Depends on the size and quality of the speaker. Also depends what you are using the speaker for. If you are using a microphone to make a speech or commentary, then it is more than enough power to do the job. But if you are using it for music for maybe a party or something along the lines, maybe you might need more power. But even that could be enough if you know what you are doing. If it is a car stereo using a car speaker in an external box that you can detach from the car, then yes it is should be good enough using it for mids and trebs. Not good for a sub, however, you will need more power to have nice, hard bass. Make sure that the Ohms of the bass matches the Ohms of the amplifier being used. You also need to know that RMS is the total amount of continued current that is being pushed to the speaker. Has nothing to do with the total amount of watts that the amp uses and has. Whether the amp says 100 total watts or 1000 total watts, that is only the amp and not RMS. RMS is the total amount of current supplied to the speaker in a continous form, while Total Watts are the total watts that the amp has.