does the amplifier divide power.......

[Beatin' 10+ year member]

.......between multiple subs?

This has been bothering me for a while.

If the amp is giving lets say, 200wrms at 4 ohms to two subs, do both subs get 200wrms or do they each get 100wrms?

Does it matter if the subs are wired in parallel or series, etc?

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[goingdef 10+ year member]

There each getting 100, series or parallel doesn't matter each sub will see a division of the amps total rms output.

 

[quackhead 10+ year member]

.......between multiple subs?
This has been bothering for a while.

If the amp is giving lets say' date=' 200wrms at 4 ohms to two subs, do both subs get 200wrms or do they each get 100wrms?

Does it matter if the subs are wired in parallel or series, etc?[/quote']

are you wiring two 4 ohm subs or two subs that present a final impedance of 4 ohms? Power applied to the final impedance will be divided among the number of subs used.

 

[mat3833 10+ year member]

fun fact: if you have 2 subs, one rated for say 500W rms and another only rated for 250W RMS and they are Dual Voice Coil you can wire the "higher" powered one to a lower ohm load and it will receive more power. not reccomended, because its really easy to mess up final load calcs and you can blow ur amp among other things, but it can be useful(at least in my experiance it has been)

Matt

 

[quackhead 10+ year member]

fun fact: If you have 2 subs, one rated for say 500w rms and another only rated for 250w rms and they are dual voice coil you can wire the "higher" powered one to a lower ohm load and it will receive more power. Not reccomended, because its really easy to mess up final load calcs and you can blow ur amp among other things, but it can be useful(at least in my experiance it has been)
matt

huh?

 

[gckless 5,000+ posts]

fun fact: if you have 2 subs, one rated for say 500W rms and another only rated for 250W RMS and they are Dual Voice Coil you can wire the "higher" powered one to a lower ohm load and it will receive more power. not reccomended, because its really easy to mess up final load calcs and you can blow ur amp among other things, but it can be useful(at least in my experiance it has been)
Matt

I'm pretty sure you are incorrect. The amp only sees a final resistance, and does not care how many subs there are. Unless that's a two channel amp, and each sub was on a different channel. But in that case, this is irrelevant in relation to the OP's question.

 

[mat3833 10+ year member]

lol, im actually right. yes, the amp "sees" a ohm load. but = A+B since electricity will always choose the path of least resistance the sub with the lowest "ohm load" will receive more power than the higher load one. ill see if i can dig up an old website that had a calculator just for this type of thing. its more of a home theater thing. not really applicable in a car, but when you have 3 subs in 3 different types of enclosures all playing a specific frequency range it comes in handy if u dont have a single amp for each.

for example if you have 2 D4 subs. wire one of them to 2 ohms and the other to 8 ohms. if ur amp pushes 500W in theory the 2 ohm sub will get ~400W while the 8 ohm sub will only get ~100W. granted ur final ohm load will be something like 1.6 ohms, but when u throw in series and parallel wireing configurations you can come close to a 1,2,or 4 ohm load.'

since 8 ohms is 4 times the resistance of 2 ohms, the 8 ohm woofer will get ~4 times less power. its Ohms law at its finest. oh and ohms law is Current = Voltage/resistance.

Matt

EDIT: http://speakerimpedance.co.uk/?act=two_parallel&page=calculator here is one calculator. not quite as shiny as the one i used to use. but still the same deal.

Edit #2 http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmlaw.html elecrtical law link. decent read if you have the time.

 

[gckless 5,000+ posts]

lol, im actually right. yes, the amp "sees" a ohm load. but = A+B since electricity will always choose the path of least resistance the sub with the lowest "ohm load" will receive more power than the higher load one. ill see if i can dig up an old website that had a calculator just for this type of thing. its more of a home theater thing. not really applicable in a car, but when you have 3 subs in 3 different types of enclosures all playing a specific frequency range it comes in handy if u dont have a single amp for each.
for example if you have 2 D4 subs. wire one of them to 2 ohms and the other to 8 ohms. if ur amp pushes 500W in theory the 2 ohm sub will get ~400W while the 8 ohm sub will only get ~100W. granted ur final ohm load will be something like 1.6 ohms, but when u throw in series and parallel wireing configurations you can come close to a 1,2,or 4 ohm load.

