Red positive or negative?

Roger Crawford · From: Griffin, GA USA

In my line of work, black is hot, white is neutral and green is ground. In electronics, which is which? Also, I've been told the basket on Peavet BW speakers move forward when "energized" while other makes move rearward. Any truth to that and how can you check to be sure the speaker is wired in proper phase?

Ken Fox · From: Nashville GA USA

Peavey is phased normal, a positive pressure (voltage) on the red terminal of the speaker will cause a positive (forward) movement of the cone. JBL speakers were backwards to the industry standard for years. I have read they are now changing to be in step with the rest of the world.

I use a 9 volt battery to test phase, just a quick tap to the terminals will move the cone. Do not apply DC voltage to long to it as it will heat ans could cause voice coil damage.

Peavey uses blue (negative) and yellow (positive ) wires for speaker hookup. Usually black is common (negative) and red or white are the positive.

Craig A Davidson · From: Wisconsin Rapids, Wisconsin USA

so on a JBL if it wired right it will still jump forward with a nine volt touching pos. to pos. ?

Jack Stoner · From: Kansas City, MO

I came up with an out of phase condition hooking up my Nashville 1000 and Nashville 112. Both were wired "correctly" as far as the wire colors from the amp and connected correctly on the speakers. I didn't check to see whether a speaker was wired "wrong" or if the wires on the circuit boards were reversed. Just reversed the wires at one speaker and they were fine.

This is not usually a problem since each amp only has one speaker and usually they are used by themselves. But these particular pair together were out of phase, wired as they came from the factory.

John Daugherty · From: Rolla, Missouri, USA

I have learned through the years, not to rely on the color of wires. I think many manufacturers buy wire the cheapest way they can at the time. Price is first, color is second.

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www.phelpscountychoppers.com/steelguitar

Jim Sliff · From: Lawndale California, USA

John's right - color was and is often secondary. Many, many amps, especially boutique guitar amps, use rip cord (standard lamp or extension cord) for speaker wire, which has NO color designation (and is also the best speaker wire you can use - stay away from all the over-hyped "name-brand" speaker wires unless you're a boutique audiophile fan).

Phasing, though, is completely unimportant unless you run more than one speaker or amp with your guitar. Then you have to make sure the phasing is the same (using the battery test) or else you will suffer from "phase cancellation" and lose a bunch of frequencies. It often sounds like the guitar just "goes away".

On a one-speaker setup it makes no difference.

David Spangler · From: Kerrville, TX USA

What Jim said.

Zip cord does have grooves in one side of the insulation, although I need bifocals and good light to see it. The 16 gauge works great for moderate lengths.

Those cheap Wal-Mart 16 gauge extension cords make good speaker wire.

The Monster and other "boutique" cables' benefits can be detected by dogs in blind A/B tests.

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David Spangler

Jon Light · From: Saugerties, NY

Ray Minich · From: Bradford, Pa. Frozen Tundra

Harold Dye · From: Cullman, Alabama, USA

Guys I am electroniclly challenged so this may be a stupid question. When you are talking speaker wire I assume you are talking about the wire going from the speaker jack to the speaker. Lamp or extension cord was mentioned for this purpose. Someone else mentioned wire by Monster and the like, and when I think of this I think of guitar cable etc. Will the lamp or extension cord work if used to go from the Amp( as in a rack situation) to the speakers?

Jon Light · From: Saugerties, NY

Yes--from the amp to the speaker. DO NOT USE guitar cable. It is absolutely wrong. You want wire with the two strands side-by-side, each of equal thickness. Guitar cable has one wire wrapped around another (very thin) strand and this is not enough beef to conduct the amount of signal being handled. It will rob tone and, more important, it will get hot and it will create problems for the amp (or burn it up trying).

----Monster and other high end companies make speaker wire and all sorts of other specialty stuff besides guitar cables.

[This message was edited by Jon Light on 26 November 2005 at 09:08 AM.]

Jim Sliff · From: Lawndale California, USA

Jon - what he's saying is that boutique and hyped-up cables are not worth the money. You're paying for marketing and BS.

Smiley Roberts · From: Hendersonville,Tn. 37075

T. C. Furlong · From: Lake County, Illinois, USA

Harold, Speaker wire is the wire that connects between the output of the amplifier and the terminals of the speaker It can be inside or outside of a cabinet. It is called unshielded cable. Monster makes all kinds of cables. If I am not mistaken, they started with heavy guage speaker cable. For most applications, lamp cord will work fine for short runs of speaker cable. The general rule for speakers is, get the heaviest stranded wire you can afford and you shouldn't experience any loss in the cable.

