So I liked my 40C enough that I went shopping and caught a gently used 800HD. But I got no cabs. I'm looking at the rumble cabs but the power handling spec seems to be just short of taking the 800. IE, we're putting out 400 watts @ 8 ohms but that 210 cab says 350 watts. The 115 is only 300.
Are those specs "close enough" or is it courting disaster if I really cranked it up? Or am I supposed to be getting a non-rumble cab to go with this 800HD?
Welp, right or wrong, I walked into Dietze this afternoon and there was a Rumble 115 sitting in their showroom so now it's in my trunk. Guess I'll just have to watch for signs of distortion/abuse. As the gent above said, I don't have to turn it up to 11. And in my basement it will probably never turn up too far.
The 800 is way too much amp for me, but more is always better. I guess.
... ... So I'm the consummate beginner. I probably didn't need to step up to a 800 watt amp ..., but screw it, I wanted it and nobody in the corn field is going to complain about my loud bad technique.
Good for you, Nebby! Go for the gusto! Just remember that a wise person once said, "With great power, comes great responsibility." Often, that responsibility is to protect others from harm.
The Rumble 800 HD is, indeed, great power. And, though there is good reason to believe that the Rumble 210 cab can handle that power, alas, the same cannot be said for the 115. The driver in the 115 cab is the same as in the Rumble 200 combo, where it can only ever see up to 140 watts. Therefore, although Fender is known for their conservative ratings, it would be unwise to push a single 115 alone very hard with the 800 HD.
So, how much is too hard, you ask? Well, you are correct to put your ears on guard. But, to give them
some rest, you should consider using only a very conservative Master control setting. Unfortunately, I know of no reliable guide for that setting. But, I've read many who claim that, on many/most amps, just halfway up,
at 12 o'clock,
can be 80% to 90% of full power (320W to 360W in this case)!
If that's true in this case, then a Master setting of
just 10 o'clock, or maybe 10:30, surely no more than 11 o'clock, depending on other EQ settings used, could put you at or very near the maximum rating of the 115.
The exact same is true for using
two Rumble 115 cabs, since each one could see up to 400W. But
three Rumble 115 cabs would divide the full 800W into a very safe 267W for each cab! You could then shuck that whole cornfield with that!

I hope this helps.
.