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Its it any different between class AB and D amplifier for 12'' subwoofer. What is the pros and cons?

My subwoofer provide 250w RMS, should I get a 4 channel amp use 2 ch bridged(220w rms) at 4 ohm or get a monoblock with 250w rms at 4 ohm output. Which is better, if get 4channel amplifier, I still can use for 2 channel more.

Which is better way for subwoofer, class AB or D amp and bridged 2 channel output or monoblock?
 

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At that's power level it is a wash.
At high power, even I would go Class-D.

So if you have an amp already, or find a cheap used one, then there should be a few at those power levels... in either Class-AB or D.
But if you are buying a the new Class-D makes sense, and probably somewhat higher power also makes sense.

Note: I have a 300W ([email protected]) Class-AB as a sub amp.
 

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Discussion Starter #3
At that's power level it is a wash.
At high power, even I would go Class-D.

So if you have an amp already, or find a cheap used one, then there should be a few at those power levels... in either Class-AB or D.
But if you are buying a the new Class-D makes sense, and probably somewhat higher power also makes sense.

Note: I have a 300W ([email protected]) Class-AB as a sub amp.
that mean for class D monoblock for subwoofer is more powerfull and reliable
 

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Class D is more friendly on your electrical system at higher power but if I was only looking to provide 250-300 watts as you're intending to do then an A/b amp would do just fine.
 

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Discussion Starter #5
Class D is more friendly on your electrical system at higher power but if I was only looking to provide 250-300 watts as you're intending to do then an A/b amp would do just fine.
I have a 4 ch amp but will use for 2 way front stage, I think I will go for class D monoblock for trunk subwoofer
 

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Discussion Starter #6
One more questions, I saw some person load 4ohm to 2ohm and get high watt for subwoofer. What is the different betweem 4ohm and 2ohm
 

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2ohm speakers have lower resistance than 4ohm speakers, so they draw more power from the amp. That's normally a good thing, especially for subs, but only if the amp can handle the ohm load. There a lots of different ways to wire subwoofers, and each will affect the ohm load at the amp.
 

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2ohm speakers have lower resistance than 4ohm speakers, so they draw more power from the amp. That's normally a good thing, especially for subs, but only if the amp can handle the ohm load. There a lots of different ways to wire subwoofers, and each will affect the ohm load at the amp.
This is the spec of amp that I plan to buy, how good is the subwoofer when running 2ohm
 

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What subwoofer is it? You can't simply pick and choose if you want 4 ohms or 2 ohms, it will depend on the number of voice coils, and their impedance.
 

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that mean for class D monoblock for subwoofer is more powerfull and reliable
^Assuming there should be a question mark at the end?^

A 300w Class-AB is more puwerful than a 250W Class-D.
A 1000w Class-D would be more powerful than a 300w Class-A.

A content arguement for reliability can be made for a 15 year old Class-AB that works.

If you are headed to a new amp, then I would be looking at 500-1kW class-D

If you only need 250W, and have an existing amp or willing to get a used amp, then Class-AB makes sense. I would think a few people have lower power sub amps for sale?

This is the spec of amp that I plan to buy, how good is the subwoofer when running 2ohm
That will make 400w into 2-ohms and 200w into 4-ohms...
And then at 4-ohms, the old 300w Class-AB has Personally I would rather have a 2x 4-ohm VC wired in parallel to 2-ohms... or run a 4-ohm sub.
But does it matter?
 

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I think this is getting too complicated for a simple question. I don't think he cares about the sonic differences between Class AB and Class D.

Generally speaking, a Class D monoblock is the best choice for subs. If u have enough space in your vehicle, get 2 4ohm subs and wire them for a 2ohm load. That's how my system is set up. If u only want to run 1 sub, then get a DVC sub with 4ohm coils. The coils can then be wired to create a 2ohm load.
 

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As people have said, class D is more power efficient, which means it won’t waste as much electricity as heat like a class A/B will. And class D can be smaller while still putting out good power.

But 250w is a small amp for a subwoofer, which is why it doesn’t matter much whether you go with class A/B or D.

if you were to get a high excursion subwoofer (>20mm) then I’d suggest more power but for a subwoofer under 20mm, 250w is a little low but should work fine.
 

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How about this.. If you decide to go with a 2 ohm load get a Class D. If you go with a 4-ohm final load get a Ab amplifier.
 

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Discussion Starter #15
^Assuming there should be a question mark at the end?^

A 300w Class-AB is more puwerful than a 250W Class-D.
A 1000w Class-D would be more powerful than a 300w Class-A.

A content arguement for reliability can be made for a 15 year old Class-AB that works.

If you are headed to a new amp, then I would be looking at 500-1kW class-D

If you only need 250W, and have an existing amp or willing to get a used amp, then Class-AB makes sense. I would think a few people have lower power sub amps for sale?



That will make 400w into 2-ohms and 200w into 4-ohms...
And then at 4-ohms, the old 300w Class-AB has Personally I would rather have a 2x 4-ohm VC wired in parallel to 2-ohms... or run a 4-ohm sub.
But does it matter?
I didnt know my specs of subwoofer since I was keep for more than 5 year, but I thinks it was 200-300w rms at 4ohm.
I have a 4 channel AB amp for my front stage with 4x70rms, 2x220 bridged @4ohm.

Btw, what is the different between 4ohm and 2ohm, it is good? How to hook up
 

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I think this is getting too complicated for a simple question. I don't think he cares about the sonic differences between Class AB and Class D.

Generally speaking, a Class D monoblock is the best choice for subs. If u have enough space in your vehicle, get 2 4ohm subs and wire them for a 2ohm load. That's how my system is set up. If u only want to run 1 sub, then get a DVC sub with 4ohm coils. The coils can then be wired to create a 2ohm load.
Ya, I want to run one sub only. Which is the best way for I run it and how it hook up
 

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mohawk classic mc.124
Looks like that is a dual 4 ohm sub with dual voicecoil. You have two options for wiring it if that is indeed the correct configuration; 2 ohms or 8 ohms. If those are the choices, definitely wire it to 2 ohms. Look at Crutchfield subwoofer wiring diagrams to get the proper way to wire your sub to the amp.
 

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Is it 2ohm sound will be better?
How are you defining better?
Loudness?
Distortion?
Something else?

They should about the in 1, 2 or 4 ohm.
Inthoery 4 or 8'ohm could sound better, but theory says it is still almost nothing one can hear.
 

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Discussion Starter #20
How are you defining better?
Loudness?
Distortion?
Something else?

They should about the in 1, 2 or 4 ohm.
Inthoery 4 or 8'ohm could sound better, but theory says it is still almost nothing one can hear.
bass beat could be more deep, because I notice that when put a single sub in trunk at a sedan car, normally will listen bass is slow from rear
 
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