Article View: rec.audio
Article #5398Re: Speaker wires
From: Andrew Hume
Date: Sat, 02 Jan 1993 23:48
Date: Sat, 02 Jan 1993 23:48
121 lines
7251 bytes
7251 bytes
In article <1i4pl0INNbmu@iskut.ucs.ubc.ca>, twong@civil.ubc.ca (Thomas Wong) writes: > > Can anyone describe the differences between speaker wires? What > characteristic should we pay most attention to? What is a good gauge to > use....etc? Thanks. > > Thomas. for your edification i replay the relevant part of teh FAQ. 16.0 Wire More than any other topic, speaker cables and equipment interconnects seem to use up rec.audio bandwidth echoing the same theoretical arguments, testimonials, and opinions. Controversy can be stimulating, educational, and also amusing. Please try to keep postings aimed at one of those three goals, and avoid the insults and emotion. Also, try to avoid echoing a common position or principal, as described below. 16.1 Do speaker cables matter? Cables are connectors attached to wires. Wires generally have multiple conductors optionally surrounded by a shield and outer insulative covering. Cables can introduce noise into the signal, act as a filter (and thus change the frequency response of the system), and provide non-linearities from improper (intermittent/loose) connections to or between the connectors. It is quite scientifically conceivable that some cables do cause a difference in sound, because of the differences in DC resistance, interconductor capacitance, and connector attachment alone. The effects of exotic conductor weaving and materials are not so well established. In general, these effects (once we eliminate DC resistance), seem to be small. However, if your system is at least fairly good, then some folks have observed (although not in an experimental, double-blind sense) significant differences in system performance with different cables. The effects are said to be quite system specific; the only real guideline is to try them and see which ones seem to sound better in your system. Roughly speaking, the price ranges for speaker cables is low (under $1/ft), medium (under $6-8/ft), and high (up to $100/ft and more). Try to arrange it so you can trial such cables; at several hundred dollars per set, experiments can be expensive. In any system or experiment, it is essential that the differences between cables be separated from the differences between connectors. You should have an EXTREMELY solid connection between cable and speaker. Speakers operate at very low impedances, so that bad connections will create significant artifacts or signal losses at any power level. For example, if the connection has a linear resistance of just 1 ohm, the speaker damping factor will be dramatically reduced, making bass muddy. If the connection contains imperfect metal oxides, then a slightly rectifying junction will block the signal, producing compression, distortion, and other non-linear effects. 16.2 What speaker cables are commercially available and how good are they? There is a wide range of speaker wire available, ranging from 30ga zip cord (~$.10/ft) to exotic wires costing over $300/ft. The material used ranges from copper to oxygen-free copper (OFC) to silver. (There are a bunch of others as well.) 16.3 What can I use for budget speaker cables? First, a few words on terminology. Wire is sized by AWG or BS gage number. Larger numbers represent smaller wire. AWG 40 (also called 40 gage) is as fine as human hair. AWG 12 is 2mm or .081" diameter. Some wire is classified as solid, because it contains one strand per conductor. Other wire is called stranded, because it consists of many strands per conductor. Stranded wire is far more flexible than solid wire. Most wire is made from drawn copper. Some wire is sold that is claimed to be made with a process that produces oxygen-free copper. Oxygen-free copper has a different metallurgical structure than common copper and may or may not conduct current better. Some critical listeners have reported excellent sound from large diameter solid copper wire, such as home wiring "Romex 12-2". At least one expert has said that common 18-gage solid copper hook-up wire sold by Radio Shack also works very well. Also recommended on a budget is Sound King wire, a 12 gage oxygen free copper stranded cable. This is available from MCM Electronics for $.39/ft. The scientific literature indicates that small gauge wire generally sounds worse than large gauge and that resistance-related effects of the cable can be eliminated by using at least 12 gage wire, particularly for long runs. Of course, shorter runs are always preferred, because they come much closer to the ideal zero-length wire, with no resistance, no capacitance, no inductance, and no change in signal. 16.4 What can I use for budget speaker connectors? The worst connectors are push-down, or spring terminals. Screw terminals with solid copper wire are much better. Gold-plated binding posts and gold spade lugs are inexpensive by audiophile standards and are extremely stable. Binding posts with spade lugs can be tightened to get a very good mechanical joint, and may offer the lowest electrical resistance of any connector. Gold plated banana plugs and jacks are also very good speaker terminals. Good ones are more expensive than gold spade lugs, however, they also provide a bigger area of contact, and are more convenient when you must frequently reconfigure the system. Banana plugs should be periodically monitored for corrosion and loss of spring tension. Monster offers a banana-plug connector with an expanding center pin that forms an even better connection than common gold banana plugs. At approximately $25 per pair, the Monster banana plugs aren't a budget connector. All else equal, connectors with gold surfaces are better than connectors with any other surface. This is for two reasons. First, gold is extremely inert, meaning that unless gold is exposed to very harsh chemicals or harsh vapors, it will not corrode or oxidize. It will remain a pure, low-resistance conductor. Second, gold is quite soft, so that if a gold-plated connector is squeezed between two metal surfaces, it will deform slightly to fill scratches and voids, giving a very broad, low-resistance contact area. Corrosion of connectors is often a problem. Gold-plated terminals and connectors somewhat avoid this problem; problems with other connectors can be mitigated by unplugging and replugging the connector on a regular basis, cleaning the contact areas with a pencil eraser, or by using a contact enhancer such as Cramolin or Tweek. When you use a contact enhancer, be very sure to follow the directions, and avoid spreading enhancer about your equipment.
Technical Details
Message-ID:
<24536@alice.att.com>Path:
arc1-ca.pugleaf.net!sparky!uunet!zaphod.mps.ohio-state.edu!uwm.edu!linac!att!att!allegra!alice!andrewReferences:
<1i4pl0INNbmu@iskut.ucs.ubc.ca>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!sparky!uunet!zaphod.mps.ohio-state.edu!uwm.edu!linac!att!att!allegra!alice!andrew From: andrew@alice.att.com (Andrew Hume) Newsgroups: rec.audio Subject: Re: Speaker wires Summary: read the FAQ Message-ID: <24536@alice.att.com> Date: 2 Jan 93 23:48:44 GMT Article-I.D.: alice.24536 References: <1i4pl0INNbmu@iskut.ucs.ubc.ca> Organization: AT&T Bell Laboratories, Murray Hill NJ Lines: 121