what sounds better/louder?
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what sounds better/louder?
does it sound better/hit harder to have 1 sub hooked up to an amp bridged or to have 2 subs hooked up to 2 channles? i have one alpine type X hooked up to a kenwood KAC-9152D bridged and it sounds good but doesnt hit like i thought it would. if i added another type X and ran two channles would it hit harder?
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From: Nine-Zero-Nine
i think that you have a crappy system, no offense. i personally am going with a 400 watt amp bridged to a 600watt sub. the amp is going to be a kicker, and the sub will be a kicker L7.. hits like nothing else
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From: SJ408-KC816-KS913
you can acatully have both subs hooked up bridged....bridge the amp right then when you run the wire to the subs run the + to the right sub and run the - to the left speaker or it vise versa.. then get one small lenght wire and put it in the middle ...so that it runs from - to + ....its called in parelel or series one of thiose cant remmeber sorry ..try that and see what hapens...
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From: City of Champs, MA
Originally Posted by 05_camo_boxb
you can acatully have both subs hooked up bridged....bridge the amp right then when you run the wire to the subs run the + to the right sub and run the - to the left speaker or it vise versa.. then get one small lenght wire and put it in the middle ...so that it runs from - to + ....its called in parelel or series one of thiose cant remmeber sorry ..try that and see what hapens...
and as far as blackonblacktc, keep your stupid comments to yourself. How are you even thinking of powering an L7 with only 400 watts, bridged nonetheless. If you can even afford an L7, then you can at least get a good enough amp with enough power.
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From: City of Champs, MA
And as far as answering the initial question, look at the specs for both the subs and the amp. Try to match the Rec. RMS from the sub to the RMS output from the amp. That should make your sub sound to the best of its abilities and if it doesnt hit hard enough, then look at either upgrading your subs or amp. I know I went from 2 10" Pioneers to 1 12" Polk and I felt that the 2 10"s hit harder but the 1 12" sounds cleaner. im planning to get another 12" Polk but the amp I have wont be capable of powering another sub so Im looking at getting a good Class D Mono Amp. Take a look at Elemental Design Audio stuff, they make some good equipment at a good price. I know that I regret not going for a full eDesigns system in my tC
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From: SJ408-KC816-KS913
he dont have a crappy system...how is alpine or kenwood crap...and as far as you say 400 watts shehs good luck ..my bro had 2 1,000 watt amps to each L7..now that was insane....is my sytem crap to cause i have a new kenwood deck ,with a kenwood 1,000 watt amp to a 1 12 inch rockford fos in a speced rockford fos sealed box??ive seen lots of samll systems blow away larger systems casue of proper specs....and sorry forgot about the ohms thing havent done stereo stuff in a while...
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hey guys...thanks for putting blackonblacktc in his place. that was kinda an a_hole thing to say. oh well...he dont know what hes talking about.
the reason i ask this question is because i have my sub running at 2 ohms bridged. the amp i have runs 900 watts rms at 2 ohms and its a class D amp. and it seems to me that a sub that handles 1000 watts rms should hit a lot harder with a full 900 rms going to it. oh well.
is there a way to run 2 subs bridged so that they both get the full load of the amp going to them? both my amp and sub are stable at 2 ohms.
the reason i ask this question is because i have my sub running at 2 ohms bridged. the amp i have runs 900 watts rms at 2 ohms and its a class D amp. and it seems to me that a sub that handles 1000 watts rms should hit a lot harder with a full 900 rms going to it. oh well.
is there a way to run 2 subs bridged so that they both get the full load of the amp going to them? both my amp and sub are stable at 2 ohms.
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Every amplifier is designed to deliver FULL power at a specifically rated impedence load. It is up to the user to choose subwoofers with the proper impedences to get the power out of an amp. If an amp is rated 500watts @ 4 ohms and you have an 8 ohm load, the amp will only deliver 250watts. Likewise, If you take the same amp and put a 2 ohm load on it, the amp will TRY to deliver 1000watts and burn up! It's the power supply that dictates what it's limits are. Bridging 2 channel amps or using single channel 'monoblock' amps are no different. Some monoblock amps are 2-channel amps bridged internally.
And don't forget that big amps NEED big power. It's not magic, it's physics. It takes approximately 13 amps of currant @ 12 volts to produce 100 watts. No ifs ands or buts! OK that means that your 1000 watt amp needs 130 amps of currant to make full power. Typical Hondas are lucky if they have a 60 amp alternator. That amp will never see 1000 watts.
Again it's not magic, it's physics! Want to know what the REAL rating of an amp is? Look at the amount of fusing on the amp. A manufacturer will never fuse it's amp above it's rated capability. Take what you see and multiply by 13. Or for ease say 10 amps. An amp with 60 amps of fusing will probably deliver 600watts of true power. But be careful! Some manufacturers try to trick you by putting in 'dumby' fuses.
Also a very important factor often overlooked is the speakers' efficiency. Usually rated in dB's @ 1 watt 1 meter. Or how many decibles of output a speaker has when driven with 1 watt of power measured with a microphone 1 meter away.
Typically, your cheaper/entry level type sub is more efficient then a monster sub because of the mass of a heavy duty suspension of those type of subs. In otherwords, given the SAME amount of power, a more efficient sub will play louder then a monster sub. The difference is the monster sub is capable of handling more power and will have a greater output with more power. Thats why bigger isn't always better unless your upgrading everything.
Now for the wiring part!
There is 3 ways to wire multiple sub woofers.
Parallel Wiring:
When wiring multiple subs and/or voice coils together, you connect the positive of one coil to the positive of the other coil and the negative to the negative.
When parallel wiring, the impedences halve(for 2 subs). ie; 2 - 8ohm subs paralleled together = 4 ohms ... 2 - 4 ohm subs paralleled = 2 ohms. If you have a dual voice coil sub, it's the same as having 2 sub woofers. If you parallel the 2 voice coils together you will halve the impedence. Sooo if you have 2 dual voice coil subs rated at 4 ohms each coil paralled together, you would have an end result of 1 ohm. 2 - 4 ohm voice coils paralleled make each sub a 2 ohm impedence, then 2 - 2 ohm subs paralleled together = 1 ohm.
Series Wiring:
When wiring multiple subs and/or voice coils together, you connect the positive of the amp to the positive terminal of the first coil, then connect the negative of the 1st coil to the positive of the 2nd coil, then the negative of the 2nd coil to the negative of the amplifier.
When series wiring, the impedences add. ie; 2 - 4 ohm subs series'd together = 8 ohms. 2 - 2 ohm subs series'd together = 4 ohms. etc.
Comb'd parallel and series:
Used most commonly to wire 2 dual voice coil subs together when tring to arrive at a specific impedence on the amplifier. Wiring the dual voice coil of each sub in 'series' then 'paralleling' the 2 subs together. ie; First 'series' the 2 coils of each sub by connenting one wire between the negative terminal of one coil to the positive terminal of the 2nd coil. Then take the positive of the first coil and the negative of the 2nd coil and 'parallel' the 2 subs together . Positive to positive - negative to negative.
I'll post a picture that will help understand if that was confusing.
Last and certainly not least is the subwoofer's recommended enclosure air space. Too often I see people put subs in the wrong size box and go "man this crap sucks! I'll never buy brand x's subs again they suck" When all along theynever gave it a chance to work properly.
I hope that clarifies some things.
And don't forget that big amps NEED big power. It's not magic, it's physics. It takes approximately 13 amps of currant @ 12 volts to produce 100 watts. No ifs ands or buts! OK that means that your 1000 watt amp needs 130 amps of currant to make full power. Typical Hondas are lucky if they have a 60 amp alternator. That amp will never see 1000 watts.
Again it's not magic, it's physics! Want to know what the REAL rating of an amp is? Look at the amount of fusing on the amp. A manufacturer will never fuse it's amp above it's rated capability. Take what you see and multiply by 13. Or for ease say 10 amps. An amp with 60 amps of fusing will probably deliver 600watts of true power. But be careful! Some manufacturers try to trick you by putting in 'dumby' fuses.
Also a very important factor often overlooked is the speakers' efficiency. Usually rated in dB's @ 1 watt 1 meter. Or how many decibles of output a speaker has when driven with 1 watt of power measured with a microphone 1 meter away.
Typically, your cheaper/entry level type sub is more efficient then a monster sub because of the mass of a heavy duty suspension of those type of subs. In otherwords, given the SAME amount of power, a more efficient sub will play louder then a monster sub. The difference is the monster sub is capable of handling more power and will have a greater output with more power. Thats why bigger isn't always better unless your upgrading everything.
