Originally Posted by Maklaca
Can I add another question?
I have heard that sometimes sometimes amps actually put out more wattage than the amp's rating.
That being said, if I run a plexi 50W into a cabinet with two 25W greenbacks for a total of 50W rating, will that be OK, or would there be amp peaks that could blow the speakers?
Output specifications are usually given with equipment. A normal RMS wattage value is given at a specified distortion, usually a low percentage. Sometimes as a second specification a manufacturer gives a RMS wattage value at about 10% distortion, being maximum or maxed out for musical amplifiers. That wattage is usually between 1.5 and 1.8 times the normal wattage.
Now we have to keep in mind that RMS power is continuous. With musical amplifiers we are dealing with musical power, non-continuous.
Speakers too are rated RMS. Some manufacturers also specify a speakers musical power handling. That number is basically 2.0 times the RMS handling value.
Therefore a 100W amp may be able to put out up to 180W when maxed.
And a 100W RMS cabinet can handle 200W musical power.
Still for tolerances, safety and longevity it is best to go with speakers that are rated higher than your amplifers normal output.
Case in point; the old Bassman amps were capable of 40-50 watts with a 15 inch speaker that was rated about 40 watts or so. Bass frequencies are power hogs. Needless to say people were blowing the 15 inch speaker left and right. That is why the 4x10 came about.