the impedance curve of most loudspeakers. It is also important to keep in mind that speakers rated at 8 ohms may dip much lower at specific frequencies, and if they do you may need to use wire larger than the chart shows to get the best performance from your speakers.

Phasing or Polarity

Polarity or Phasing of your speakers is very important. This means finding the wire with a stripe or writing on one side, and connecting that wire to either the + (red) or -(black) on the amplifier and the speaker. It does not matter whether the stripe on the wire connects to plus or minus, as long as it is the same at both ends, and on all speakers. I always connect the plus to the stripe, just to be consistent. If you get this wrong you will lose much of your bass response, and voices will float around instead of being centered when they should be.

Cable Quality

One common question is if fancy cable makes any difference. There are 2 main camps here, those who believe the subject is so much snake-oil, and those who swear by high end cables and accessories. Let me state that I am firmly in the camp of neither. I will start by saying use good judgement and common sense. I personally believe that I can hear some differences, depending on the quality of the associated system, length of cable run, etc. In other words, any hearable differences in cable will be more noticeable in a system with more resolution. It has been proven scientifically, beyond the shadow of a doubt, that cable differences affect the signal in various less or more harmful ways. The question is if those differences in the signal are hearable or not. Many listeners not selling cable claim to hear a difference, many say they can not. Remember that there are differences in people (concentration ability, audio memory, hearing ability, susceptibility to the placebo effect, etc) as well as differences in systems. I consider that anyone speaking in absolutes on this matter has not thought it out very well at all. Here are a couple of examples from both sides of the fence. (Be careful of double blind tests. I usually can pick holes in the logic behind most of these tests, and point out factors not considered.) One perfect example was an amplifier test (by a major audio magazine) that level matched the amps, did a double blind test, and asserted the amps sounded identical, so they recommended that everyone buy the cheaper amp. Here's the rub: Under their exact conditions, which were not normal listening conditions, the amps sounded the same. Consider this (unmentioned) idea: The cheaper amp had less power output than the other, and under normal listening conditions, say with loud rock music, inefficient or difficult to drive speakers would have pooped out before reaching satisfying listening levels, not to mention clipping and distorting from overdriving the amp (this magazine is now defunct). One problem with the double blind tests is, in order to be accurate, they have to control every factor in the universe that could affect the results, even unknown factors. The other is, in order to compare everything on an even playing field ( good intentions), they purposely diminish or nullify the differences (isn't this what we are looking for?), then triumphantly proclaim there are no differences. The example from above is level matching at a volume level that does not stress the more easily stressed amp.

The next example is of a speaker cable display by a major manufacturer. It compared a spool of cable it termed 'normal speaker cable' to a spool of it's own cable. It had a switch to switch between the spools of cable while listening to the speakers. There was clearly a hearable difference, even to skeptics. The punchline (?) is that the 'normal speaker cable' was a smaller gauge than the major manufacturer's cable although the same length. This caused more resistance in the smaller cable which may (or may not) have been the entire reason for the difference in sound. They have been accused, because of this, of misleading the customer. The idea behind the accusations is this: the customer could use less expensive cable (than that of the major manufacturer) of the same gauge and it would sound the same, thus the customer is mislead. Let us examine this idea from another point of view: The major manufacturer determined that the majority of their target audience used the smaller size cable, and thus their cable would make a difference in most cases. Most customers do not want long electronics explanations and told to go to a hardware store and pick up this awg of cable, etc (I speak from experience here). They don't know what an AWG is, what resistance is, what kind of insulation will not eat the copper conductors over time, how to know if they are getting copper conductors, etc. They want a recommendation, I:E: This cable will probably make your system sound better. Most need to deal with persons and brands they can trust, without long involved explanations and being told to go do it themselves. The bottom line on this particular issue is: the brand name cable did what it claimed, no more and no less. It sounded better than the other cable. I mention this because I found flames on the internet about this particular demonstration. My advice is use common sense and the distance chart above.

Other issues of cable quality to consider center around build quality. Is it flexible enough? Is it so thin it will break over time? Does it have strain reliefs on the connectors? Do I need it in white to match the wall color? etc.

Multiple Speakers on a single amplifier

This subject requires it's own treatment, found here . Don't connect multiple sets of speakers without some form of impedance compensation because you will most likely end up with some form of amplifier damage.

In Wall Wiring

If your speakers are to be installed in-wall, you will need speaker cable rated cl3 or equivalent. It is illegal to install cable not rated for in wall installation because of fire rating codes, not to mention your own safety. In addition, good in wall cable will be hardier than standard stuff, allowing for better pulling without damaging the cable. Another factor is the fact that decent in wall cable has a specific number of twists per inch of cable, providing some self shielding capability from interference from other wiring installed in wall. If you need better shielding, shielded in wall cable is available which provides additional foil shielding, with a drain lead, in addition to the twists. Our usual method of connecting the speakers is to go from a good wall plate with binding posts with 4 conductor 16 gauge cable to either the first speaker, or an in wall volume control if used, then to the first speaker of a stereo pair. We then route from there with two conductor cable to the second speaker. Shielded cable is seldom needed, but may be if you must run cable parallel and closer than 1 foot to other installed wiring. You should keep all audio cables away from other cables, and if they must cross you should try to ensure they cross at right angles. If you end up with hum or noise in your system, you will not be able to remove it without re-routing your cable or replacing it with shielded cable. This could be a real nuisance, so if you do it, do it right the first time. (Click here to see our in wall cable)

**Damping Factor:

This is a measurement of how much a particular amplifier damps excess movement of a speaker cone. The excess movement, mostly due to inertia, generates a voltage counter to the amplifier voltage. This is termed BACK-EMF. The emf means electromotive force, a fancy word for a voltage and current. An amplifiers effectiveness at damping this undesired movement depend on the internal resistance and output impedance of the amplifier plus the resistance of the speaker cables. Larger speaker cables provide lower resistance, making the amplifier more effective at damping this excess movement.

For more about the speaker driver construction that causes back emf, see our article on speaker cabinet design .

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