Ohms?
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Ohms?
I recently purchased a set of Alpine SPS-600c speakers. They come with two components and two tweeters. Alpine suggest I run the tweeters off of the components. I'm planning on pushing these with a four channel amp.
What I would like to know is: with the component being 4 ohms and the tweeter running off of it, does the tweeter drop it to 2 ohms if I put that on channel one on my amp or can I run another component and tweeter on the same channel to make it drop to 2 ohms?
What I would like to know is: with the component being 4 ohms and the tweeter running off of it, does the tweeter drop it to 2 ohms if I put that on channel one on my amp or can I run another component and tweeter on the same channel to make it drop to 2 ohms?
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You pain in the ***, Yuli 
OP, What amp are you using? Do you even have a crossover point high enough to cross the tweeter over seperately/actively? Or are you leaving Alpine's capacitor in place? With what it seems that you are describing, you're using all 4 channels to power the 2 pairs of drivers (aka 4 speakers), therefore the individual impedance of the drivers is going to be what the amp "sees". If you meter the drivers individually, you'll get a better idea what load they are going to present
OP, What amp are you using? Do you even have a crossover point high enough to cross the tweeter over seperately/actively? Or are you leaving Alpine's capacitor in place? With what it seems that you are describing, you're using all 4 channels to power the 2 pairs of drivers (aka 4 speakers), therefore the individual impedance of the drivers is going to be what the amp "sees". If you meter the drivers individually, you'll get a better idea what load they are going to present
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Thread Starter
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I'm using the Alpine MRP-F300 amp to power four door speakers that also happen to be Alpine: For the front will be the SPS-600c and for the back is the SPS-600.
I want to run the amp at 2 ohms to bring it to 75 watts per channel. The speakers can handle 80 watts RMS.
I want to run the amp at 2 ohms to bring it to 75 watts per channel. The speakers can handle 80 watts RMS.
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Related noob question.
Hey,
I'm a noob to all this and was wondering something along the same lines but a bit different.
I am buying 2 sets of components (polk audio SR5250), one for the front and one for the back and was planning on running them off of an Arc Audio 4-channel amp.
One set of SR5250's comes with two 5 1/4 inch drivers, two 1 inch tweeters and two crossovers. I'm assuming that the driver and tweeter are wired into the crossover and split a single channel from the amp, so I could run front and back components off only 4 channels even though there are 8 speakers, yes?
The rms per side on the 5250's is 100 watts, with a 200W peak. The arc audio amp is putting out 80 watts rms per channel at 4 ohms, 160 watts rms per channel at 2 ohms.
1.) Is this enough power for the components?
2.) Can this be wired at 2 ohms to take advantage of the extra wattage?
2a.) If yes, will it overpower the components?
2b.) If no, why offer the 2 ohm rating?
3.) Do the crossovers just overlap frequencies or do they distribute the wattage too (ex. 50 watts to the driver and 30 watts to the tweeter)?
4.) Would there be any point in running each set of components off their own 4-channel amp so each speaker is getting maximum available wattage?
4a.) If yes, how would this be wired (with the crossover, etc)?
I'm having trouble visulaizing how exactly all this plays out. All I know is that the SR5250's (from reading reviews) are super clean and smooth so I want to maximize the power going to them so I can really crank the whole thing up!
Without blowing them of course.
Your thoughts on all this are greatly appreciated. Thank you.
-Ryan
I'm a noob to all this and was wondering something along the same lines but a bit different.
I am buying 2 sets of components (polk audio SR5250), one for the front and one for the back and was planning on running them off of an Arc Audio 4-channel amp.
One set of SR5250's comes with two 5 1/4 inch drivers, two 1 inch tweeters and two crossovers. I'm assuming that the driver and tweeter are wired into the crossover and split a single channel from the amp, so I could run front and back components off only 4 channels even though there are 8 speakers, yes?
The rms per side on the 5250's is 100 watts, with a 200W peak. The arc audio amp is putting out 80 watts rms per channel at 4 ohms, 160 watts rms per channel at 2 ohms.
1.) Is this enough power for the components?
2.) Can this be wired at 2 ohms to take advantage of the extra wattage?
2a.) If yes, will it overpower the components?
2b.) If no, why offer the 2 ohm rating?
3.) Do the crossovers just overlap frequencies or do they distribute the wattage too (ex. 50 watts to the driver and 30 watts to the tweeter)?
4.) Would there be any point in running each set of components off their own 4-channel amp so each speaker is getting maximum available wattage?
4a.) If yes, how would this be wired (with the crossover, etc)?
I'm having trouble visulaizing how exactly all this plays out. All I know is that the SR5250's (from reading reviews) are super clean and smooth so I want to maximize the power going to them so I can really crank the whole thing up!
Without blowing them of course.
Your thoughts on all this are greatly appreciated. Thank you.
-Ryan
Last edited by SocialMisfit; Oct 19, 2010 at 06:41 PM.
Good questions:
Weather you buy coaxial 2 ways or component 2 way and you use the supplied crossover, You are only connecting the 2 wires of the crossover to your amp. The amp sees the 4 ohms.
so the answers to
1.) Is this enough power for the components?
Yes it is. More power would do no harm.
2.) Can this be wired at 2 ohms to take advantage of the extra wattage?
>NO
2a.) If yes, will it overpower the components?
2b.) If no, why offer the 2 ohm rating?
>You could wire 2 sets of speakers in parallel. This is rare.
3.) Do the crossovers just overlap frequencies or do they distribute the wattage too (ex. 50 watts to the driver and 30 watts to the tweeter)?
