Sopra 2 Bass

This world is insane!

You have no idea

Great advice from Eric and James633.

Are you achieving satisfactory results when you use your tone controls? If you are I would stop and enjoy your system. You should not care what others think, it is your system for your enjoyment, not anyone else.

In tracks where I expect a punch.

Low end impact is a tall order for a couple of 7” woofers.

Should I consider a sub?

Maybe. What kind of music do you listen to. If you like rock or electronic and maybe even modern day country, a sub can be of substantial benefit. If you listen to other genres than maybe not so much.

Beware; while properly integrating subs into a system can bring great joy and satisfaction, improperly integrating a sub can bring great headaches and frustration.

Keep in mind that if you are pressurizing your room to 80 db SPL at 1K Hz you will need to pressurize the room to approximately 115 db SPL at 40 Hz in order to have 40 Hz sound equally as loud as 1K Hz (per ISO standard 226:2003, equal loudness curve)  Also keep in mind that with most rock music it is desired to have 40 and 50 Hz sound louder than 1K Hz.

Lastly, it is not always a lack of bass that is the problem but an overabundance of mid range. You probably are getting some room gain in your mid range frequency band. On your MA9000 you might try and bump up the 50 Hz, dial the 100 Hz back a tad and the 1K and 2.5K Hz controls back a bit more, or a lot if need be, and see how that sounds to you. 

Halfway through the track there was a quick pop from the right speaker.

Once again I agree with James633, this most likely was an over excursion of the woofer due to boosting the low end and the over all volume you were using while playing the track.  Been there and done that,  but I don’t recommend doing it on a regular basis. As long as you are not hearing any distortion form the speaker you did not do any real damage, but you did reach the limits of your system with those particular settings.

If what you were playing was at your desired level of volume and low end thump when you heard the pop, you should probably seriously consider adding subs in the future. I wouldn’t add just any subs either, you will want subs that have plenty of power and least a 12” driver if not larger.

Leaves me wondering what a clip sounds like vs something else...

Im my experience when an amp clips you would hear that same pop of the driver hitting its excursion limits followed immediately by heavy distortion and lack of volume due to a blown driver. The amp it self would suffer no damage.

Since I wasn't at your party and was unable to experience the volume level you were reproducing, it is impossible for me to know for sure, and I certainly do not want to contradict your dealer, but I've been in your shoes more times than I care to count, and I still think that there was a low end dynamic spike in that track and with you having the 25 Hz control and possibly the 50 Hz control adjusted were you do, that was just a little more low end power than that 7" driver wanted to see. Had it been the amp reaching its limit I think that driver would have been toasted, but again that is just my opinion.

I'm also wondering it I should have been a bit more patient and waited for the MA-12000.

Not sure why you think the MA12000 would work better. If you had run out of power with the MA9000 the fifty extra watts probably would not have bought you anything. You would more than likely need an amp that could deliver 600 watts or more if you are clipping a 300 watt amp.

In short, I'm in it deep.

I hear what you are saying (typing?) It's very easy to get sucked in. The best thing to do is just take a breath and relax. It sounds like you are enjoying what you have so no real need to rush. Figure out what you want to improve (sounds like you have) and proceed slowly. Do your homework. In my opinion, though it's not being asked for (too bad I'm giving it anyway) is that the improvement in DAC's in the next few years will be greater than the improvement is subs so unless you are extremely unhappy with what you have now, you might be better off upgrading that later.

My second eyebrow has now joined my first, far north of my eyeballs hearing you have four subs. How did you know you needed more than two?

A lot of guys are going the four sub route including myself. I started with one, then two and now four. Not to get more bass, but to get better bass. Multiple subs are more of an electronic version of low frequency room treatment. They greatly help in smoothing out the low end frequency response of a room. There are a great many threads on audiogon that discuss the merits of multiple subs, aka DBA, distributed bass array. Also see AudioKinesis "Swarm"

How were you able to dial-in all four?

Personally, I found it much easier to dial in four than one, because four reduced or eliminated many of the problems usually associated with subs, but I did recently fine tune my set-up with the help of REW.

Next time, if there's a next time, I push past 60% I will have the tone control disabled and will be watching the power guard lights with my finger on the mute or volume control.

Not knowing what track you were playing when the incident happened I strongly suspect it was the 25 Hz control that caused the problem. You might try setting the 25 control at neutral or lower, increasing the 50 to 3/4 and reducing the 100 to 1/4 and see if that sounds OK to you, though you still might not get much more volume. In my opinion a 7" driver is just too small to reproduce loud bass much below 60 Hz.