nevyznam sa ale toto som vygooglil

RMS This relates to the power output an amplifier will produce without any distortion. Effectively, it is the usable power on tap, and is used to compare the power ratings of amps from different manufacturers.

PMPO Stands for peak music power, used on gear that needs to look more powerful than it is. If you see a ghetto-blaster advertising 160watts output, ignore it

prepocet neesxistuje ale u pc zostav je to asi RMS *10-30=PMPO

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RMS --------- RMS power the driver can safely handle.
Peak Power -- The amount of power the driver can handle for 20% of the time.
System Power - The amount of power required to burn the voice coil.
Excursion Limit Power -- The power required to move the voice coil to its mechanical limit.
P.M.P.O. -- Peak Music Power Output. The most meaningless power rating of all. It is for marketing only, and indicates the amount of power the amplifier will put out in a very short amount of time such as on music peaks.

The published power ratings and how they are determined vary among manufacturers. One thing is for sure, though, they are usually higher than any of the technical design ratings. For instance, some speaker manufacturers rate their speakers at twice the RMS value, while others use up to four or five times the RMS value for their rating. They make the assumption that no one would put a steady tone (RMS or continuous power) into the speaker for very long, and also realize that music is transient in nature. Another big problem with truth in power rating is the fact that copper has a positive temperature coefficient. The voice coil wire is copper, so as soon as it starts heating up its resistance goes up. All electromagnetic devices are current devices, that is to say, they respond to the current through them, not the voltage across them. For many reasons, speakers have always been driven by amplifiers that have voltage source outputs rather than current source outputs. This means that for a given input, the amp will put out a certain voltage and the assumption is made that the load (the speaker) resistance won't change much. In reality, as the amp puts out enough voltage to put, say 40 watts into the speaker, the speaker voice coil begins to heat up, its resistance goes up, and before you know it, the speaker is only drawing 20 watts from the amp. Speaker manufacturers are well aware of this fact, and make use of it in determining their published power ratings. Of course, if you had an amp whose output was a true current source, it would keep pumping 40 watts, regardless of the resistance change in the voice coil.The common term used to describe this effect is Power Compression. An example of this is after you've gigged for a lengthy period of time and you notice the speakers in your amp seem to lose attack, the loudness drops, and they get kinda mushy, you are experiencing the effect of power compression.
Some manufacturers rate their speakers based on a mechanical limit rather than an electrical one. WeberVST for instance, rates its model P10Q at 20 watts, because at around 30 to 35 watts the voice coil will bottom out and cause a cracking sound. The voice coil itself would handle much more than 20 watts of electrical power, however.