> Power is distributed across the frequency spectrum. There are graphs for speaker design that show how much power goes to the bass, the mid, and the tweeter depending on the crossover frequencies . But for our discussion there is more power in lower frequencies than in the higher frequencies. That is why woofer voicecoils are huge and tweeter voicecoils are tiny. I would estimate that for a typical crossover frequency of 3500Hz, that less than 10% of the power is going to the tweeters. It will vary with the kind of music. Especially power to subwoofers.
4.) Would there be any point in running each set of components off their own 4-channel amp so each speaker is getting maximum available wattage?
>Do you mean the 2 front midwoofers and the 2 front tweeters have each their own channel of a 4 channel amp? Yes this is called bi amping and has a great advantage and can be done 2 ways: If your crossovers can be divided so that the mid and high section are independant and you can connect to separate channels. MUCH better is to use an electronic crossover BEFORE the amplifyer so that you separate the frequencies before the amp. You then dont have to use crossovers. But some manufactureres recommend using crossovers anyway, but independantly low and high. This is getting complicated. My setup is electronic crossovers. I have 100watts (the RF 200A4 bridged) for each mid and 50 watts (from 2 of the channels the RF600A5)for each tweeter up front. My rears are diven from the other 2 channels of the RF600A5. The loudness will cause serious hearing loss.
Alternatively, if your amp allows it, you can bridge 4 channels into 2 for more power.
4a.) If yes, how would this be wired (with the crossover, etc)?
> you must see if your crossover can be separated into 2 independant sections so you can connect to 2 amps independantly. Read your installation manual.
On a separate note lets not get too caught up with impedance. When they say 4 ohms this is only nominal and approximate and at a very select freqeuncy range. The real impedance will vary from 2 to maybe over 20 ohms at higher frequencies.
Also the rear speakers are for ambiance fill, unless you often have rear passengers that like it loud.
for a very good discussion of bi amping, amp distortion etc
http://sound.westhost.com/articles.htm
Hope this helps
Weather you buy coaxial 2 ways or component 2 way and you use the supplied crossover, You are only connecting the 2 wires of the crossover to your amp. The amp sees the 4 ohms.
so the answers to
1.) Is this enough power for the components?
Yes it is. More power would do no harm.
2.) Can this be wired at 2 ohms to take advantage of the extra wattage?
>NO
2a.) If yes, will it overpower the components?
2b.) If no, why offer the 2 ohm rating?
>You could wire 2 sets of speakers in parallel. This is rare.
3.) Do the crossovers just overlap frequencies or do they distribute the wattage too (ex. 50 watts to the driver and 30 watts to the tweeter)?
> Power is distributed across the frequency spectrum. There are graphs for speaker design that show how much power goes to the bass, the mid, and the tweeter depending on the crossover frequencies . But for our discussion there is more power in lower frequencies than in the higher frequencies. That is why woofer voicecoils are huge and tweeter voicecoils are tiny. I would estimate that for a typical crossover frequency of 3500Hz, that less than 10% of the power is going to the tweeters. It will vary with the kind of music. Especially power to subwoofers.
4.) Would there be any point in running each set of components off their own 4-channel amp so each speaker is getting maximum available wattage?
>Do you mean the 2 front midwoofers and the 2 front tweeters have each their own channel of a 4 channel amp? Yes this is called bi amping and has a great advantage and can be done 2 ways: If your crossovers can be divided so that the mid and high section are independant and you can connect to separate channels. MUCH better is to use an electronic crossover BEFORE the amplifyer so that you separate the frequencies before the amp. You then dont have to use crossovers. But some manufactureres recommend using crossovers anyway, but independantly low and high. This is getting complicated. My setup is electronic crossovers. I have 100watts (the RF 200A4 bridged) for each mid and 50 watts (from 2 of the channels the RF600A5)for each tweeter up front. My rears are diven from the other 2 channels of the RF600A5. The loudness will cause serious hearing loss.
Alternatively, if your amp allows it, you can bridge 4 channels into 2 for more power.
4a.) If yes, how would this be wired (with the crossover, etc)?
> you must see if your crossover can be separated into 2 independant sections so you can connect to 2 amps independantly. Read your installation manual.
On a separate note lets not get too caught up with impedance. When they say 4 ohms this is only nominal and approximate and at a very select freqeuncy range. The real impedance will vary from 2 to maybe over 20 ohms at higher frequencies.
Also the rear speakers are for ambiance fill, unless you often have rear passengers that like it loud.
for a very good discussion of bi amping, amp distortion etc
http://sound.westhost.com/articles.htm
Hope this helps
Last edited by zoomer; Oct 19, 2010 at 09:03 PM.
Thread Starter
0 Watt CAFz'r
Joined: Oct 2010
Posts: 7
Good questions:
Weather you buy coaxial 2 ways or component 2 way and you use the supplied crossover, You are only connecting the 2 wires of the crossover to your amp. The amp sees the 4 ohms.
so the answers to
1.) Is this enough power for the components?
Yes it is. More power would do no harm.
2.) Can this be wired at 2 ohms to take advantage of the extra wattage?
>NO
Weather you buy coaxial 2 ways or component 2 way and you use the supplied crossover, You are only connecting the 2 wires of the crossover to your amp. The amp sees the 4 ohms.
so the answers to
1.) Is this enough power for the components?
Yes it is. More power would do no harm.
2.) Can this be wired at 2 ohms to take advantage of the extra wattage?
>NO
I was under the impression that if you hook up 2 speakers to 1 channel on say a four channel amp that is capable at running at 4 ohms and 2 ohms. It will drop down to 2 ohms on the channel that has two speakers on it.
If this is not the case.. please tell me how to get my amp to run at 2 ohms because I want the 75 watts per channel not 50 watts per channel seeing my speakers can handle 80 watts rms.