Matt

EDIT: Speaker Impedance here is one calculator. not quite as shiny as the one i used to use. but still the same deal.

Ok, I could see that in parallel wiring. I would think it would not work in series though. In any case, I would think OP should not look into that, if he needs to be asking this question. Bad results will follow.

 

[mat3833 10+ year member]

fair enough. but it applies both parallel and series. anyways, sorry to get so off track.

Matt

 

[quackhead 10+ year member]

lol, im actually right. yes, the amp "sees" a ohm load. but = A+B since electricity will always choose the path of least resistance the sub with the lowest "ohm load" will receive more power than the higher load one. ill see if i can dig up an old website that had a calculator just for this type of thing. its more of a home theater thing. not really applicable in a car, but when you have 3 subs in 3 different types of enclosures all playing a specific frequency range it comes in handy if u dont have a single amp for each.
for example if you have 2 D4 subs. wire one of them to 2 ohms and the other to 8 ohms. if ur amp pushes 500W in theory the 2 ohm sub will get ~400W while the 8 ohm sub will only get ~100W. granted ur final ohm load will be something like 1.6 ohms, but when u throw in series and parallel wireing configurations you can come close to a 1,2,or 4 ohm load.'

since 8 ohms is 4 times the resistance of 2 ohms, the 8 ohm woofer will get ~4 times less power. its Ohms law at its finest. oh and ohms law is Current = Voltage/resistance.

Matt

EDIT: Speaker Impedance here is one calculator. not quite as shiny as the one i used to use. but still the same deal.

Edit #2 Ohm's Law elecrtical law link. decent read if you have the time.

No, you specifically stated using subs with different power ratings will receive different wattages....and to clarify, what about phase issues involving the use of different subs wired to different impedance in the same environment?

 

[mat3833 10+ year member]

re-read my first post. i only used the "RMS" figure to help make my point. i stated you can wire the higher powered sub to a lower ohm load to receive more power and vice versa. you could wire the "lower RMS" sub to a lower load and blow it if u wanted to. and when i did something like this i had 4 subs total at the time. i had 2 6.5" subs in Tapped horns, 1 10" sub in a sealed box, and a 15" sub in a really low tuned ported box. basicly the 6.5s played midbass and down to ~90hz, the sealed 10 played~90hz to ~35hz, and the ported 15 played 35hz and below. the crossover network was a pain in the ***, but total system power was only ~1K watts and it sounded **** good.

and the phasing was basicly a non issue due to the crossover settup. there was some slight cancelation at each crossover point but a sinple EQ boost fixed that problem.

Matt

 

[gckless 5,000+ posts]

re-read my first post. i only used the "RMS" figure to help make my point. i stated you can wire the higher powered sub to a lower ohm load to receive more power and vice versa. you could wire the "lower RMS" sub to a lower load and blow it if u wanted to. and when i did something like this i had 4 subs total at the time. i had 2 6.5" subs in Tapped horns, 1 10" sub in a sealed box, and a 15" sub in a really low tuned ported box. basicly the 6.5s played midbass and down to ~90hz, the sealed 10 played~90hz to ~35hz, and the ported 15 played 35hz and below. the crossover network was a pain in the ***, but total system power was only ~1K watts and it sounded **** good.
and the phasing was basicly a non issue due to the crossover settup. there was some slight cancelation at each crossover point but a sinple EQ boost fixed that problem.

Matt

But OP will not be using crossovers, and both woofers will be playing the same frequencies. Issues. In your example, yes it could be useful with a bunch of equipment OP doesn't have. But I think it was bad judgement to bring up given the OP's knowledge level on the subject.

 

[mat3833 10+ year member]

you are correct, it may be useful information, but it was un-nessecary in this case.

Matt