Now for the wiring part!
There is 3 ways to wire multiple sub woofers.
Parallel Wiring:
When wiring multiple subs and/or voice coils together, you connect the positive of one coil to the positive of the other coil and the negative to the negative.
When parallel wiring, the impedences halve(for 2 subs). ie; 2 - 8ohm subs paralleled together = 4 ohms ... 2 - 4 ohm subs paralleled = 2 ohms. If you have a dual voice coil sub, it's the same as having 2 sub woofers. If you parallel the 2 voice coils together you will halve the impedence. Sooo if you have 2 dual voice coil subs rated at 4 ohms each coil paralled together, you would have an end result of 1 ohm. 2 - 4 ohm voice coils paralleled make each sub a 2 ohm impedence, then 2 - 2 ohm subs paralleled together = 1 ohm.
Series Wiring:
When wiring multiple subs and/or voice coils together, you connect the positive of the amp to the positive terminal of the first coil, then connect the negative of the 1st coil to the positive of the 2nd coil, then the negative of the 2nd coil to the negative of the amplifier.
When series wiring, the impedences add. ie; 2 - 4 ohm subs series'd together = 8 ohms. 2 - 2 ohm subs series'd together = 4 ohms. etc.
Comb'd parallel and series:
Used most commonly to wire 2 dual voice coil subs together when tring to arrive at a specific impedence on the amplifier. Wiring the dual voice coil of each sub in 'series' then 'paralleling' the 2 subs together. ie; First 'series' the 2 coils of each sub by connenting one wire between the negative terminal of one coil to the positive terminal of the 2nd coil. Then take the positive of the first coil and the negative of the 2nd coil and 'parallel' the 2 subs together . Positive to positive - negative to negative.
I'll post a picture that will help understand if that was confusing.
Last and certainly not least is the subwoofer's recommended enclosure air space. Too often I see people put subs in the wrong size box and go "man this crap sucks! I'll never buy brand x's subs again they suck" When all along theynever gave it a chance to work properly.
I hope that clarifies some things.
and yes like i said about the speced box ive seen 10 's blow 12 's away..cause done right ..
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From: varies
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i say change amps.... i have never had goodluck with kenwood amps at all.. i had a 700 watt kenwood pushing two memphis 10's and then i switched to a kicker 400 watt sx series amp and it was like i added 5 pairs of subs in the back...
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What is the impedance on the subs?
nm...all Type X's are D4's
Well, your amp will do 900x1 at 1 ohm or 900x1 at 2 ohms...realistically you'll get about the same power with one sub as you would a pair.
In the real world, a pair of subs on the same power will be louder as you won't encounter power compression as quickly(I'm honestly not sure if a Type X would exhibit any compression under 900 watts...they're damn beefy subs).
With one wired up, you'd want to do this:
With a pair you'd do this:
Honestly...I don't think the increase in output you'll see will be worth an extra Type X...unless you get an extra amp/bigger amp too.
nm...all Type X's are D4's
Well, your amp will do 900x1 at 1 ohm or 900x1 at 2 ohms...realistically you'll get about the same power with one sub as you would a pair.
In the real world, a pair of subs on the same power will be louder as you won't encounter power compression as quickly(I'm honestly not sure if a Type X would exhibit any compression under 900 watts...they're damn beefy subs).
With one wired up, you'd want to do this:
With a pair you'd do this:
Honestly...I don't think the increase in output you'll see will be worth an extra Type X...unless you get an extra amp/bigger amp too.
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Good info here, but some needs clarification.. first about amps. A 1000 watt amp will not need 130 amps 99.9999% of the time because it will NOT produce 1000 watts rms Here is why:
Most amps are rated at peak power and say so. So if it is rated 1000 watts, it is not producing 1000 watts rms. The rms value is going to give you the effective DC value you will be running.
To make it even more fun, most amps are rated using a pure sine wave. You will never see a pure sine wave in an audio waveform. So the rating is not practical, but is a good standard for reference.
Now, some amps rate different ways and some more expensive amps have more accurate numbers.
Now, onto bridging and the electrical terms:
An amplifier final stage delivers the most efficient power when impedance matching is met. Basically, this means that going lower on your load impedance (your speakers) does not necessarilly mean you will provide more power to the speakers. So follow the reccomendation on the amps.
