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bamaspiveys
05-29-2008, 07:40 AM
So I have four 4ohm speakers, I want to put two of them in parallel to achieve a 2ohm load on one channel of my amp and the other two in parallel to achieve a 2ohm load on the other channel.

So here is the question:

Can I connect the + terminal of speaker #1 to the +terminal on speaker #2, then connect the + terminal of speaker #1 to the amp?

Or do I have to run dedicated wire from each speaker all the way to the amp?

Or can I spice the speaker wire at some point beteen the speakers and the amp?

Obviously I would do the same thing on the negative side as the positive....


Not an expert on resistance, but it seems like in my first example the speaker directly connected to the amp would not have the 2ohm load, only the second speaker in the chain.

ian ashton
05-29-2008, 10:00 AM
Can I connect the + terminal of speaker #1 to the +terminal on speaker #2, then connect the + terminal of speaker #1 to the amp?


You can do it this way, no problem. In fact, when I used to compete in car audio this is how I wired the voice-coils of my subs at certain events, never had an issue. Just make sure the wire you are running to the speaker (s) is heavy enough gauge (I'd say 14awg at the very least, 12 would be best.)

pickle311
05-29-2008, 09:48 PM
It will sound better if you wire them up series parallel.
Take speakers 1 and 2, run a wire from the + on speaker 1 to the - on speaker 2.
Now connect the + on speaker 2 to the + on the amp, and the - on speaker 1 to the - on the amp.

Now do the smame exact thing with speakers 3 and 4. This will put each pair of speakers in an 8 ohm series configuration. Then you can parallel the 2 pairs together for a 4 ohm mono configuration and bridge your amp safely.

This will allow the subs to play mono and get the full sound out of them. Running subs stereo just doesn't work that well, and you will get the maximum power out of your amp to them.

Good luck.

ian ashton
05-29-2008, 10:32 PM
I think that would only make sense if they are subs that he is wiring up though; to me it sounds like he has 2 pairs of full range speakers, where mono would sound odd with certain songs.

bamaspiveys
05-30-2008, 12:28 PM
These are not Subs, they are tower speakers

zabooda
05-30-2008, 02:04 PM
Hook + to + on everything otherwise the speakers will be 180 degrees out of sync. One speaker cone is going out while the other is going in due to current flow through the speaker coils are in opposite directions.

JesseC
05-30-2008, 02:57 PM
So I have four 4ohm speakers, I want to put two of them in parallel to achieve a 2ohm load on one channel of my amp and the other two in parallel to achieve a 2ohm load on the other channel.

So here is the question:

Can I connect the + terminal of speaker #1 to the +terminal on speaker #2, then connect the + terminal of speaker #1 to the amp?



The short answer is yes , they can be wired as you stated.This will also cut down on the number of wires you will have to route through the tower. Just wire one to the other and run a single pair down through the tower. I would use at least a 14 gauge wire.

ian ashton
05-30-2008, 03:28 PM
Hook + to + on everything otherwise the speakers will be 180 degrees out of sync. One speaker cone is going out while the other is going in due to current flow through the speaker coils are in opposite directions.

Not at all right. If you wire 2 subwoofers that are both facing the same direction exactly opposite they will cancel each other out, full range speakers don't typically experiance the same phenomenon, as the acoustics of the setting (car, boat, house) will break it up.

Wire them how you originally thought, it will be exactly what you want, as Jessie said.

zabooda
05-30-2008, 07:16 PM
Well Ian your right again. I wouldn't have thought one would wire subs opposite polarity with each other so they can enjoy the effect of creating destructive wave interference and the same would apply to any speaker wired that way.

FROM:
http://www.dccwiki.com/Speaker

Phasing or Polarity
Phasing means that in an installation with multiple speakers, all speakers move in the same direction. This is accomplished by wiring all connections in the same manner. Speakers usually have an indicator for polarity at their terminals, so if one speaker is connected from it's plus terminal to the plus terminal on the amplier, the other must be connected in the same manner to it's amplifier.

Two terms describe speaker operation: Compression and Rarifaction. Compression: the speaker movement compresses the air in front of the cone. Rarifaction: The speaker cone moves in the opposite direction, reducing the air pressure in front of the cone.

Incorrect phasing will result in poor sound quality, as one speaker is cancelling out the other (Compression versus rarifaction.) If wiring two speakers in series, the minus terminal on the first speaker connects to the plus terminal on the second one. In parallel, plus to plus. The movement of the speaker cones is in phase, enhancing the sound.

Incorrect phasing tends to attenuate the lower frequencies.

As a EE sometimes I miss a few things but I'm always afraid of going to jail when I violate the right hand rule and Faraday's Law.

ian ashton
05-31-2008, 06:34 PM
All I'm saying is that if you go wire one full range speaker in your boat backwards I promise you that it will sound the exact same. :LOL: