ohm question for speakers
06-17-2003, 09:11 PM
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ohm question for speakers
I've heard a lot about ohms, but haven't taken that semester of physics yet and I want to know if ohms apply to regular speakers too. Meaning not subs. I have a pair of 6x9 JL TR-690 TX's, and I wanted to know what ohm load they need. I found no specs on the box, or online. Can they work at 2 ohms?
The reason I ask, is because I am thinking about getting the kicker kx700.5 amp, and it is much more powerful for the sub at 2 ohms, but I don't know if I can run the sub at 2 ohms and the speakers at 4ohms.
If this sounds confusing, I'm sorry, but any info would be helpful.
The reason I ask, is because I am thinking about getting the kicker kx700.5 amp, and it is much more powerful for the sub at 2 ohms, but I don't know if I can run the sub at 2 ohms and the speakers at 4ohms.
If this sounds confusing, I'm sorry, but any info would be helpful.
06-17-2003, 09:13 PM
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Oh by the way, I haven't purchased front speakers yet (probably going to get 6.5" JL's to match) and I don't yet have a sub (probably going to get a 10" or 12" don't know what until i get the amp)
06-18-2003, 03:32 AM
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car speakers are manufactured at 4 ohms... so the amp will operate at 4ohms per channel...
I'm guessing thats a 5 channel amp... running the sub at 2 ohms is fine, you will still be able to use the other 4 channels at 4 ohms each.
I'm guessing thats a 5 channel amp... running the sub at 2 ohms is fine, you will still be able to use the other 4 channels at 4 ohms each.
06-18-2003, 04:39 AM
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Yo
you cant change the ohm value of a speaker you can only change the what the amp see's as resistance in ohms.
run 2 4 ohm speakers in series = 8 ohm load, run 2 4 ohm speakers in parallel = 2 ohm load
every speaker is stamped somewhere showing the ohm value
a 2 ohm speaker needs lots of power to run it
great speakers can handle lots of power and be effecient as well
look for the most effecient as possible, this way your speaker will be loud without using all your power, youll have more reserve for highs and lows
you cant change the ohm value of a speaker you can only change the what the amp see's as resistance in ohms.
run 2 4 ohm speakers in series = 8 ohm load, run 2 4 ohm speakers in parallel = 2 ohm load
every speaker is stamped somewhere showing the ohm value
a 2 ohm speaker needs lots of power to run it
great speakers can handle lots of power and be effecient as well
look for the most effecient as possible, this way your speaker will be loud without using all your power, youll have more reserve for highs and lows
06-18-2003, 11:08 AM
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A few things to keep in mind:
1. A driver's impedance changes across it's bandwidth....meaning as frequency changes, so does the actual load.
2. The enclosure also has an affect
3. Amplifiers simply "see" the load and react accordingly - not the other way around.
4. Generally, speakers are listed according to their nominal load - the lowest resistance that you will find when using it under normal operating conditions.
This is correct, but don't make the mistake of averaging or dividing the loads to try to determine the final load, here are the proper equations where Rf is the final impedance of wiring i drivers:
For series:
Rf = R1 + R2 + R3 + ... + Ri
For parallel:
(1/Rf) = (1/R1 ) + (1/R2) + (1/R3) + ... + (1/Ri)
FALSE! A speakers coil configuration has nothing to do with it's inherent efficiency. While there are some minor changes to a driver's T/S parameters based on coil config, this is not an absolute measure of a driver's efficiency.
If you are running a pair of 2 ohm components, you acutually can run a SMALLER amp then you would if they were 4 ohm components.
That statement is almost like saying black cars are faster then blue ones....there is no real correlation.
Simply put a 2 ohm driver can extract more power from your amp then a 4 ohm driver, keeping all else equal.
I would never shop for a speaker on efficiency alone. Efficiency can be measured in MANY different ways under many different conditions. It's very hard to compare one efficiencies across manufacturers. Efficiencies are important for those who want to use a pair of co-ax off of a head unit, past that, shop with your ears, not by some numbers printed on a piece of paper.
1. A driver's impedance changes across it's bandwidth....meaning as frequency changes, so does the actual load.
2. The enclosure also has an affect
3. Amplifiers simply "see" the load and react accordingly - not the other way around.
4. Generally, speakers are listed according to their nominal load - the lowest resistance that you will find when using it under normal operating conditions.
Originally posted by jrich
run 2 4 ohm speakers in series = 8 ohm load, run 2 4 ohm speakers in parallel = 2 ohm load
run 2 4 ohm speakers in series = 8 ohm load, run 2 4 ohm speakers in parallel = 2 ohm load
For series:
Rf = R1 + R2 + R3 + ... + Ri
For parallel:
(1/Rf) = (1/R1 ) + (1/R2) + (1/R3) + ... + (1/Ri)
a 2 ohm speaker needs lots of power to run it
If you are running a pair of 2 ohm components, you acutually can run a SMALLER amp then you would if they were 4 ohm components.
That statement is almost like saying black cars are faster then blue ones....there is no real correlation.
Simply put a 2 ohm driver can extract more power from your amp then a 4 ohm driver, keeping all else equal.
look for the most effecient as possible, this way your speaker will be loud without using all your power, youll have more reserve for highs and lows
06-18-2003, 11:31 PM
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hey thanks everyone especially rcurley55. So I can run my 4 speakers at 4 ohms, and run the channel for the sub at 2 ohms? assuming I buy a 2 ohm sub.
And also if I decide to buy two extra speakers in the front (six total) how would I divide amp power if it is 4 channels? or would I just run 2 speakers off the deck and 4 off the amp? I don't know enough about amps or speakers at this time which is why I ask the simple questions.
And also if I decide to buy two extra speakers in the front (six total) how would I divide amp power if it is 4 channels? or would I just run 2 speakers off the deck and 4 off the amp? I don't know enough about amps or speakers at this time which is why I ask the simple questions.
06-19-2003, 03:06 AM
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so ure gonna run the rears first b4 having the front speakers??
wow...ur soundstage will b quite horrible...
if u do happen to get another set of speakers...the front..
my suggestion is to get something better than the rear speakers..
those will b the main speakers u listen to..
power them with ur amp <channel 1 &2>
and use the other channels <bridge 3&4> for ur sub
wow...ur soundstage will b quite horrible...
if u do happen to get another set of speakers...the front..
my suggestion is to get something better than the rear speakers..
those will b the main speakers u listen to..
power them with ur amp <channel 1 &2>
and use the other channels <bridge 3&4> for ur sub
06-19-2003, 06:32 PM
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Less is more.....
Get a set of components for the front, run the 6x9's in the rear, and get a sub that presents a 2 ohm load (i.e. a single voice coil 2 ohm sub, or a sub with dual 4 ohm coils).
Get a set of components for the front, run the 6x9's in the rear, and get a sub that presents a 2 ohm load (i.e. a single voice coil 2 ohm sub, or a sub with dual 4 ohm coils).
06-20-2003, 12:12 AM
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Originally posted by rcurley55
Less is more.....
Get a set of components for the front, run the 6x9's in the rear, and get a sub that presents a 2 ohm load (i.e. a single voice coil 2 ohm sub, or a sub with dual 4 ohm coils).
Less is more.....
Get a set of components for the front, run the 6x9's in the rear, and get a sub that presents a 2 ohm load (i.e. a single voice coil 2 ohm sub, or a sub with dual 4 ohm coils).
ok, about components, I've been looking around and noticed that most component speakers come with a tweeter (so a 6.5" and a tweeter) Is this what I need to buy for the front? Or are there a lot of component speakers that are just the 6.5".
I'm going to keep going to my local audio dealers to listen to some speakers, and if I find any that sound good I will post to see if they are good or not.
Also with an amp...if the power output is about 50W RMS to each channel and my speakers want 60W RMS, is it good enough, cause I noticed that with my deck running about 22-27W (don't know actual amount) per channel, they sound decent. I'm wondering if 50W would be enough to satisfy the speakers. And if I have a set of components in the front and 6x9's in the rear and the RMS power is different for each of them, what kind of power supply do I want to give them? (Assuming the components have 50W RMS, and the 6x9's are 60W)
If you reply, thanks for answering any of my questions
06-22-2003, 10:09 PM
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rcurley
where do you get off
you can,t defy the laws of physics
ever heard of ohms law? next your going to say that shorting out the speaker wires won't put load the amp because its 0 ohms.
or gee wiss my amp sure runs hot ,duh maybe im using a lot of power to run those 2 ohm subs, sure the damn things louder but think of it, more power less efficiency/ and maybe you should research the term DYNAMIC HEADROOM.
hey man the kid asking the ?'s needs to find out if the amp he's buying is 2 ohm stable first, and hell, get a 1 ohm stable amp and then get a dual voice coil sub stick it in a box and run it in parallel.
also watch out for seperates, and the immaging of them. sometimes the placement sucks or the crossovers are crap.
i've always felt that buying speakers from manufacturers that primarily only make speakers sound better, ie:infinity, kef, boston, bose, etc. but again it's a personal thing. buy what you like to hear not some salemans idea
more later
kid my advice to you is go to your local stereo dealer for advice but dont take it as god/ flag over someone with a great sounding setup ask ?'s/ go to a sound off comp. have fun doin it and lastly never buy cheap speakers. protect them with a good clean power amp with a lot of DYNAMIC HEADROOM: and a good crossover never hurt.
where do you get off
you can,t defy the laws of physics
ever heard of ohms law? next your going to say that shorting out the speaker wires won't put load the amp because its 0 ohms.
or gee wiss my amp sure runs hot ,duh maybe im using a lot of power to run those 2 ohm subs, sure the damn things louder but think of it, more power less efficiency/ and maybe you should research the term DYNAMIC HEADROOM.
hey man the kid asking the ?'s needs to find out if the amp he's buying is 2 ohm stable first, and hell, get a 1 ohm stable amp and then get a dual voice coil sub stick it in a box and run it in parallel.
also watch out for seperates, and the immaging of them. sometimes the placement sucks or the crossovers are crap.
i've always felt that buying speakers from manufacturers that primarily only make speakers sound better, ie:infinity, kef, boston, bose, etc. but again it's a personal thing. buy what you like to hear not some salemans idea
more later
kid my advice to you is go to your local stereo dealer for advice but dont take it as god/ flag over someone with a great sounding setup ask ?'s/ go to a sound off comp. have fun doin it and lastly never buy cheap speakers. protect them with a good clean power amp with a lot of DYNAMIC HEADROOM: and a good crossover never hurt.