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This is the deal with ratings. Smaller companies I don't have a clue how they come up with their ratings. All of the big boys use Klippel to verify parameters. They then use the CEA rating (Pat actually had a hand in setting those specs). Basically CEA ratings as power is considered is the power given the will cause a shift in parameters that will make the driver act differently from its original parameters. Basically is says the driver need x amount of power to act as intended. I do the same thing but take it a step forward and give the recommended enclosure for the power needed. It's a bit complicated as this will change in given alignments. The thing to remember that all this all about a rough round about figure NOTHING dealing with transducers are concrete as eveverything changes as the driver is played. We only try to get as close to real world as possible. The main thing as a consumer you want to look at is Large Signal Parameters. Most engineers do not understand this and it very easy to understand. Parameter of a sub played to Xmax and warm is Very different from that same driver played to 1mm. So would you want specs that showed the driver at 1mm (who only runs to 1mm Xmax) or do you want specs that show how the driver acts under normal operating conditions.

I was educated by a guy once...he explained to me how the input sensitivity gain works if the amplifier is rated at 100w rms you have to crank the gain to achieve this and if you turn the gain down to half your output is 50 w rms.......and so on..... and if a sub is rated 100w peak it will take that 100w rms I told the guy he was very knowledgable and he should do this shit professionally ......he thought I was serious....LOL

And this is why Q is da man. Puts stuff is term thae average guy can understand.

please stop lol. this is crazy. Sq refers to recreating music accurate to the source material. that's it. you're goals dont give a shit about SQ. You're looking for the loudest sub that doesn't sound like shit.

no reason to frankenstein a woofer to meet those goals with so many subs already on the market. vehicle acoustics and enclosure design should be the area of focus.

still have to run speaker wire

All the channels are being driven by the same head unit so not sure where the difference would be. The noise issue will never be removed. Every single head unit and amplifiers have given a certain degree of noise, but the key factor was being able to gain the noise out. Exactly what the gain is for. That doesn't account for the constant hissing sound regardless of gain position.

Personally, I think RMS ratings should only be the thermal rating of the coil, nothing more, nothing less. Any other rating should be called something else. I say this because it is the least meaningful specification given by a manufacturer, but none the less, it should be an objective one.

Really amped about this one ;-)

Original clamp.

mJust a noob trying to figure out all this adobe stuff. I did a good bit in school in gifted visual arts classes but that was over a decade a ago. I'll get the hang if it in a few weeks. These will be added to a full color catalog that will ship with product. The next page I'll be working on will be the recommended boxes with 3d model and cut sheet and expected frequency response. I'll also add in recommended port area for a variety of tunings. Basically everything needed to build the two boxes for each sub I listed plus a few tips to help with your own alignments.

what? why?

Phase Plug "Phase plugs may be placed in front of woofer cones, especially in horn-loaded loudspeaker designs. In the same fashion as compression driver phase plugs, the intent is to minimize higher-frequency wave interference near the driver. In this case, "high frequency" is relative to the intended bandpass; for example, a 12-inch (300 mm) cone woofer might be expected to reproduce 550 Hz energy near the top of its intended range, however, the wavelength of 550 Hz is approximately twice the diameter of the woofer, so wave energy at that frequency traveling laterally from one side to the other will be out of phase and will cancel. With a phase plug in the center, such lateral wave energy bounces off of the obstruction and is reflected outward toward the listener. Phase plugs for woofer cones are typically solid plugs positioned over the woofer's central dust cap, or in the center of the woofer, replacing the dust cap." - Sited from The Cook Book

Transfer Function As the Polk/MOMO subwoofers are optimized for acoustic suspension enclosures, we suggest you use this type of design. The acoustic suspension cabinet is a sealed airtight box, and is the easiest box to build. It also is a very predictable enclosure with easily calculated parameters, and it has a smooth natural sound. Properly built acoustic suspension cabinets have a flat frequency response that begins rolling off at 12 dB per octave at the frequencies below its cabinet resonance. This works very well inside a car because of a natural phenomenon called "room gain" that gives you roughly a 12 dB per octave increase in bass frequencies. You can roughly calculate at what frequency this gain begins by using the equation F= 565/L, F is the frequency at which bass gain begins, and L is the longest dimension of your "room." If, for example, you measured the longest dimension of your car as 5.65 ft., the room gain begins at 565/5.65 or 100 Hz. If your goal was perfectly flat frequency response you would design your cabinet for this particular car to have a resonance frequency of 100 Hz. Since most people want more bass than a flat frequency response yields, tuning the cabinet at a lower frequency, say 50 Hz, would give you a gain of 12 dB per octave between 100 and 50 Hz and flat response from 50 Hz down. The larger the cabinet, the lower the resonant frequency, and the lower the efficiency. Two identical systems will sound very different in a Honda vs. a Cadillac. The bigger the car the lower the frequency at which room gain begins.

For daily beating, I don't see the need. For competition, there is a purpose.

I am looking for a monster sub. either FI audio or Ascendant audio. I know they are in the same family but they make great subs. I am chasing a great sounding sub that can still achieve good numbers on the meter. My choices are the Mayhem or the SP4 What do you think about these subs based on my goals? Please only those that have experience with each.

I would say when you tune to 32Hz, It gives you the ability to play about 10Hz below tuning and sound well and also get good mid range bass from the woofers. That's why they recommend this tuning in their cut sheets. The Fs of the Q 12 D2 is 34, so I wouldn't tune much farther below 32.