Power rating of the AMP ?

[Raymond_Hu]

guys, can anyone teach me how to get approximate the RMS value of the AMP? I ask a few acc. shop they just tell me how many amp PMPO, but when I ask how much is the RMS but nobody know.... any idea guys?

 

[mnkh0027]

guys, can anyone teach me how to get approximate the RMS value of the AMP? I ask a few acc. shop they just tell me how many amp PMPO, but when I ask how much is the RMS but nobody know.... any idea guys?

Look at the manual RMS, continous power, nominal power ratings. Skip the MAX and PMPO ratings. Buy something reputable where you can contact the manufacturer to clarify (ie. by email) or at least visit the company's website.

 

[Bert]

Look at fuse rating...

(fuse)*6/# of channels= RMS/channel

This is a very rough estimate and is about correct for a class AB amp.

So for a 4 channel amp with fuse rating of 50A it will come to 75w/channel...

note: As I said, this is a very rough guide. It may differ based on the efficiency of the amp as well as the design.

 

[cacin]

Look at fuse rating...

(fuse)*6/# of channels= RMS/channel

This is a very rough estimate and is about correct for a class AB amp.

So for a 4 channel amp with fuse rating of 50A it will come to 75w/channel...

note: As I said, this is a very rough guide. It may differ based on the efficiency of the amp as well as the design.

Class AB amps efficiency is normally around 50%. Unless u get the really good ones :D

 

[pillage2001]

Class AB amps efficiency is normally around 50%. Unless u get the really good ones :D

What about Class D amps?

 

[Bert]

Class D is from 60-80%... but they play limited frequencies and if you put a good AB amp at those freq, it could outperform a Class D

 

[lby]

hi there,
i'm also quite blur about the RMS value,anyone can help me look at this?what is the RMS value of this amp?I'm quite new in ICE,does this brand produce good amps?hardly see it at market.

http://www.banleongbros.com/rodek/rodex_sm7540.htm

thanks guys.

 

[Zenn]

around 65W x 4, based on 40A fuse rating @ 13V and 50% efficiency.

 

[BryanCheng]

then wat is the different for 12V and 14.4V? is that means when our car with the engine running and the battery will produce 14.4v? and when the engine not running and the batt will produce 12v???

 

[cacin]

then wat is the different for 12V and 14.4V? is that means when our car with the engine running and the battery will produce 14.4v? and when the engine not running and the batt will produce 12v???

A normal car battery will produce 12V. When you are running the engine, the power is not supplied by the battery. It actually come from the alternator. When your engine is running, the battery becomes a load for the electrical system. When you turn of the engine, power is supplied by your battery. I am not really sure the 14.4V comes from where though.

 

[lby]

thanks for your information,can this amp able to support a 10inch sub?

65W x 4 can i bridge 2 channel and support the sub,then others 2 channel support the front and back mid?

anyone heard about this brand before?Rodek?does it is a good amplifier?i'm quite new about the ice,hope anyone can help me.thanks.

 

[[email protected]]

1000pmpo = 15 rms

 

[Zenn]

thanks for your information,can this amp able to support a 10inch sub?

65W x 4 can i bridge 2 channel and support the sub,then others 2 channel support the front and back mid?

anyone heard about this brand before?Rodek?does it is a good amplifier?i'm quite new about the ice,hope anyone can help me.thanks.

should be able to run bridged for sub and the other two running the fronts, but not both front & rear. although u can wire them in parallel and drop the impedance to 2 ohms, which they claim is stable, but i would advise against it. risky with heat & distortion

sorry never heard of the brand......

 

[lby]

thanks Zenn,

now i got another question.currenty get a amp from my fren,i think is chap ayam brand,since i'm quite new in ICE,on the amp they state 2X400W,and there are run by two 30amp fuse.can i know wat is the rms value?how do i know that is the amp is bridgeable?i just use it to run a 10inch sub at the back,it does build in crossover,so i can adjust the bass and treble.does it have any problem?

i don not have front speaker,so i wired the amp input from the front speaker signal,but the sound like not very good,any wrong with my wiring?do i need to get a cross over to set the signal that is lower that 90Hz?hope any sifu can help so.thanks again...

 

[Zenn]

60A fuse is around 200W x 2, bridged probly be 400W pretty good for sub amp. if u cant get the manual or cant find the specs on the net, just be safe and bridge it mono at 4ohms. also since u said theres a inbuilt crossover on the amp why not use that.

 

[lby]

ok thanks Zenn,

can i know how to bridge it to mono at 4ohms?how to wire??is it like the below?

L+ -----Sub+
L-
R+
R- ------Sub-

crossover is it that it can adjust the treble and the bass?

there is a switch that can switch between Sub or Nor, so i should switch it to Sub rite?

thanks to clear my doubt...

 

[Bert]

The wiring is correct for most amps while the crossover is wrong.. hehe

A crossover is to limit the frequencies beingplayed by a speaker. LP is to play everythign below X hz and Hp is to play everythign above X hz...

I would say put the switch at Sub.. most likely it has a built in x-over at a preset freq.

 

[lby]

thanks...

I'll try again...