Ray, positive polarity in a loudspeaker cone is when the cone moves toward the listener and away from the magnet when the positive terminal of a DC source such as a 9V battery, is connected to the positive terminal of the loudspeaker. The only time polarity matters is when there are two loudspeakers being used at the same time with a common signal. If two speakers are connected out of polarity, depending on the distance between them, they will be out of phase at certain frequencies and in phase at others. If they are close together, all of the lower frequencies will be out of phase and will be reduced in level by cancellation. If they are connected in polarity, all of the lower frequencies will be in phase and will increase in level because they add. At higher frequencies, regardless of the polarity, they will add at some frequencies and cancel at others.

So an easy way to tell if your speakers are in polarity is to listen to your rig with just one speaker, play a low note, connect the second speaker, play a low note again. If you hear more lows, the two speakers are in polarity. If you hear a reduced amount of lows, the two speakers are out of polarity.

For the technically oriented, phase is frequency dependent and is measured in degrees. Polarity is either positive or negative and negative is always 180 degrees out of phase with positive.

JBL adopted the convention of the + at the red terminal moving the cone rearward because woofers were normally used in passive two way cabinets that had a basic crossover network that had a second order filter for the high frequency driver. These filters ended up flipping the phase of the high frequencies by 180 degrees. So they just magnetized the woofer so that it would add in the area that the woofer and tweeter would overlap.
TC

David Spangler · From: Kerrville, TX USA

Jon, I was trying to be funny about the [Monster] boutique cables before having my first cup of coffee.

What I read about them in an article several years ago, is that the high frequency response of Monster speaker cables is extended to nearly 400,000 Hz, which might be important to dogs (since dogs can hear higher frequencies than people).

The article went on to say that people could not hear the difference in blind A/B tests.

Since I have never bought boutique cables and my hearing is damaged from years of gigging, the information I offer here is "hearsay".

[This message was edited by David Spangler on 26 November 2005 at 03:21 PM.]

Jack Stoner · From: Kansas City, MO

The "look" of a cable is unimportant. The electrical characteristics is the issue.

Generally, price is an indicator of quality but with the "boutique" cables it's not always the case.

I was looking at the Monster web site about a year ago at their "guitar" cables and there was a lot of "salesman" hype but nowhere did they list the electrical characteristics of their cables, e.g. capacitance per foot.

John Daugherty · From: Rolla, Missouri, USA

I seem to recall a "Consumer Reports" article stating that the so called oxygen free and other sales hyped wire is a waste of money. I already knew this.
The main thing to look for in good audio cables is a lot of shielding (tightly woven outside shield). For short lengths (10') most audio cables do not noticeably affect the frequency response. However, I have run onto a few bargain cables that did have a noticeable effect.
Since speaker wires are not shielded, you only worry about signal loss. This is minimized by using a heavy gauge wire with a good separation between the two wires (don't use a twisted pair). The longer the cable is, the heavier the gauge needs to be. As has been mentioned, 18 or 16 gauge works well in most cases.

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www.phelpscountychoppers.com/steelguitar

Jon Light · From: Saugerties, NY

Here is a little utility for calculating wire gauge per wattage per length.
http://www.webervst.com/gauge.htm

Dave Grafe · From: Hudson River Valley NY

T. C. Furlong · From: Lake County, Illinois, USA

Jack Stoner · From: Kansas City, MO

On a short run, such as inside a Peavey amp, #16 (stranded) wire will more than suffice as long as it's "good" grade wire (electrical characteristics - not the hype of some brands).

Jerry Roller · From: Van Buren, Arkansas USA

OK, it has been a while since I asked a stupid question, so here goes. If my amp is sitting next to a 6 string players amp and his speaker is out of phase with mine and we both are playing the same notes, can we be cancelling out the others frequencies?
Jerry

Ray Minich · From: Bradford, Pa. Frozen Tundra

Yes, Theoretically, but maybe not 100% due to waveshape factors. That's the idea behind noise cancelling headphones and such.

[This message was edited by Ray Minich on 28 November 2005 at 11:40 AM.]

Dave Grafe · From: Hudson River Valley NY

Jerry, even if you both had the same pickups, strings, etc. and picking style so that the waveforms were magically identical, you would still only have that problem if you were both plucking the strings at EXACTLY the same moment, not a fraction of millisecond before or after each other. Even if the notes are picked at the same time, it will only be apparent to a listener who is EXACTLY the same distance from both speaker cones. Even then, it won't necessarily be a bad sound, remember that chorusing, flanging, etc. are all effects created by delaying a signal and re-introducing it so that it is deliberately out-of-phase with the original, dry signal.

Jack, it is quite true that the smaller wire over that short run "will suffice" and won't change the actual electrical power transmitted much at all, but the damping factor (and the resulting clarity at high power) WILL be affected by a significant amount. At 200 watts or more this is going to be audible to much more than just canine ears. With a reduction in damping factor you don't lose volume (sometimes it even seems louder in fact, due to speaker cone resonance and reactance), you lose fidelity - for some this is an issue, for some it is not.

[This message was edited by Dave Grafe on 28 November 2005 at 03:12 PM.]

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