Impious

It's going to be hard for us to tell you which set of features are important to you. Preamp output voltage isn't important, so scratch that off your list. If you primarily use your Ipod, keep the Alpine. If you use both Ipod and CD, keep the Kenwood.

If your main goal is vibration damping in various areas in your vehicle, I think I would still stick with the Dynamat Extreme. It gives you the most square foot coverage for the money out of the listed options and is a high quality damper, so you're not really sacrificing anything.

I wouldn't believe the specs on that website. Looking @ US Amps website, they rate the amplifier at 75w x 4 @ 4ohm and 90w x 4 @ 2ohm (2ohm rating is the same on the audiosavings website), which would correlate to only 180w x 2 @ 4ohm bridged.....not 500w. US Amps website states 500w x 1 @ 1ohm bridged, but I would presume they were meaning the sub channel is 500w @ 1ohm and not that the main channels were 500w RMS when bridged. The Memphis 16-MC5.1400 has more power capabilities, assuming I'm correct, if that's what you're looking for.

The other option is ofcourse to sell the gift cards and use the cash to buy whatever you want from where ever you want.

Out of those options, I personally would choose the Dynamat Extreme. It's far from an affordable deadener, but it is one of the better deadeners on the market. Never heard of Q-Mat and their site didn't have any actual info on the product I could find quickly. Rblox I believe is a lower end product. I would go with a mat before a liquid deadener for the primary deadening layer. And going from memory, I believe the Dynamat Extreme is a better product than Roadkill, but Rudy on here would be the one to give expert advice regarding sound deadening.

