MTX 311D to NOS8 Bazooka Tube

I recently decided it was time for an upgrade from my POS receiver.  While contemplating alturntive decks, I decided I would add a bazooka tube and amp also.  I am partial to bazooka tubes because I have heard one in my buddies car, and was impressed(it is enough for me). I own a 2001 Silverado Reg cab so I am limited on space.  I've set my affections on a RX- Series NOS8 Bazooka Tube which I intend to stick behind the passengers seat, or rip out the middle console put it there and build around it. 

I am realitvly new to the car audio scene but am zealous as ever about it.  This new found zeal inspired me to learn what I could about decks, amps, watts, , rms.. ect ect...  however one thing that I am still unsure about is the the 12.5v, and the 14.4v ratings.  I did read a previous post about the 2 and I did gather some understanding from it.  Now to the point:

I just baught (which is the first piece to my set) a MTX 311D amp. I plan on running the NOS8 Bazooka Tube, and my deck is going to be CQ-DFX983U.  The 311D's Specs Look like this: 

RMS at 12.5v = 100 Watts x1 into a 4ohm load

Dynamic Power at 14.4v = 155 Watts x1into a 4 ohm load

I baught this amp looking at the 14.4v hoping that 14.4 was the standard because the bass tube I plan on getting has a recommendation of 150 wats RMS and it is a 4ohm bass tube. http://bazooka.com/productAutoPassiveBTsRX.asp?id=157

So now that I have the amp in my hands, I just was curious as to if I need a bigger amp.  I know now that I should have went by the 12.5v rms value, but I didnt, and now im wondering if there is anyway to supply a constant 14.4v to my amp.  Would a cap benifit me at all, and my alternator is 108 amps(if that means anything) and my battery is less than a year old (maybe 6 months).  Any suggestions ?

Well, you may still be underpowering the subwoofer somewhat.  Your amp's rating of 155 Watts "dynamic power" at 14.4V is another way of saying "peak power".  For true RMS power, you'll probably get the advertised 100 watts at 12.5v, and perhaps slightly more power with 14.4v, depending on how tightly regulated the amp's power supply is.

At 100 Watts, you're running about 30% below the recommended 150W, but even with a 150W amp, you wouldn't be playing it that loud all the time anyway, so it's not like 100W is going to hurt it or anything.  You just might be disappointed in the output you get with this setup.  The Bazooka tube is basically an 8" sub in a ported enclosure.  That setup with 100 Watts behind it isn't going to shake the world, but it should be enough to provide a nice bottom-end to your music.  Since it is a ported enclosure, be sure to play around with different places to put the sub.  I think Bazooka recommends facing the port into one of the rear corners of your trunk, so that would be a good place to start.

Scott Gardner

Capacitors are one of my favourite subjects, because there's so much bad information out there.  Capacitors store energy, and are useful to help provide additional current during loud musical transients. 

Without a capacitor, if your car's accessories and stereo ask for more current than your alternator can supply, it will have to dip into the battery for the extra current.  Batteries have a relatively high internal resistance, so the current draw causes a voltage drop.  This is the same reason why a healthy battery will drop from 12 volts to as low as 9.6 volts while cranking the engine over.

Capacitors have a much lower internal resistance than batteries, so they can provide an occasional short burst when needed, with almost no voltage drop.  Keep in mind that it won't make your bass louder or "tighter" or anything like that.  They're useful for keeping your lights from dimming when the bass "hits".  Also, if your alternator can't keep up with the *average* current demands, no capacitor in the world is going to help, because the alternator will always be overloaded, and it will put a constant drain on the battery.  This means that the capacitor will never be able to recharge fully, and your battery will eventually go flat.

So, capacitors are useful in those cases where your alternator output is low enough that you're getting dimming/flickering lights, but high enough that your battery's not going dead after driving around all day.

Scott Gardner

Wow, that's good stuff, so after I get this all set up, I'll see how my voltage goes. And if my truck cant keep up i'll try a capacitor. Does it make sense to have more than one capacitor? Is it possible?

 I do plan to get new 6½'s for my doors and 4x6's for the rear pillars in my truck, and power them with an amp (but that wont be untill the budget permitts)  Do you all have any suggestions as to a good amp and speakers?  2 channle or 4 channle?

Thats great advie also, thanks, how exactly do you ground the amp to the battery? Any websites show you how?