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curt
06-25-2007, 01:50 PM
How does one determine the + & - connections on a radio speaker. Is the - ground and the + non ground? My tags came off the wires as to what is + & what is - .

JDP
06-25-2007, 02:52 PM
Really makes no difference unless you have two, then you need them wired the same, but ground the negative for a one wire setup.

JDP/Maryland
66 Sports sedan
64 Daytona HT/R2 clone
64 Daytona R2
63 GT R2
63 Lark 2 door
62 Gt Hawk
62 Lark 2 door
60 Lark HT-60Hawk
59 3E truck
58 Starlight
52 & 53 Starliner
51 Commander

starlightchamp
06-25-2007, 03:33 PM
Speaker polarity is important so that the air waves moved by the speaker cone, to create sound, do not add together and cause some cancelling. It is most prevalent at low frequencies (bass) where the waves spread more than the directional "tweeter" frequencies. One way to check that both speaker cones/diaphrams are not cancelling , is to apply a low voltage battery, 1 to 1.5 volts to the terminals and notice if the cone moves forward or backwards. mark the terminal + for forward motion on both speakers and attach the "hot" speaker wire, the one not grounded , from your driver amplifier, to the+ terminal. This is called "phasing" in audio circles. Even if your speakers are marked, it's a good idea to check them.
...Dick

terrymb
06-26-2007, 10:50 PM
An easy way to check for proper phasing is to play something with some bass, and stick your head right in the middle of the 2 speakers. If the bass drops out, change the wiring on one of the speakers.

1952 Commander Starlight

JDP
06-26-2007, 11:12 PM
Again, phasing is only a issue with 2 or more speakers, be they left and right stereo or front to rear mono. Move the balance or fader to the middle and if the bass drops, swap the wires on one speaker.

JDP/Maryland
66 Sports sedan
64 Daytona HT/R2 clone
64 Daytona R2
63 GT R2
63 Lark 2 door
62 Gt Hawk
62 Lark 2 door
60 Lark HT-60Hawk
59 3E truck
58 Starlight
52 & 53 Starliner
51 Commander

jimmijim8
06-27-2007, 10:50 AM
A speaker or speakers will not perform properly if they are not properly wired. Minus to - and plus to + from the output of your amplifier or radio. If your speaker is not marked for polarity, use the 1.5 volt battery method for determining polarity. For connecting speakers in series for example (two 8 ohm in series, (+side of output from a radio or amp to + on the speaker then run a jumper from the other side of this very same speaker to the + side of speaker number two. Run the other side of this second speaker to gnd. Two 8 0hm spkrs. in series are equal to 16 ohms. Parallel wiring of speakers is what decreases the total impedance. (for instance, if your output on your music is designed to be matched to an 8 ohm load and you wish to have two speakers, two 16 ohm speakers in parallel will do. All speaker combinations whether series, parallel, or series parallel are subject to
ohms law theory for D.C. circuitry as far as total impedance or ohms For example 2---8 ohms in series =16 ohms. 2-----8 ohms in parallel =4 ohms. Power handling capabilities will add up for whatever speakers rating. are in each circuit. If you have 250 watts of power handling capability in your system being driven by a 7 watt Studebaker radio, I would say that is a bit of overkill.
Speakers do not make power but rather transform power into an audible frequency. They should be phased to work as good as the were designed to do. It's easier to push a car by hand than pull one. jimmijim

John Kirchhoff
06-27-2007, 12:51 PM
jimmijim made a very good point about the power output of the radio. Normally, the higher the maximum power rating of a speaker, the higher the radio or amplifier power output needed to make it sound good. For example, a speaker rated 90 watts max may need a radio or amp producing a minimum of 30 watts while a 45 watt speaker may need a minimum of 15 watts. Stick a high wattage speaker on a wimpy radio and it'll have a tinny, bass deficient sound. I just replaced the radio on my bike with one rated at 50 watts per channel going into 4" 90 watt speakers. The sound was wimpy, wimpy, wimpy. Last night I got the 250 watt/channel amp hooked up and the sound improvment is remarkable. Lots more bass with less distortion at a higher volume. I sometimes doubt the power ratings advertised for the Chinese made stuff because theoretically my radio+amp should blow the cones clear out of the speakers but instead it seems just right. So the moral of the story is, if you have a wimpy radio, a low wattage speaker of bigger dimensions may improve the bass response but trying to power a large, high power speaker is likely to be disappointing.

bekglm1
06-29-2007, 03:11 PM
It does make considerable difference. The speaker is essentially a bi-directional electromagnetic motor. The surround is designed to support cone movement in a linear phased directional path. If a speaker is wirred backwards, than the initial pulse goes in, instead of out, and you do not get the sound wave propegation you would were it to be correctley polarized. 2 speakers out of phase cause low frequency cancelation by eminating non-inphased standing waves, which cancel each other's amplitude, or basically sound emenation. More importantley, out of phase speakers can cause serious headaches, and disorrientation, something you do not want while driving down the road at 60 mph. Out of phase sound emination is used as a counter measure on battle fields to dissorient the opposing troops.

