Anonymous asked in Consumer ElectronicsHome Theatre · 9 years ago

speaker question - what 300 watts total power output and 40 watts RMS total means.?

looking to buying Akai 5.1 DVD Home theatre system (ADVD51)

seen at :

im wondering what 300 watts total power output and 40 watts RMS total means.

for example does this mean that it can put out 300 watts but the speakers only put out 40 watts ?

also, any ideas how loud do you think itll be for a room approx 4x4 meters ?

thanks .

5 Answers

  • Lance
    Lv 7
    9 years ago
    Favorite Answer

    The 300 watt total power is really a meaning less figure its used to represent peak power but peak power can be measured in different ways for instance it could be a burst signal at 1hz for a millisecond of time creating 300 watts at 10 percent distortion or even 15% or 20% over that time period.. who knows....this type of test is going to be meaningless in real world conditions because you will never feed a signal like that into your use to be that peak power represented 2X RMS...but you can see this is no longer the case... RMS is a little more standardized its usually a sustained signal of at least a few seconds but again the measurement could be only at 1hz and could be at 10% distortion...the most meaning full measurement is going to be 20 to 20K measurement at .09% distortion or less, because this is what you really can hear...this is why it is so ridiculous when people ask... can I use my speakers that are rated at 150 watts with my amp that is only 75 watts because basically its like trying to compare apples to oranges with blind folds on and your hands tied behind your back....

    • Login to reply the answers
  • 4 years ago

    For the best answers, search on this site

    If your amp is rated at 600 watts RMS, it means that your amplifier has the potential to create 600 watts continuously, in a given frequency range. But, there are a lot of variables involved. It depends on the wiring. The length and diameter of the power and ground cables, supplying the amplifier with power, can limit it's output. If, it is too small. Also, it is dependent on the wiring of the speakers. Depending on the ohm load presented to the amplifier, it will vary the amount of power that it can create. Example: If your amp is rated at 600 RMS at 2 ohms, you may only get 300 - 400 watts RMS at 40 ohms. The only rule of thumb used to be, you get double the power every time you cut the resistance in half. In real world conditions, this isn't the case. Because of the efficiency issues involved, you may only see a 50- 75% increase in power.

    • Login to reply the answers
  • Anonymous
    9 years ago

    These specifications are using the terminology incorrectly. They even spelled "Bass" wrong. The term "output power" should not be used with speakers. Speakers do not put out power unless they are active speakers. That term is reserved for amplifiers. When referring to speakers, wattage ratings are how much power they will take before damage occurs. When referring to amplifiers wattage ratings are how much power they will deliver at a specific impedance and distortion rating. The lower rating is the continuous amount and the higher one is a "peak" or momentary amount, usually the amount of power they will deliver just before going up in a puff of smoke. "Total" refers to the amount for all channels combined. 40 watts is pretty small for a combined rating. You do the math. The 300 watt rating will tell you how much nasty, distorted, transistor burning power it will push out in it's final milliseconds. However I'm sure it will be able to fill a 12'x12' room with moderately loud sound. Will it be like being in a club with a live band where you have to scream to talk to your friend? No. Will it be enough to make your mom pound on your bedroom door and scream at you to turn it down? Most likely yes. But what do you want for under $100?

    • Login to reply the answers
  • Susan
    Lv 4
    4 years ago

    This is not total wattage. What RMS is is the continuous power being sent. That's why when purchasing audio, amplifiers, stuff like this, we go off of continuous power because it's what it will always be taking. It will rarely ever hit it's total or maxx wattage.

    • Login to reply the answers
  • How do you think about the answers? You can sign in to vote the answer.
  • 9 years ago

    40watts is how loud,they are, honestly they should be ok for your size of room.

    • Login to reply the answers
Still have questions? Get your answers by asking now.