I used to compete with Orion amps. The black amps are 2 channel amps that will easily handle impedances down to 1 Ohm no problem and truly double their RMS power with each drop in impedance.

The red Orion amps can run in 3 channel mixed-mono down to 2 Ohms (maybe less nowadays). If you have speakers that can handle that kind of power they really deserve an equal quality amp - underpowering them (400 watts for two 1200 watt speakers) can destroy them as well...

I guess my point is that there are amps out there that can handle that kind of load, unfortunately a lot of the mainstream amps aren't quite what they're cracked up to be...many were great at one time but the companies decided to go "mainstream" with their name which meant sacrificing quality...I cite JBL and Polk for example...

As for frying an amp, I've been there and will never forget the smell (my first Kenwood amp...)...that sucks dude ...I've also killed speakers by both underpowering and overpowering them, so my advice it to find an amp that matches (or comes close to) the rating of those speakers...

 

Max 1200W Sub doesn't mean it can handle 1200W continuously.
It probably means it can handle 1200W at peak bass.

You need to find out its continuous RMS (Root Mean Square) rating on that sub.

When you bridge your subs in parallel, total impedance the subs need is 2ohms. The amp has to be 2 ohm stable to connect to this sub setup, otherwise, things get hot and ugly.

Over powering the sub can definitely destroy it, but as for damaging the speakers when underpowering it, can you elaborate a bit?

Are you trying to say amp clipping thus damaging the sub?
Then it's not always true as long as you set the gain correctly and not go over its power handling limits.

 

No I'm talking about when you have too little amp for the speaker you want to power...even then gain won't help you because you can crank the gain on the amp, but when you turn up the volume you get to the point where the amp starts clipping - depending on the protection circuitry (if any) this will manifest itself as 'popping,' a 'muddy' or muffled sounding speaker, or plain 'distortion'...it just doesn't sound clear. Like when you take any stock system and just crank it - sounds like crap, vibrations, muddy sound, occasional popping speakers (i.e. sudden loss of power during excursion of the voice coils)...

It has to do with the dampening forces of the speaker - the obvious one is the speaker surround - some are paper, others kevlar, some foam, others rubber...the other is the strength of the magnet - more magnetic force means the voice coil is going to be harder to move (and will slow down quicker)...finally there's the resistance of the voice coil - an 8 Ohm speaker will sound more "crisp" than a 4 or 2 Ohm speaker with the same magnet because it has better dampening and will provide "cleaner" sound. It will take a bit more power to run though!

So if you overpower a speaker you can literally melt the voice coil...or you can frequently hit the excursion limit of the woofer thus wearing it out (which in my book is equal to destroying it!) a lot quicker -- especially since when it hits excursion limit it then begins to twist asymmetrically - creating weak points in the cone and surround that can affect sound quality at normal listening levels...and wear out the normal dampening qualityes of the speaker...

Underpowering a speaker can lead to damage via the same method...in older days when an amp hit its power limit and clipped the speaker would audibly 'pop' because it was playing at a loud volume and suddenly lost power (and inherent electric resistance) and would just snap back to its resting position but before it could get there the amp was sending signal again forcing the woofer out once more - very rough, jagged, not smooth transitions at louder volumes...do this enough and again you'll create fatigue points in the cone and surround over time which affects dampening and sound quality from that speaker.

Having said that, most newer amps come with protection circuitry that backs the power off quickly as the amp approaches clipping levels (helps keep the owner from having to replace speakers from sudden losses of power...i.e. underpowering with a small amp can hurt speakers)....Also most speakers are constructed of very resilient materials nowadays so they don't develop fatigue points as easily as older ones (but they still can)...but you still get muddy sound or buzzing/vibrations from the speaker when you start to max out your amp...this translates into a lot of erratic movement (not as dramatic as popping but not symmetric movement either which is the way it should be) of the woofer which can create weak points...my understanding from competing was that more speakers are destroyed (or damaged) from being underpowered than being mildly overpowered...

Anyway that's my thought on underpowering - essentially causes abrupt ASSYMETRIC transitions in the woofer where one part will be going out and another half will begin to pull back in thus torsing the cone/surround and over time literally 'creasing' the cone...I think of underpowering a speaker as a guy trying to bench press more than he's capable of...his arms (and the weight) are all over the place...if the woofer is the weight it's movements are severely constrained so when it gets asymmetric power to the voice coil or a sudden loss of power followed by a sudden burst of 'full power' (what happens if your amp doesn't have protection circuitry) then the woofer's only choice is to bend (no matter how stiff it is) or crash the voicecoil (where it actually hits the magnet) and over time this ruins sound quality...as will heat and direct sunlight...

If you think this is all crap that's fine, I'd appreciate a different opinion...maybe I can learn something too!

Sorry for the term paper...

 

If you were running two speakers bridged off of two channels, that is bridging and running parallel simultaneously, which each cuts the impedance in half. Your blown amp was running at 1 ohm (assuming 4 ohm speakers) when it roasted (I don't know of any amp which is not stable at 2 ohms). I've had friends of mine (against my recommendation) do the same thing to suck the most power possible out of the amp. It'll seem to work at first, but when you take a roadtrip and it cuts out... it may be too late.