Car/Boat audio instalation question

castaway

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Just installing an Aiwa Car CD/radio into 'Fairweather', nice liitle buy from Ebay. Also 4x waterproof speakers from the same source, very good value as well.

Question is : As there is no loom to connect to, I am cutting off the 8 wire speaker plug from the 8 speaker cables coming from the back of the radio unit...these are all colour coded and the manual specifies which cable colour goes to which speaker (ie. front RH or back LH etc.) and which is neg or pos.

What I don't know is which connecter tag on the back of the speakers takes the neg wire or pos wire.....One tag is bigger than the other.

Any help is welcome!

Thanks Nick

www.yachtsite.co.uk/fairweather
 

jerryat

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Yep, agree with knotgood. Just fitted a Pioneer CD/tuner in my boat and the positive connection to the matching Pioneer W/P speakers was to the large connector. As mentioned, do ensure that this is adhered to for all the speakers or there is apparently a risk of damaging the unit (in my case anyway)!!

Cheers Jerry
 

dedwards

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I didn't think it would cause damage if you had one connected the wrong way round. It should just cause that speaker to operate out of phase with the others and reduce sound quality (though i've never noticed it) i.e. when the other speakers' cones are fully forwards, that speaker's cone would be fully backwards.

The only way I can think of damaging the unit with the speaker wiring is to confuse the negative with earth and join them either together or to an earthing point.
 

dmayes

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The difference it will make is if one of the connectors is earthed through the metal of the speaker. If you then missmatch the earth connections through a car bodywork it will fuse out as one of the wires will go straight through the frame of the car. When you install the speakers on a boat they will probably not have an earth connection between the speakers and the radio, unless you have a metal boat. So assuming you have no earth connection, then either way round will work, but do keep them all the same or you will have one speakers paper cone going into the speaker and the other on the next speaker going out of that speaker on the same part of the sound wave. Does that make sense?
 

BobOwen

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In my experience having two speakers that are in opposite phase makes a big difference. Thats how noise cancelling systems work. Ensure that each speaker has the same configuration as the others and you should be OK.

Many speakers have two different size lugs - the smaller usually being the negative.

It will work with any configuration - but should sound better if they are all in phase.
 

tsmyth

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I seem to recall that, in theory, the postive and negative leads must be connected as designed to get "proper" sound reproduction, but I cannot recall the rasoning involed. Intuitively, however, it does seem to make sense. Perhaps someone could explain.

Ray
 

William_H

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Many modern bcar radios use a bridge amplifier for more power from 12 volts. This means that both the + and -ve speaker wires must not be connected to the chasis or negative power line. The positive and negative names for the speaker wires relates to phasing as already explained. Phasing doesn't matter if the speakers are widely spaced however if they are near to one another then the push of one speaker can cancell the pull of the other especially at low frequencies if they are out of phase.
good luck olewill
 

fireball

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Out of Phase speaker spacing

How widely spaced do you think the speakers would need to be before you don't notice the out of phase? I notice in all my domestic setups - speakers 10' apart and noticed in the student union with the speakers 50' apart (slightly different volume level there though! /forums/images/graemlins/tongue.gif)
Generally, out of phase speakers will manifest in lack in the lower end of the spectrum, when you situate yourself midway between the source this effect will be greatest and sounds very strange ... !! still - simple enough to swap around...
 

dmayes

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Re: Out of Phase speaker spacing

The distance of the speakers, in theory, should be the same distance as the microphones were when it is recorded. Somewhere around 10 feet apart and 3 to four feet high for stereo effect, I think. This should then reproduce what the microphones "heard". I am not sure about the front to back settings.
 

fireball

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Re: Out of Phase speaker spacing

hmm .. better get back to the recording studio and stop them close miking all that kit then!! No .. only joking - different recording techniques for different sources - all dependant on the effect your after.
I believe the spacing for speakers though, should be a ratio to include where the listener is... on a boat this is usually impracticle and I've just mounted ours low down in the saloon seats (about 8 inches off the sole) to give an even level of sound throughout - rather than mounting at (sitting) head level where one person gets full blast and the others can't hear it!
 
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