Question about connecting woofers to an amp

[scooby84 10+ year member]

I'm thinking about buying a mono block amp from a friend. This amp, however, only has 2 speaker wire terminals, one positive and one negative. I have two subs in a box, therefore i have 4 wires, 2 positives and 2 negatives. My last mono block actually had 4 terminals, 2 positive and 2 negative. How do I connect my subs to this new amp? Or is it even possible?

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[ahole-ic]

I'm thinking about buying a mono block amp from a friend. This amp, however, only has 2 speaker wire terminals, one positive and one negative. I have two subs in a box, therefore i have 4 wires, 2 positives and 2 negatives. My last mono block actually had 4 terminals, 2 positive and 2 negative. How do I connect my subs to this new amp? Or is it even possible?

If you want to do it cleanly, you can buy 2 distribution blocks. The other way is to just insert both positive wires into the + terminal and both negatives into the - terminal. This wires you in parallel. If you were to wire in series, it would solve the wiring problem but raise your impedence thus lowering the output of your amplifier.

 

[FenixAudio 10+ year member]

If you want to do it cleanly, you can buy 2 distribution blocks. The other way is to just insert both positive wires into the + terminal and both negatives into the - terminal. This wires you in parallel. If you were to wire in series, it would solve the wiring problem but raise your impedence thus lowering the output of your amplifier.

this is correct. ecrack, i owe you an apology. the t1500 is not regulated. my bad. it does max out at 15.5 volts before damage though

 

[ahole-ic]

this is correct. ecrack, i owe you an apology. the t1500 is not regulated. my bad. it does max out at 15.5 volts before damage though

No need to apologize. There was only ever 1 perfect person.

 

[scooby84 10+ year member]

Thank you Ecrack. I have another question. The way both subs are wired currently is at 2ohms separately. They are in a box, but the box separates the two sides, and both subs are wired independently. They are 4ohm DVC subs. So, if both subs are wired to 2ohms, and I connect both positives in the positive terminal and the same for the negatives, what impedance will they run at? I have it in my mind that 2ohm plus 2ohm will equal 4ohms, but I'm fairly new to the concepts. I have looked at wiring diagrams and tried to learn as much about impedance before asking these questions though.

 

[FenixAudio 10+ year member]

there are two ways to wire subs...series and parallel. then you wire 2 4ohm vc's in paraelle like you have them your DIVIDE the resistance in half. when you wire in series you DOUBLE the impedance.

thus an amp at 4ohms will run say 500watts, an amp at 2 ohms will try and run 1000watts if it can be wired to 2 ohms. @ 1 ohm it goes to 2000w @.5ohms 4000 watts and on and on and on. every time you divide your resistance you double your power abilities only if the amp can thermally work at that low of an ohm load.

 

[ahole-ic]

Thank you Ecrack. I have another question. The way both subs are wired currently is at 2ohms separately. They are in a box, but the box separates the two sides, and both subs are wired independently. They are 4ohm DVC subs. So, if both subs are wired to 2ohms, and I connect both positives in the positive terminal and the same for the negatives, what impedance will they run at? I have it in my mind that 2ohm plus 2ohm will equal 4ohms, but I'm fairly new to the concepts. I have looked at wiring diagrams and tried to learn as much about impedance before asking these questions though.

If you connect + to +, then they become 1 ohm because they are in parallel. If you wire them in series, they will be at 4 ohm. What is the difference you may ask?

In a circuit, the electricity enters from one terminal, goes through the coil and exits the other terminal and returns to the amplifier to complete the circuit. With two woofers in parallel, the electricity comes from the amplifier and enters both of the + terminals of the two woofers at the same time and exits both terminals of the - at the same time. Since this provided two pathways, the resistance is half. Let me rephrase that so you'll understand what it means. If you have two 4" pieces of pvc, and you connect them to a source of water, you can get twice the amount of water through them as you could 1. This means that resistance on the water flow has been cut in half.

In series, it is like you took those two pieces of pvc and connected them end to end. You restricted your waterflow.

So what happens here? The postive of one woofer is connected to the amplifier. The negative from that woofer is connected to the positive of the other woofer. The negative of that second woofer is then connected to the amplifier. What you have done is caused the electricity to pass through one coil and then the other before returning to the amplifier. This is series wiring and doubles the impedence.

 

[scooby84 10+ year member]

So basically you're telling me that if I have two 4ohm DVC subs, both separately wired to 2ohms like I have now, if I connect them both to the amp that i explained above, which would then make them wired in parallel, they would be running at 2ohms. I posted a few weeks ago and someone told me that it was impossible to wire two 4ohm DVC subs to 2ohms. Or am I just completely confused?

 

[ahole-ic]

So basically you're telling me that if I have two 4ohm DVC subs, both separately wired to 2ohms like I have now, if I connect them both to the amp that i explained above, which would then make them wired in parallel, they would be running at 2ohms. I posted a few weeks ago and someone told me that it was impossible to wire two 4ohm DVC subs to 2ohms. Or am I just completely confused?

You're confused. They would not be wired at 2 ohms. That is impossible. They would be wired at 1 or 4 ohms.