Crest Factor Before we can discuss amplifier headroom, we first need to discuss the music we are listening to. And the concept we need to understand is that of crest factor. Sine waves are the simplest tone. Sine waves are the "test tones" that many people use in this hobby for various reasons, although most likely familiar to everyone as the source used in the typical SPL competition. Sine waves are a periodic waveform. That is, these sine waves or test tones are quite simply a repeating waveform with equal intervals and amplitude in time. Music, in contrast, is very dynamic and transient. Music is a nonperiodic wave form. Meaning music is composed of sounds that frequently vary amplitude, vary in tone and last for varying periods of time. Most sounds and peaks in music last for very brief periods of time, many times only for a fraction of a second. Both sine waves and music have an "average level" and a "peak level". The peak level is the highest output level achieved by the tone or music. What we are concerned about is the difference between that average level and the peak level. And that difference is known as crest factor. Sine waves have a crest factor of 3db. Meaning the peak of the signal is 3db higher than the average level of the signal. Music on the other hand has a crest factor of 10db - 20db (or more) depending on the dynamics of the music and the amount of compression. On newer music, the compression is (unfortunately) typically higher reducing the dynamics and thus reducing the crest factor to the lower end of that spectrum. Higher quality recordings with less compression will be on the upper end of the crest factor spectrum with a crest factor of around 20db or more. The System Now that we understand a little bit about the music we're listening to, let's discuss how it relates to your system. So what does a crest factor of 10db or 20db mean? Well, we can use the formula 10*log(X/Y) to determine how much of a power increase is required to increase output by 10db and 20db. 10*log(10/1) = 10db 10*log(100/1) = 20db This means the amplifier must increase power by a factor of 10 to increase output by 10db and a factor of 100 to increase output by 20db. In other words, that dynamic peak of 10db will require your amplifier provide 10x the power over the average level. And to meet a 20db dynamic peak, it would require the amplifier output 100x the power over the average level. Sounds like a lot, eh? It is! So if you are using an amplifier with an unclipped power output capability of 100w, and you are listening to music with a crest factor of 20db then the average output you would be able to obtain from the amplifier and avoid clipping the dynamic peaks is 1w. The same amplifier with a crest factor of 10db, the average output would be 10w. What happens if we want to listen to our 20db crest factor music at a higher average level than just 1w of output on our 100w amplifier? Well, you certainly can.....but you will end up clipping the dynamic peaks. Going back to what we said before about the nature of music, it's very transient. Those large peaks will occur over very short durations of time and change rapidly. Due to various reasons our brain can handle some amount of clipping without negative audible effects. But it is also possible, depending on the amount of clipping, original crest factor of the music and frequency regions involved, etc, that this clipping could result in harsh or compressed sounding dynamics at higher output listening levels. This is because of the increase in distortion as a result of clipping, and due to the forced reduction of the level of the dynamic peak compared to the average level of the music. An undesirable result indeed. There are, of course, other issues involved with clipping such as potential damage to components such as speakers, but that's best left to another thread as it can be quite involved in-and-of itself. Headroom This leads us to the utility of amplifier headroom. And also the reason I'm a huge advocate of purchasing the most power your budget will allow. What is meant by the term "headroom"? It means having excess power reserves or capabilities available from the amplifier for use during those dynamic peaks to avoid clipping the amplifier and the resultant negative effects it can have on the sound of the system. The two ways of obtaining this headroom are as follows; The first is "headroom" inherent to the amplifier itself, the second is headroom allowed by purchasing an amplifier with higher power capabilities. For headroom inherent to the amplifier itself, we need to consider the way amplifiers are measured. Amplifiers power rating can be done in several ways. The first, and most commonly cited, is continuous average power (incorrectly called "RMS" power). This should be the output capabilities of the amplifier measured over extended periods of time at some distortion figure, generally 1% or less, at some supply voltage, generally 12V-14.4V. It is, however, possible to measure an amplifiers output on very short periods of time, typically fractions of a second. This is referred to as music power or dynamic power. For most typical amplifier designs, this will not change significantly enough from the continuous power output capabilities to really matter in the grand scheme of things. It is, however, possible to design an amplifier that has considerably higher dynamic power than it does continuous power output capabilities. One more extreme example of this is Rockford's 15kw amplifier with it's enormous bank of internal capacitors that can't sustain long term output support but can greatly increase power output for short term "bursts". Other companies have designed more practical applications of increasing dynamic power, but these are the exception and not the rule. Do not confuse the real measure of dynamic or music power with the fictional marketing term used by many low end companies, which in their lingo is essentially an ILS rating. That leaves use with the second consideration to increasing headroom; Buying an amplifier with higher power capabilities than we may think we need. Looking back at how power increases with regard to dynamic peaks, it's easy to see how this could be beneficial. Compare, for example, a 50w amplifier and a 200w amplifier. Let's just say, to keep things simple, that we are listening to music with a crest factor of 10db and we are listening at an average level that requires 10w of output from the amplifier. When those 10db dynamic peaks occur, they will require a 10x increase in power, to 100w. If we are using a 50w amplifier, then these peaks would require the 50w amplifier to output twice it's unclipped output capabilities.....which means we will be clipping the amplifier during those peaks, potentially leading to the ill effects previously listed. In this particular scenario, you reduced your unclipped dynamic headroom capabilities from the necessary 10db to 7db. On the other hand, if we are using the 200w amplifier and that 10db dynamic peak occurs, we are still well under the amplifier's capabilities....removing the worry about clipping and the resultant increase in distortion and compressed dynamics. Does everyone need a 200+ watt-per-channel amplifier? Certainly not. But it does explain why it makes sense to look for the amplifier with the highest power capabilities out of the viable options within your budget. All else equal (build quality, features, aesthetic value, etc) it's generally advisable to go with the higher powered amplifier. Where it can be avoided, there's no reason to make available power the limiting factor to the performance of your system. Allow yourself the necessary headroom when choosing amplification for your system. If that's a 50wpc amplifier or a 300wpc amplifier is a decision for you to make. Now, you may be thinking; But wait! My speakers are only rated at 50w, what in the heck will happen when they receive that 100w dynamic peak?! Well, the short answer here is that a speaker's power rating is typically a thermal rating based on it's ability to sustain that power level over an extended period of time. Again, due to the transient nature of music, those dynamic peaks are occurring over very short periods of time. Due to the short time frame of that dynamic peak, the speaker will quickly dissipate the heat. Speakers can handle much more power over very short periods of time than they can over longer periods of time.

No more discussion about someone's name. Let's get back to acting like adults and stick to the original topic.

The high pass is already set to 80hZ. The eq was set to flat when this was happening. We later set the gains higher as far as the upper end of the spectrum was concerned and turned the midbass down a little to tone down the "popping". Josh said that the sound cuts out every once in a while. I thought this might be the source of the problem but so far trouble shooting has not gotten us far. Keep in mind frequency is only half of the crossover. Slope also needs taken into consideration. If it is a shallower slope (i.e. 12db/oct as the Sundown has) then the frequency may need set higher to keep the speakers excursion under control while playing at the higher output levels that the OP is wanting. And again, sound deadening and better isolation of the frontwave & backwave (i.e. sealing the door) may also be helpful.

