how much over RMS IS TOO MUCH

[dreadknot55]

a serious question my fronts are BIC Amercia Acoustech Platinum Series PL-89 tower speaker with 250 rms an a peak of 600watts at 8ohms

im currently driving by a crown xli 800 at 200watts at 8ohms per ch with the signal knobs at 70% an -7db per ch from my outlaw audio 976 balanced receiver connected via xlr

with the amp input Sensitivity set at 1.4

now some stuff sounds great some not no after a lot of adjusting an tuning of gains an eqs an etc i belive what i need is more power iv concidered using my xls 1502 to power my fronts with its 8ohm output at 300watts rms my qusetion is (is that safe 50watts over the pl-89s 250 rms in)

[StainlessSteve]

I just want to say something that's been bugging me. RMS means Root Mean Square, and it applies to AC Voltage or AC Current, in converting them to their equivalent in DC, because they alternate and DC doesn't. But watts are watts, AC or DC, so there is no such thing as "RMS watts". https://en.wikipedia.org/wiki/Root_mean_square
Rant over.

I would suggest simply do not turn up your speakers to the point where you hear distortion. Listen for port chuffing, woofer breakup, etc. If you smell your coils getting hot (which you will if you put your nose up to the port while playing at too high volume) turn it down. But for the most part, finding an exact limit is pretty much impossible without burning or bottoming out your speakers. 

There's a good chance that automatic EQ adjustments considerably lessened the maximum output power of your amps by reducing the input signal. This is very common with auto-EQ methods, but you can always turn it off, see if it gets considerably louder without touching the amp gain knob, then turn it back on and see if it gets quieter again. If so, then you found your problem. Don't get a bigger amp if you could already push these speakers to destruction with that amp (which I'm sure you could). Instead, just manually EQ using REW or other software. Or if you have the money, pay someone to do it for you.

Good luck,
-Steve

[Ricci]

It's  complicated to answer. It really never is as simple as labeling something 500 watts. Audio signals vary constantly. The speaker impedance and diaphragm excursion vary with frequency. Voltage and current vary into the impedance of the speaker. The key consideration is usually duration of the signal as far as burning coils goes. The other is the peak signal possibly causing mechanical damage to a driver. Most speakers will handle extremely high power inputs at certain frequencies if the duration is very short. At other worst case frequencies they may be cooked with far less power than the rating if the duration is long enough. 

The answer is it depends.