Speaker question. RMS?

Question

what is rms?

what does it stand for, if it stands for anything.

how does rms convert to watts?

Answer 1

rms is just the rated max power that you can safely use the speaker at.(for extended periods)

Answer 2

RMS mean Root Mean Square, which is mathematical formula for acquiring an average value for Alternating Current waveform (AC).  If your speakers are rated at 100 Watts RMS, that means that they can handle 100 Watts of continuous "clean" (non-distorted) amplifier power and can momentarily handle peaks of about 200 Watts.  Abbreviations for speakers also use SPL (Sound Pressure Level) rated in dB (Decibels), which tells you how efficient a speaker is.  The higher the dB rating the less amplifier power is needed to produce the sound.

Answer 3

"also are there any other add on abbreviation's like Mrms. is"

"Peak" or "Peak Envelope Power" or "PEP"

Sound is a wave. If you measure power at the top of the wave - you get bigger numbers so sleazy companies sometimes print power numbers in large fonts, then in tiny font mention that it is peak power. Honest companies use RMS.

OHMS

Speakers have a nominal resistance of either 8, 6 or 4 ohms.

The close the number gets to zero, the closer the speaker appears to be a short-circuit/draws more current/generates more heat/damages equipment.

BUT - power ratings for the same receiver can be:

- 70 watts into a 8 ohm speaker

- 105 watts into a 6 ohm speaker

- 140 watts into a 4 ohm speaker

Sleazy companies often measure power with a 4 ohm speaker to make the units appear more powerful than they really are.

So these look more powerful than say a Yamaha, Denon, Pioneer receiver that publish power into 8 ohm speakers.

NUMBER OF SPEAKERS

Sleazy companies print power numbers, but in the fine print mention that it is using "stereo" mode: only 2 speakers are attached.

Honest companies report power with 5 speakers attached or publish separate stereo and 5-speaker power numbers.

My advice: dont just look at power numbers as there a 5 different ways to measure power and make something appear better than it really is.

Answer 4

RMS is a form of average.  It means "root mean square" and is used for AC currents like those used to drive speakers.  It provides a true representation of the power available from the voltage or current represented.  However it is not a unit in itself, and must be used with actual units like volts rms or watts rms which means "average" volts or "average" watts.