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Did you know that the difference between 200W and 400W is only 3db 
Just sit closer and you will have better sound, I sit at about 7-10 feet away (2-3 meter)
Here is an interesting article from Musical Fidelity's web site:
Loudspeaker sensitivity and listening position
All loudspeakers’ sensitivities are quoted at XXdB at one metre for 2.83 volts. This sounds straightforward but, of course, nobody listens to their speaker at one meter (3.28 Ft). The average listening distance from a loudspeaker is around 3.5 (11.48ft) to 4 meters (13.12ft). This is where the fun starts.
Sound pressure level from a loudspeaker reduces by 6dB for each doubling of distance. This is highly significant. If a loudspeaker were rated at 87dB sensitivity (in other words, you get 87dB of level for 2.83 volts input) at one metre, then at four metres, you have 12dB less level. This is huge amount of sound pressure level difference.
Again, many people don’t understand the significance of ‘just a few dB’ in power terms.
Amplifier power and dB Watts
The vast majority of people have no idea of the practical connection between watts and dB watts. Let us enlighten you. Watts are simply a measure of an amplifier’s heating power. There is no intuitive relationship at all to listening level measured in dB. Ignorance about the practical connection between watts and dB watts is one of the biggest causes of the problems of the business.
When we explain the basic relationship between watts and dB watts, you might begin to understand why amplifier manufacturers are anxious to sweep it under the carpet. Essentially, each dB step in sound pressure level requires a 25% increase (approx) in power. A 3dB increase requires double the power. This sounds incredible, but it is true. Perhaps now you might glimpse why amplifier manufacturers are anxious that you don’t look at amplifier power in terms of what the amplifier actually does with music. Below is a chart which converts watts to dB watts. "I think this is at 8Ω?"
30W 15dBW
40W 16dBW
50W 17dBW
63W 18dBW
80W 19dBW
100W 20dBW
125W 21dBW
158W 22dBW
200W 23dBW
251W 24dBW
316W 25dBW
400W 26dBW
500W 27dBW
631W 28dBW
795W 29dBW
1000W 30dBW
How to put together a dynamically accurate system
Once you have converted amplifier power to dB watts, it is pretty straightforward to work out how much power/loudspeaker sensitivity you need to achieve a given peak level.
Slide Rule
The OK/green area starts at 106dB, which is quite a lot less than you would expect to hear in a concert hall.
A top quality hi-fi system should be able to deliver a 110dB peak. An adequate hi-fi system should be able to deliver half that level, a 107dB peak. And to be helpful, I suppose a system that delivers 1dB less than that could still be called hi-fi. That’s how we got to the green section starting at 106dB.
But my 50W-100W amplifier seems to sound okay
One of the most confusing aspects of all this power/loudspeaker sensitivity stuff is that it doesn’t seem to offer an explanation of how lower-powered amplifiers seem to offer a ‘room-filling sound’. The apparent paradox arises because of a phenomenon called reverberant field. This is the sonic field created between the loudspeakers, and it is made up of the sound produced by the hi-fi system plus echoes and other resonances caused by room irregularities, which linger for a few micro-seconds. Paradoxically, the more distortion an amplifier produces, the richer that reverberant field sounds. When the reverberant field is enriched with distortions and non-linearities, which then reverberate, this creates the illusion of fuller, richer sound. Even more paradoxically, a higher-powered amplifier, which is not limiting or clipping, will sound quieter then the inferior amplifier which is distorting regularly.
However, it is beyond dispute that the smaller amplifier will be incapable of ever, under any circumstances, producing a significant dynamic attack. In our opinion, dynamic attack is vital to the realistic reproduction of music.
Just sit closer and you will have better sound, I sit at about 7-10 feet away (2-3 meter)
Here is an interesting article from Musical Fidelity's web site:
Loudspeaker sensitivity and listening position
All loudspeakers’ sensitivities are quoted at XXdB at one metre for 2.83 volts. This sounds straightforward but, of course, nobody listens to their speaker at one meter (3.28 Ft). The average listening distance from a loudspeaker is around 3.5 (11.48ft) to 4 meters (13.12ft). This is where the fun starts.
Sound pressure level from a loudspeaker reduces by 6dB for each doubling of distance. This is highly significant. If a loudspeaker were rated at 87dB sensitivity (in other words, you get 87dB of level for 2.83 volts input) at one metre, then at four metres, you have 12dB less level. This is huge amount of sound pressure level difference.
Again, many people don’t understand the significance of ‘just a few dB’ in power terms.
Amplifier power and dB Watts
The vast majority of people have no idea of the practical connection between watts and dB watts. Let us enlighten you. Watts are simply a measure of an amplifier’s heating power. There is no intuitive relationship at all to listening level measured in dB. Ignorance about the practical connection between watts and dB watts is one of the biggest causes of the problems of the business.
When we explain the basic relationship between watts and dB watts, you might begin to understand why amplifier manufacturers are anxious to sweep it under the carpet. Essentially, each dB step in sound pressure level requires a 25% increase (approx) in power. A 3dB increase requires double the power. This sounds incredible, but it is true. Perhaps now you might glimpse why amplifier manufacturers are anxious that you don’t look at amplifier power in terms of what the amplifier actually does with music. Below is a chart which converts watts to dB watts. "I think this is at 8Ω?"
30W 15dBW
40W 16dBW
50W 17dBW
63W 18dBW
80W 19dBW
100W 20dBW
125W 21dBW
158W 22dBW
200W 23dBW
251W 24dBW
316W 25dBW
400W 26dBW
500W 27dBW
631W 28dBW
795W 29dBW
1000W 30dBW
How to put together a dynamically accurate system
Once you have converted amplifier power to dB watts, it is pretty straightforward to work out how much power/loudspeaker sensitivity you need to achieve a given peak level.
- Convert amplifier power in watts to dB watts.
- Add the amplifier power in dB watts to the loudspeaker sensitivity in dB.
- Deduct the listening position attenuation (between 7dB -12dB).
- You now have your system’s peak level ability at your listening position.
Slide Rule
The OK/green area starts at 106dB, which is quite a lot less than you would expect to hear in a concert hall.
A top quality hi-fi system should be able to deliver a 110dB peak. An adequate hi-fi system should be able to deliver half that level, a 107dB peak. And to be helpful, I suppose a system that delivers 1dB less than that could still be called hi-fi. That’s how we got to the green section starting at 106dB.
But my 50W-100W amplifier seems to sound okay
One of the most confusing aspects of all this power/loudspeaker sensitivity stuff is that it doesn’t seem to offer an explanation of how lower-powered amplifiers seem to offer a ‘room-filling sound’. The apparent paradox arises because of a phenomenon called reverberant field. This is the sonic field created between the loudspeakers, and it is made up of the sound produced by the hi-fi system plus echoes and other resonances caused by room irregularities, which linger for a few micro-seconds. Paradoxically, the more distortion an amplifier produces, the richer that reverberant field sounds. When the reverberant field is enriched with distortions and non-linearities, which then reverberate, this creates the illusion of fuller, richer sound. Even more paradoxically, a higher-powered amplifier, which is not limiting or clipping, will sound quieter then the inferior amplifier which is distorting regularly.
However, it is beyond dispute that the smaller amplifier will be incapable of ever, under any circumstances, producing a significant dynamic attack. In our opinion, dynamic attack is vital to the realistic reproduction of music.
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