Understanding series/parallel help please

[Bun-Bun 10+ year member]

In the case of your example there, it wouldn't matter at all and I'd buy whichever one was produced and suited my need. You can actually prove mathematically that the T/S parameters of a sub don't change when the coils are wired in series or parallel. Power distribution between the coils is the same either way as well. The only difference is the load presented to the amp.
Plenty of companies make D1 subs, BTW.

D4 sub wired in parallel to 200w (easy math) would be 20v 10A total or 20v and 5A per coil.

D1 wired in series would be 20V 10A total, 10V 10A per coil.

When on the same former, connected to the same cone and getting the same signal, the coils of a sub, regardless of how many there are act as a single coil. Wiring them in series or parallel only changes the load to the amp. There are some trick that you can play powering only one of hte coils, but those are best left ot people who know exactly what they're doing and are trying to achieve a specific result.

Ok so two SVC subs in the same scenario as above. Each sub would see less current and theoretically the coils would run cooler and have less impedance rise... not?

But in the previous example the coils would still run cooler not? They are running on a higher voltage with less current.

 

[ultimate157 5,000+ posts]

Ok so two SVC subs in the same scenario as above. Each sub would see less current and theoretically the coils would run cooler and have less impedance rise... not?
But in the previous example the coils would still run cooler not? They are running on a higher voltage with less current.

(2) SVC 4 ohm with 200w in parallel would be 100w per coil, 20v @ 5a.

Now put them in series. 200w into 8 ohms is 5A and 10v per coil.

 

[Bun-Bun 10+ year member]

(2) SVC 4 ohm with 200w in parallel would be 100w per coil, 20v @ 5a.
Now put them in series. 200w into 8 ohms is 5A and 10v per coil.

Missed my point. 2 SVC 4 ohms vs 2 SVC 1 ohm both wired to 2 ohm.

The 2 SVC 4 ohms in parrallel would be less curent through the coils (5A as opposed to 10A). identicle to the example before just two SVC instead of one DVC. That elliminates his coil acting as one argument.

 

[ultimate157 5,000+ posts]

Missed my point. 2 SVC 4 ohms vs 2 SVC 1 ohm both wired to 2 ohm.
The 2 SVC 4 ohms in parrallel would be less curent through the coils (5A as opposed to 10A). identicle to the example before just two SVC instead of one DVC. That elliminates his coil acting as one argument.

Yes, in that situation there would be less total current, but there are very few cases that will actually result in that conclusion. You really don't have to worry about coil configuration and wiring unless you are worried about heating up your coils by running quite a bit more RMS than recommended.

 

[Bun-Bun 10+ year member]

Yes, in that situation there would be less total current, but there are very few cases that will actually result in that conclusion. You really don't have to worry about coil configuration and wiring unless you are worried about heating up your coils by running quite a bit more RMS than recommended.

Exactly! ok I'm good now. lol

 

[lvjeffro 10+ year member]

http://www.bcae1.com ...great place for info

 

[helotaxi 5,000+ posts]

Missed my point. 2 SVC 4 ohms vs 2 SVC 1 ohm both wired to 2 ohm.
The 2 SVC 4 ohms in parrallel would be less curent through the coils (5A as opposed to 10A). identicle to the example before just two SVC instead of one DVC. That elliminates his coil acting as one argument.

The current isn't an A/B comparison because you are comparing different loads. The wattage into each is the same and heat is expressed in watts. There is no difference in coil heating because the actual heat is the same.

Quit worrying about it. There isn't a difference.

 

[Bun-Bun 10+ year member]

The current isn't an A/B comparison because you are comparing different loads. The wattage into each is the same and heat is expressed in watts. There is no difference in coil heating because the actual heat is the same.
Quit worrying about it. There isn't a difference.

*edit* Misread your post originally

Now my brain has gone way off track again. Basic thermo. energy into a system = energy out of a system. And heat can be expressed in watts. But if you take two runs of cable and put the same power to it but one with a lower voltage and the other with the higher voltage, you would have the first one with a higher current and the second with a lower current. The one with the lower current would be less restricted and generate less heat accross that line. This technique is used in our mains power. The power lines run at a significantly higher voltage to reduce voltage drop and heat loss (i beleive) accross long runs of power lines and then transform it down to the 110v (actually 220 two phase but yeah) that we use. Its like friction... more current = more friction = more heat loss.

Power lost = Current^2 * resistance. Thus less current will result in less heat lost at the coils and more power to the woofer, cooler coils, and less impedance rise. Overall better, not?