Ben

bekglm1@aol.com
SIAR/ Special Interest Autos and Restorations
59 Canadian Lark 2 door 63 full flow 6 cyl 3 OD
59 Silver Hawk 289 4 bbl 3 OD
62 Lark Wagon 335 hp 4 bolt small block GM/built THM 350/Versilles RE w/discs
62 Lark Cruiser 259 auto, TT
62 Daytona 289 4 bbl PS Auto, TT

JDP
06-29-2007, 03:50 PM
For the third time, speaker polarity is only a issue with more then one speaker. Way back in the day when speakers used electro magnets it may have made a difference, but not with a permanent magnet. Yes, the cone will move in on the positive part of the sine wave and not out, but that makes zero difference unless it's paired with another.
Also, the comments about power rating is also inaccurate. How much power a speaker needs is determined by it's efficiency not it's power dissipation. i.e. a speaker could be rated for 50 Watts and have a 83db/watt efficiency and another could be rated at 93db/watt with a 100 watt rating. In that case, the 100 watt speaker would sound twice a loud at a given input as the 50 watt. It also should be remembered that a factory Studebaker radio's output is at best, perhaps 2 watts RMS. Impedance matching is important with many factory radio's since they use complementary symmetry output transistors that are greatly effected but the load impedance.
I knew the 100K your taxes paid for my two years of electronic training in the Navy would be paid back at some point.:)

JDP/Maryland
66 Sports sedan
64 Daytona HT/R2 clone
64 Daytona R2
63 GT R2
63 Lark 2 door
62 Gt Hawk
62 Lark 2 door
60 Lark HT-60Hawk
59 3E truck
58 Starlight
52 & 53 Starliner
51 Commander

JDP
06-29-2007, 03:51 PM
For the third time, speaker polarity is only a issue with more then one speaker. way back in the day when speakers used electro magnets it may have made a difference, but not with a permanent magnet. Yes, the cone will move in on the positive part of the sine wave and not out, but that makes zero difference unless it's paired with another.
Also, the comments about power rating is also inaccurate. How much power a speaker needs is determined by it's efficiency not it's power dissipation. i.e. a speaker could be rated for 50 Watts and have a 83db/watt efficiency and another could be rated at 93db/watt with a 100 watt rating. In that case, the 100 watt speaker would sound twice a loud at a given input as the 50 watt. It also should be remembered that a factory Studebaker radio's output is at best, perhaps 2 watts RMS. Impedance matching is important with many factory radio's since they use complementary symmetry output transistors that are greatly effected by the load impedance.
I knew the 100K your taxes paid for my two years of electronic training in the Navy would be paid back at some point.:)


JDP/Maryland
66 Sports sedan
64 Daytona HT/R2 clone
64 Daytona R2
63 GT R2
63 Lark 2 door
62 Gt Hawk
62 Lark 2 door
60 Lark HT-60Hawk
59 3E truck
58 Starlight
52 & 53 Starliner
51 Commander

bekglm1
06-29-2007, 10:44 PM
JDP:

third, fourth, fifth, it just doesn't matter, your wrong. I will put my 30 years of doing acoustical physics up against your 2 years in Navy electronics any day of the week. Cones are engineered to produce the principle, and primary 180 degrees of a sine wave in a positive excrusion. Period. It will always work better and be more efficient at producing lower frequencies. One of the responders was also correct in that if you apply dc voltage to the cone the first polarity that causes positive or outward motion of teh cone is the correct polarity.

Ben

bekglm1@aol.com
SIAR/ Special Interest Autos and Restorations
59 Canadian Lark 2 door 63 full flow 6 cyl 3 OD
59 Silver Hawk 289 4 bbl 3 OD
62 Lark Wagon 335 hp 4 bolt small block GM/built THM 350/Versilles RE w/discs
62 Lark Cruiser 259 auto, TT
62 Daytona 289 4 bbl PS Auto, TT
55 President 289 4B PS PB
54 Commander
56 Flight Hawk
53 Champion
53 Champ R6 Bonneville Race Car "MAYA" Raymond's Revenge Racing Team (3RT Racing)

JDP
06-29-2007, 11:30 PM
I'll defer to your expertise, but it goes against anything I've learned or read about a alternating sine wave. Here's all I found on the subject and it was how I was taught. Kinda silly to argue about it since it's easy to check if you are concerned and we're just wasting bandwidth. If you think this argument is silly, try to convince a audiophile that a he does not need $1000/meter patch cords for his tube amp.

"Re: How can I tell which connection on a speaker is 'positive'?
Date: Mon Oct 4 16:05:30 1999
Posted By: Steve Czarnecki, senior technical staff member, Lockheed Martin
Area of science: Engineering
ID: 935895114.Eg Message:


Speakers, being made to work with alternating current waveforms, don't have
a "positive" or "negative" polarity per se. A single speaker will work
just fine connected to an amplifier without regard to polarity.

Multiple speakers, on the other hand, must be phased correctly to work in
unison properly. This is true for multiple speakers within a single
enclosure, or a set of speaker connected to multiple amplifier channels.

By "correct phasing", what's required is that all the speaker cones
move in the same direction when the source amplifier(s) apply a voltage of
a given polarity. This synchronization ensures that when the amplifier produces
a positive voltage, all the speakers compress the air in front of them. If
care is not taken in this regard, some speaker cones are compressing the
air while others are expanding the air -- effectively, the speakers are
working against each other."


http://www.madsci.org/posts/archives/oct99/939144118.Eg.r.html:)

JDP/Maryland
66 Sports sedan
64 Daytona HT/R2 clone
64 Daytona R2
63 GT R2
63 Lark 2 door
62 Gt Hawk
62 Lark 2 door
60 Lark HT-60Hawk
59 3E truck
58 Starlight
52 & 53 Starliner
51 Commander

John Kirchhoff
06-30-2007, 12:10 PM
JDP, I'd be very interested in you explaining in more depth how watts and db/watt affects speaker output. If you think it would be too boring or off subject, write me personally. I'd appreciate it because I know there's plenty of people out there much smarter than me and the only chance I have is ask questions and listen to whay they have to say. Thanks.