To describe impedance, keep in mind that a speakers impedance is not static. Impedance is a reactive resistance. This means it includes the effects of the coils inductive reactance and capacitive reactance. Reactance is the resistance to AC current flow and changes with frequency. This will not mean as much to you when designing your system, but is nice to know since they specify impedance rather than resistance.
To figure your speakers impedance when more than one is involved on one channel:
Parallel impedance = 1/(1/L1 + 1/L2 + ..... + 1/LN) where the L is the load, or speaker. For two speakers that are matched in impedance in parallel, simply cut the impedance in half. To illustrate this using the formula for 2 4 ohm speakers in parallel:
1/(1/4ohms + 1/4ohms) = 1/(1/2) = 2 ohms.
For impedances in series simply add them up.
When you think about power, keep in mind that power in always equals power out. So if you are producing 300 watts of true power out of your amp, you are using 300 watts of power from your charging system (while running, your alternator WILL have to produce this regardless of battery or caps). Out of your amp to your speakers, you are providing higher voltage and lower current, which is why you dont have to have enormous speaker cables. On the power input side, you are providing approx 14.4 volts and enough current to create the 300 watts, which is about 21 amps neglecting efficiency of the amp. Taking efficiency into account you are safer figuring somewhere around 10 - 12 amps per 100 watts as mentioned previously. This is because 300 watts to the speakers means some power is lost in the amp. For reference, Class D amps are VERY efficient, which is why they are smaller. All that heat you produce from an amp is the wasted power.
Hopefully this helps a little
**************EDIT******************
Thought I would clarify that last part a bit. If an amp is truly pushing 300 watts TO THE SPEAKER then there is still some power that is being wasted over and above that. So you will still be providing the amp with more than 300 watts
Most amps are rated at peak power and say so. So if it is rated 1000 watts, it is not producing 1000 watts rms. The rms value is going to give you the effective DC value you will be running.
To make it even more fun, most amps are rated using a pure sine wave. You will never see a pure sine wave in an audio waveform. So the rating is not practical, but is a good standard for reference.
Now, some amps rate different ways and some more expensive amps have more accurate numbers.
Now, onto bridging and the electrical terms:
An amplifier final stage delivers the most efficient power when impedance matching is met. Basically, this means that going lower on your load impedance (your speakers) does not necessarilly mean you will provide more power to the speakers. So follow the reccomendation on the amps.
To describe impedance, keep in mind that a speakers impedance is not static. Impedance is a reactive resistance. This means it includes the effects of the coils inductive reactance and capacitive reactance. Reactance is the resistance to AC current flow and changes with frequency. This will not mean as much to you when designing your system, but is nice to know since they specify impedance rather than resistance.
To figure your speakers impedance when more than one is involved on one channel:
Parallel impedance = 1/(1/L1 + 1/L2 + ..... + 1/LN) where the L is the load, or speaker. For two speakers that are matched in impedance in parallel, simply cut the impedance in half. To illustrate this using the formula for 2 4 ohm speakers in parallel:
1/(1/4ohms + 1/4ohms) = 1/(1/2) = 2 ohms.
For impedances in series simply add them up.
When you think about power, keep in mind that power in always equals power out. So if you are producing 300 watts of true power out of your amp, you are using 300 watts of power from your charging system (while running, your alternator WILL have to produce this regardless of battery or caps). Out of your amp to your speakers, you are providing higher voltage and lower current, which is why you dont have to have enormous speaker cables. On the power input side, you are providing approx 14.4 volts and enough current to create the 300 watts, which is about 21 amps neglecting efficiency of the amp. Taking efficiency into account you are safer figuring somewhere around 10 - 12 amps per 100 watts as mentioned previously. This is because 300 watts to the speakers means some power is lost in the amp. For reference, Class D amps are VERY efficient, which is why they are smaller. All that heat you produce from an amp is the wasted power.
Hopefully this helps a little
**************EDIT******************
Thought I would clarify that last part a bit. If an amp is truly pushing 300 watts TO THE SPEAKER then there is still some power that is being wasted over and above that. So you will still be providing the amp with more than 300 watts
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^^ the box has everything to do with the sound of the sub.....It's very important that with sealed boxes, the internal loaded volume of the enclosure be within requirement of the sub.... also, in order to have a correctly built and tuned ported enclosure, you have to design and build it to the thiele small parameters of the particular sub the enclosure will house...