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Discussion Starter · #1 ·
Esteemed Bretheren, I am still in process of attaining materials for my tapped horn tuba sub, so in the meantime I'm using my 12" kicker 10c124 I'm a 1 cubic foot ported box tuned to 23 hz. The driver is capabable of 150w rms and is 4 ohms.

Now. My front left and right a 8 ohm nominal speakers. The reciver(pioneer vsx 524 k) can put out 140 watts at 6 ohms and 80 watts at 8 ohm per channel.

I've hooked my my kicker directly to the front right speaker output.

Now for the question. since I do not have a subwoofer amp and I have connected the speaker to the reciever I have set subwoofer to no and front speakers to large. Will this action send lfe to the front left and right mains?

Initially I had my cross over set at 80hz. But noticed that the sub did not dig very low. So i changed the front crossover to 50 hz and notice it does dig a nice bit deeper.

But now I have arrived at a more technical question since the imedance of the 2 speakers connected at the amp makes the amp out put more power, correct? How much percent of the power should be diverted to the 4 ohm load and how much power should be diverted to the 8 ohm load.
 

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But now I have arrived at a more technical question since the imedance of the 2 speakers connected at the amp makes the amp out put more power, correct? How much percent of the power should be diverted to the 4 ohm load and how much power should be diverted to the 8 ohm load.
Roughly speaking:

If the amp is delivering 3 watts, 2W will be dissipated in the 4 ohm load and 1W will be dissipated in the 8 ohm load.
 

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Discussion Starter · #3 · (Edited)
Roughly speaking:

If the amp is delivering 3 watts, 2W will be dissipated in the 4 ohm load and 1W will be dissipated in the 8 ohm load.
Ok. Then roughly speaking..... if the amps put out 3 watts at 6 ohm. The they should put out 2 watts at 8 ohms?
 

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Ok. Then roughly speaking..... if the amps put out 3 watts at 6 ohm. The they should put out 2 watts at 8 ohms?
http://www.ohmslawcalculator.com/ohms-law-calculator

two different questions, if I recall my high school electronics correctly.

First, what is total power at any given voltage [think of it as volume control setting] into different impedances? This seems to be your second question.

Second, in a circuit with multiple speakers of different impedances, how will power be dissipated between the higher and lower impedance devices. This seems to be your first question.

The answer is different depending on which question you are asking. If you don't know which question you are asking, the answer is, find out which question you are asking . . . .

3 watts is 4.24 volts at six ohms. that 4.24 volts at 8 ohms will yield 2.25 watts. If voltage remains constant, doubling the resistance cuts power in half, so cutting the resistance, logically and actually, doubles power. And a less than doubling of the resistance must, therefore, do something less than cut power in half.

a six ohm and 8 ohm speaker present an impedance of about 3.4 ohms, in in parallel, and 12 ohms if in series. http://www.speakerimpedance.co.uk/?act=two_parallel&page=calculator
 

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Discussion Starter · #5 · (Edited)
http://www.ohmslawcalculator.com/ohms-law-calculator

two different questions, if I recall my high school electronics correctly.

First, what is total power at any given voltage [think of it as volume control setting] into different impedances? This seems to be your second question.

Second, in a circuit with multiple speakers of different impedances, how will power be dissipated between the higher and lower impedance devices. This seems to be your first question.

The answer is different depending on which question you are asking. If you don't know which question you are asking, the answer is, find out which question you are asking . . . .

3 watts is 4.24 volts at six ohms. that 4.24 volts at 8 ohms will yield 2.25 watts. If voltage remains constant, doubling the resistance cuts power in half, so cutting the resistance, logically and actually, doubles power. And a less than doubling of the resistance must, therefore, do something less than cut power in half.

a six ohm and 8 ohm speaker present an impedance of about 3.4 ohms, in in parallel, and 12 ohms if in series. http://www.speakerimpedance.co.uk/?act=two_parallel&page=calculator
Yes I like the way you understand things. Finally someone else that thinks like me!!!!

Ok. The channel is rated at 80 watts from 20-20k hz into a 6 ohm load. I I'm trying to figure out the math between how many watts the sub draws away from the main and how much I need to boost it so that the left and right are equal again. I would figure this out myself with my spl meter however there is a paradox. I cannot accurately measure the response of the main whilst the sub is active because it puts out far to many db's. And I cannot measure the speaker without the additional load because it would receive more watts.
 

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If you are trying to set a powered sub, it will do what it does. Not a lot of reason to fret over it. pink noise is used because it kind of is like the power distribution of real sound. About equal power in each octave. So the octave from 40-80 Hz will be equalish in power to the octave from 80 to 160 Hz. Each doubling of frequency is one octave. Music mostly has significant content from 40Hz to 20000 Hz. about 9 octaves. If you can multiply and divide by two you can rough it out yourself. The amp feeding the mains will not have to make the power needed for the frequencies covered by the sub, if the sub is self powered. That's a third question, not the same as either of the first two questions you apparently did not intend to ask. Not knowing enough to ask what you want to know does not make the folks who answer the questions you actually asked unhelpful.
 

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Discussion Starter · #7 · (Edited)
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