whats Total System Power & total RMS power?

[penguin1]

http://us.creative.com/products/product.asp?category=4&subcategory=25&product=10596&nav=technicalSpecifications

so.. which one of the two is the power consumption of the system?

 

[misry]

RMS is root meaning squared and always refers to AC power, (or audio sine waves in this case). 120 Volts AC is an RMS value.

Total watts includes the wattage dropped by the power supply itself.

These values are referencing the power coming from the wall socket and can be thought of as the total power that is converted to heat by a system.

In the example you provide it looks like the power supply itself drops a good chunk of watts.

 

[DaveUK]

RMS (root mean squared I think it is, or something like that) is the real important figure when it comes to guaging the power (or raw volume) of hifi gear.

'Total System Power', to be honest, I'm not sure - perhaps it is the power consumption in W such as you say as it is drawn from the socket (counting for a less than 100% efficient amplifier of course). Some of the power gets lost in heat.

The other figure you often here is PMPO (Peak mean power output I *think*, again off the top of my head) which is often an overly exaggerated and altogether useless figure.

In short, the only figure you need to judge the relative volume of the system is the RMS figure.

Bear in mind that the subwoofer will normally have a much higher RMS rating than the satellites, due to the way subwoofers work within a far more limited frequency range I presume.

To be perfectly honest, that system would be fine in terms of volume for surround gaming and movies at lowish volumes. If it's power or loud music listening that you are after, then you really should be aiming for something like the G500, or the Z-5400/5500 from logitech.

 

[HoldenMcGroin]

RMS is root meaning squared and always refers to AC power, (or audio sine waves in this case). 120 Volts AC is an RMS value.

Close, but no cigar.

120 Volts is the AC value, NOT RMS value.

120 VAC * .707 = 84.84 VRMS.

RMS

These values are referencing the power coming from the wall socket and can be thought of as the total power that is converted to heat by a system.

It does reference the power coming from the socket, but it is a not an automatic reference to heat conversion. Only a small amount of power is lost as heat, the rest is converted to a useful output of a device, unless that device is a toaster, then I am wrong. See HERE.

 

[penguin1]

eh.... i think thats to diffcult for me to understand.

Actually all i wanted to know is how much power this: http://us.creative.com/products/product.asp?category=4&subcategory=25&product=10596&nav=technicalSpecifications consumes. becasue eletrical bills are very high here.. i'm very concern abt the power intake of this speaker which i am kinda attracted to.

because power is measured in watts, and that link gives two,
72 watts total RMS power
&
115 Watts Total System Power

so which one represents power intake? someone PLEASE help!

 

[ctrob]

Well, given that the output can't be more than the input - it's clear that power intake is 115W.

72W is the total RMS sound output. 115W is the total (RMS) electrical power input, which is what you pay for.

However, this is the capacity of the system and I doubt you'll run it at anything like this. I used to have a 30W RMS/channel stero (60W RMS) at college and had the porters visit cos someone had complained that the music in the party room (nearby) was too loud! I'm surprised at how low the audio output of most products is these days - often sub 10W. So you're probably just buying headroom to avoid distortion on the loudest moments.

The reason they say RMS is that it was (is?) a marketing ploy to add up the RMS channel power and then double it to give a "Peak Music Power Output" PMPO to make their product look better.

 

[penguin1]

thx. erm.. Am i also right to say that 115W is the maximum input? and the 5.1 system will hardly ever really take in that amount (like lower vol, bass) ?

 

[crualtortus]

thx. erm.. Am i also right to say that 115W is the maximum input? and the 5.1 system will hardly ever really take in that amount (like lower vol, bass) ?

it will most likely never use 115w. that is the max power out put. it is the highest the system is capable of, which could only last a few secounds. so no, its not going to output that much power. your electric bill isnt going to go up.. much :twisted:

 

[penguin1]

oh ok thats great.. 72W is for maximum sound ouput and 115W is maximum power intake from the mains..

thanks guys! btw, don't u think that speaker looks cool? I like simple stuff so i dun think i'm for those 5.1 with fancy cruvy designs.

 

[cyprod]

RMS is root meaning squared and always refers to AC power, (or audio sine waves in this case). 120 Volts AC is an RMS value.

Close, but no cigar.

120 Volts is the AC value, NOT RMS value.

120 VAC * .707 = 84.84 VRMS.

RMS

These values are referencing the power coming from the wall socket and can be thought of as the total power that is converted to heat by a system.

It does reference the power coming from the socket, but it is a not an automatic reference to heat conversion. Only a small amount of power is lost as heat, the rest is converted to a useful output of a device, unless that device is a toaster, then I am wrong. See HERE.

Sorry, but they had it right, US voltage is nominally 120V RMS, roughly 172V peak to peak. Don't believe me, stick an ociliscope into your wall outlet.