That popping was likely the mid reaching their excursion limit. If so, then increasing the highpass crossover as I suggested could help alleviate part of that issue. Do you know where the highpass is set now? Also make sure you don't have any EQ adjustments in the headunit (if it has any) turned up in level. Sound deadening & sealing the door would help increase their performance also. I would personally try intelligent application of sound deadening and sealing up any holes in the door to fully isolate the frontwave from the backwave prior to purchasing new speakers. For sound deadening, I would highly recommending www.sounddeadenershowdown.com If you have any questions about how many tiles to purchase or the best application/use of the product to obtain full performance from the sound deadening for your money, shoot Don an email and I'm sure he would gladly assist you.

How are the mids mounted? Cheap plastic OEM adaptor or a solid MDF baffle? Is the door well sealed and deadened or completely stock? Is there a level setting on the crossover for the tweeter, and if so where is it set? Yes, that quite possibly would affect the gain setting as the loudness would cause the preamp outputs to output higher voltage and probably clip sooner than when it is set to off. Also I would skip the DMM for setting the gain and do it by ear, if you wanted you could use the DMM after it was set to where you wanted just to help verify it wasn't completely out of whack. I would also try adjusting the highpass setting for the component set, a slightly higher crossover frequency might allow the mids to get a little louder without reaching their excursion limits as soon.

Unfortunately speaker sensitivity ultimately isn't going to be very helpful either. That is a specification rated at 1w of input, so it does not tell you which will ultimately be louder playing at higher power levels as there are many other factors at play. Frequency response, power compression, installation location and as a result off-axis performance, etc will all also shape how "loud" a given component set is in actual application. To Jammer: What exactly isn't "loud" enough for you? Do you feel it lacks any particular frequency region, or just not loud enough in general? I would honestly be a little surprised if you weren't able to get what you were looking for out of your current setup, possibly with some readjustments, as 125wpc should be sufficient to drive about any set of speakers past the point of listen-ability output wise. If it hasn't already been stated (as I admittedly didn't read the past 4 pages), can you describe your current installation as far as where the speakers are located, how they are installed, and the various settings thoughout the system?

It could only be considered useful in extreme situations where the fuse rating is nonsensical in comparison to the rated power......which is pretty much only an issue in brands already known to output far less than rated power.

Curious as to why they would ever think that some RMS calculation is possible. Hell even clamp meters aren't very accurate. Just something that was thought to be true. Personally, I had been told this by many audio shops as well as car audio boards. Multiply the total of the fuses on the amp by the voltage it receives and you will get a figure for the rms wattage. Nobody with any understanding has ever thought it to be true. One of those myths perpetuated through the ignorant masses.

No, you couldn't test it solely with a DMM. You would also need a test load and oscilloscope at minimum to actually do it correctly.

It depends on how the "knob" actually operates. Some of the external "bass knobs" are really just a volume control, so there's no hurt in using it and turning it up to 100%....and when doing so, the gain would not be reset. Others act like more of a true bass boost control, in which case the gain would need set with the knob turned to the highest position you would use it.

It would do nothing useful for you. As said, it wouldn't tell you if you were clipping. With music it would be jumping numbers so quickly you probably wouldn't even be able to read it anyways. And even if you did know how much power were going to your subs at any given moment (you wouldn't, but hypothetically speaking), how actually useful is this information? Not very.

The fuse rating will tell you absolutely nothing about the power output of the amplifier. Some people incorrectly try to use it as a basis for determining power output. But it's really meaningless. The only true way to know the actual power output is to bench test the amplifier.

I believe the CSP used XBL^2. IIRC the RE Destroyer that RE was selling for a while used the CSP motor. Should be a pretty decent sub.

How do you know?

Mechanical failure is when something physically breaks because either 1) there is either a malfunction in the driver due to manufacturing error (poor glue joint, etc) or 2) you exceed the physical limitations of the driver (i.e. overexcursion). If it moves, it can break.

The general "rule of thumb" is a gain of approximately 12db/octave beginning in the 60-80hz range. This is ofcourse not going to be accurate for any one particular vehicle, but is a general approximation. As M5 said, the best thing to do is to measure it yourself if you really want to know.

Hopefully this is a true 2nd coming and not an overhyped marketing campaign like some other companies have done recently *cough* Soundstream *cough*

Have you talked with Excessive to see first if it was a faulty alt? What are your actual amplifiers.....i.e. Brand & Model? What Fi subs? Do you listen to this system on a daily basis?

Again, why do you want to run 16V daily?

That sounds like a much more reasonable and obtainable description.