However as ultimate said very few situations would result in this scenario as once you get into DVC and the simple fact that I dont know anyone who would buy 1 ohm subs and wire to 2 ohm... in practice the combinations just don't exist as my above example. Just some theory I am playing around with cause that's what I do =D

 

[Buck 5,000+ posts]

this has to be one of these easiest things to understand

 

[Bun-Bun 10+ year member]

this has to be one of these easiest things to understand

It should be but helotaxi had to come along and confuse it... I am just making sure =D

 

[helotaxi 5,000+ posts]

*edit* Misread your post originally
Now my brain has gone way off track again. Basic thermo. energy into a system = energy out of a system. And heat can be expressed in watts. But if you take two runs of cable and put the same power to it but one with a lower voltage and the other with the higher voltage, you would have the first one with a higher current and the second with a lower current. The one with the lower current would be less restricted and generate less heat accross that line. This technique is used in our mains power. The power lines run at a significantly higher voltage to reduce voltage drop and heat loss (i beleive) accross long runs of power lines and then transform it down to the 110v (actually 220 two phase but yeah) that we use. Its like friction... more current = more friction = more heat loss.

Power lost = Current^2 * resistance. Thus less current will result in less heat lost at the coils and more power to the woofer, cooler coils, and less impedance rise. Overall better, not?

However as ultimate said very few situations would result in this scenario as once you get into DVC and the simple fact that I dont know anyone who would buy 1 ohm subs and wire to 2 ohm... in practice the combinations just don't exist as my above example. Just some theory I am playing around with cause that's what I do =D

Once again you've missed/neglected Ohm's law. You can't apply different voltages to two wires of the same resistance and get the same power through each. The voltage determines the current and the current multiplied by the voltage is the power lost.

Regardless of how the whole thing is wired up, if you have two subs wired to the same final impedance on identical amps they will both see the same amount of power and they will need to shed the same amount of heat. The same amount of voltage is applied to each driver, inducing the same current and thus dropping the same amount of power. It IS really easy to understand, and I haven't confused the topic at all, you just haven't put the pieces together.

Think about it. P=I^2 * R. If you have a lower resistance/impedance, you can run more current for the same power loss. Current isn't the only variable like you're treating it. You're tying to change only one of the variables and keep the result the same, it doesn't work that way. Yes there would be more current through each coil with a D1 sub wired in series vs a D4 in parallel, but because of the lower impedance, the you can run more current for the same power, change one variable and you have to change the other to keep result constant which we've stated is the case.

 

[Bun-Bun 10+ year member]

Once again you've missed/neglected Ohm's law. You can't apply different voltages to two wires of the same resistance and get the same power through each. The voltage determines the current and the current multiplied by the voltage is the power lost.
Regardless of how the whole thing is wired up, if you have two subs wired to the same final impedance on identical amps they will both see the same amount of power and they will need to shed the same amount of heat. The same amount of voltage is applied to each driver, inducing the same current and thus dropping the same amount of power. It IS really easy to understand, and I haven't confused the topic at all, you just haven't put the pieces together.

Think about it. P=I^2 * R. If you have a lower resistance/impedance, you can run more current for the same power loss. Current isn't the only variable like you're treating it. You're tying to change only one of the variables and keep the result the same, it doesn't work that way. Yes there would be more current through each coil with a D1 sub wired in series vs a D4 in parallel, but because of the lower impedance, the you can run more current for the same power, change one variable and you have to change the other to keep result constant which we've stated is the case.

That makes no sense... the voltage to each driver will change depending on how it is wired....

I havent been only changing one variable... I have been changing variables appropriate to the situation. ohm's law I=V/R and W=IV. Therefore 10V at 10A is 100W while 20V at 5A is 100W. two different wirings coming to the same power. Now P=I^2 * R will be less given the 20v 5A scenario meaning more power gets to the destination then the 10v 10A situation. I know this true because this is how they do it for our mains power! They run mains power at a higher voltage for less power loss accross all of our power lines and then have transformers near our homes that step it down to 220 2 phase (110 single phase) for use in our homes.

Thus less current through coils would equate to less power loss to heat. So in the situation I described this is true.

2 x 4ohm subs wired in parallel to 200w would be 20v 10A total or 20v and 5A per coil.

2 x 1ohm subs wired in series would be 20V 10A total, 10V 10A per coil.

EDIT:

wait I think I just noticed what you were saying...

EDIT2:

Yup I did. The power loss in both of those wiring scenario's is 100W.

 

[helotaxi 5,000+ posts]

wait I think I just noticed what you were saying...
EDIT2:

Yup I did. The power loss in both of those wiring scenario's is 100W.

Exactly. More current only means more power lost if the load remains constant. Since we're talking about different loads, more current doesn't mean more power.

Ohms law is really simple.

 

[ultimate157 5,000+ posts]

The current isn't an A/B comparison because you are comparing different loads. The wattage into each is the same and heat is expressed in watts. There is no difference in coil heating because the actual heat is the same.

See, thats exactly what I thought until someone told me a while back that the current determines the heat, which I was //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif about. I can't remember who told me that though.

 

[Bun-Bun 10+ year member]

See, thats exactly what I thought until someone told me a while back that the current determines the heat, which I was //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif about. I can't remember who told me that though.

Well that statement alone is false as you can have more/less heat with the same amount of watts in but it would have to be a radiaclly different amp design or a different power source (which wouldn't exist anyway which I guess makes my post moot)