what's watt?
Scooby Regular
Joined: Sep 2006
Posts: 7,576
Likes: 0
From: Worthing..
Root Mean Square.
Effectively its the average amount of power and Amp can continually produce.
The total output is usually the total out of the amp - So if it has 2 channels and outputs 5w per channel then the total output power will be 10W
Effectively its the average amount of power and Amp can continually produce.
The total output is usually the total out of the amp - So if it has 2 channels and outputs 5w per channel then the total output power will be 10W
Thread Starter
Scooby Regular
Joined: Nov 2001
Posts: 4,093
Likes: 0
From: sheffield
still confusing, what is important , or makes it better?
Scooby Regular
Joined: Sep 2006
Posts: 7,576
Likes: 0
From: Worthing..
Well it;s only important in terms of what is accetpbale to you.
The higher the number - in both instances - the louder the amp will go. If you have an amp with an RMS of 2W and a total output of 4W, then it isn't going to be very loud.
As an example an average car Stereo often lists output per channel - So it will be Max power out put 50W X4 and RMS of 20WX4 (4 channel outputs).
Obviously only you can decide what is loud enough for you in the situation you are using it in.
Have a look at the steroe in your house, see what the RMS/Total output is for that, and make your decisions base don that.
The higher the number - in both instances - the louder the amp will go. If you have an amp with an RMS of 2W and a total output of 4W, then it isn't going to be very loud.
As an example an average car Stereo often lists output per channel - So it will be Max power out put 50W X4 and RMS of 20WX4 (4 channel outputs).
Obviously only you can decide what is loud enough for you in the situation you are using it in.
Have a look at the steroe in your house, see what the RMS/Total output is for that, and make your decisions base don that.
Scooby Regular
Joined: Jul 2006
Posts: 912
Likes: 0
From: Swindon, Wilts
The output power of every amplifier or hifi can be measured in various ways - RMS or "total power" or "peak power", etc. it's a bit like measuring temperature in degrees F or C or K...
However, if you're comparing products then the important thing is to be sure that you compare like with like. So always compare RMS figures, for example.
Trying to compare an RMS figure with a "peak power" figure is like saying that 20C is 'worse than" 45F - it doesn't work.
As "peak power" and "total power" can mean various things to various people - but is often the absolute flat out, distorting like hell, volume on 10, power that the amplifier can kick out (either both channels together - as in total power - or normally 'peak power' per channel) - it really is better to compare RMS figures.
Does that help?
However, if you're comparing products then the important thing is to be sure that you compare like with like. So always compare RMS figures, for example.
Trying to compare an RMS figure with a "peak power" figure is like saying that 20C is 'worse than" 45F - it doesn't work.
As "peak power" and "total power" can mean various things to various people - but is often the absolute flat out, distorting like hell, volume on 10, power that the amplifier can kick out (either both channels together - as in total power - or normally 'peak power' per channel) - it really is better to compare RMS figures.
Does that help?
You will find a lot of products sold on numbers, just the same as computers. The maker will put on big stickers shouting out just how much "power" the thing has so that you buy it.
Its poor marketing practice, and does not really give you the information you need to know. If you are into computers the analogy would be the ones where they shout out that you are getting a 128Mb graphics. Only to find that its shared system ram, dog slow and unable to produce donkey kong in a playable frame rate.
The same happens with Hi-Fi. They quote silly large numbers hoping that you think the system with the bigger number is better. RMS is the industry standard for quoting power. If you cannot find out what the RMS is of your system expect it to be of poor quality.
There are also different ways of stating power. For example some dubious systems quote power at frequencies that are inaudible, or cannot sustain, or a temperatures your room will never be at. Or when they are distorting so badly you would want to run a mile.
Lastly, just to confuse matters even more, is that there is little correlation between power and volume. A powerful system may not sound louder than a system with less power. This is because different speakers have different levels of resistance. Some speakers need more power to produce a certain volume. Quote often the better the speaker, and the larger the speaker the more power it will need.
This is why you can have high powered quality amps and speakers that do not reach volumes that are higher than much lower powered stereos you get from Dixons. The power of the better system has gone into driving better components giving you better quality sound.
The short answer is to make sure you listen to what you are thinking of buying carefully, and preferably in an environment close to how you will have it. No point listening to a small hifi in a small room if you are going to put it in a hall. It may sound like it has the power to fill the space on demo, but will not likely fit the bill when you get it home.
Its poor marketing practice, and does not really give you the information you need to know. If you are into computers the analogy would be the ones where they shout out that you are getting a 128Mb graphics. Only to find that its shared system ram, dog slow and unable to produce donkey kong in a playable frame rate.
The same happens with Hi-Fi. They quote silly large numbers hoping that you think the system with the bigger number is better. RMS is the industry standard for quoting power. If you cannot find out what the RMS is of your system expect it to be of poor quality.
There are also different ways of stating power. For example some dubious systems quote power at frequencies that are inaudible, or cannot sustain, or a temperatures your room will never be at. Or when they are distorting so badly you would want to run a mile.
Lastly, just to confuse matters even more, is that there is little correlation between power and volume. A powerful system may not sound louder than a system with less power. This is because different speakers have different levels of resistance. Some speakers need more power to produce a certain volume. Quote often the better the speaker, and the larger the speaker the more power it will need.
This is why you can have high powered quality amps and speakers that do not reach volumes that are higher than much lower powered stereos you get from Dixons. The power of the better system has gone into driving better components giving you better quality sound.
The short answer is to make sure you listen to what you are thinking of buying carefully, and preferably in an environment close to how you will have it. No point listening to a small hifi in a small room if you are going to put it in a hall. It may sound like it has the power to fill the space on demo, but will not likely fit the bill when you get it home.
Last edited by Luminous; Feb 13, 2008 at 01:05 PM.
Trending Topics
Scooby Regular
Joined: Oct 2001
Posts: 2,223
Likes: 0
From: X5 and MCS JCW country....London :)
Peak power also has a % distortion applied to the value and different companies apply different %'s. Therefore two identical peak powers are not even alike. In addition they can also quote power on 2 Ohms / 4 ohms / 8 ohms resistance etc that will effect the RMS and the peak power. Always compare ohms and RMS for a true understanding.
Thread
Thread Starter
Forum
Replies
Last Post