95Honda

Just remember, port area has nothing to do with box volume and everything to do with driver displacement. If you are running designs and see an increase in output when you change port area (especially making it smaller) it is because you are manipulating something else unintentionaly. When you make a box smaller you make it less efficient, 100% of the time. It isn't that the driver likes the smaller box better, it is that you have lowered system efficiency with the by product of increased mechanical power handling. It will never be as loud as a larger more efficent box with proportionaly less power due to thermal compression. If you are modeling, shoot for lowest vent velocity possible while keeping you port a managable size, that really is all there is too it. It has nothing to do with the volume of your box...

The higher the system impedance the less current is drawn from the source. Ohms law. Remember, most amplifers are constant voltage in nature, they source the required current into the load to keep the voltage at a set level. The current they source depends on the load impedance. Amplifiers have frequency response. I design and build amplifiers. Clipping itself doesn't create heat. I did a comprehensive test on this almost 8 years ago here: http://www.forceaudi...ng-effect-test/ Sorry, the graphs were deleted. I have probably spent more time researching this than anyone on this, or any other car audio site. What you don't (and most other people) understand is, that when you properly set the last gain stage in a signal chain for maximum voltage drive without hitting the rail limits (clipping) with any type of test equipment, it is completely useless 99% of the time as you can still manipulate many different stages farther up the chain. My mind is probably more open than most. I pointed out the common missconceptions in this thread. I am sorry if I offended you, seriously.

#1 amplifers made today have resonably flat frequency response and do not "put out more power at higher frequencies" #2 clipping does not increase heat, more power does #3 the only thing to lower heat it to lower power #4 every gain setting tip in this thread is meaningless, O Scopes are useless in every situation posted on here. Just a few points... You turned the volume down somewhere, that is it.

If you don't need a ton of output than you would be fine doing a standard vented or sealed box. Don't need a marine driver for th emost part. Just look for something with a rubber surround, poly/aluminum/heavily treated cone and preferably an aluminum frame. Look at one of the Dayton HF 12s.... You could use something like window screen if you want to keep the bugs out...

^^ Easy to work with (machine) also......

Do you need a fair amount of output? I ask because outdoor audio really takes a hit on the bottom end. You don't get any room gain... Most outdoor subwoofers I have built have been vented, most 4th order bandpass and horns. I would stay away from a sealed alignment, unless of course you aren't worried about output. Honestly, 150 watts and a single driver in a seale dbox won't go really far. As far as the enclosure, is it going to get humidity only or get directly rained on? If it is just humidity, you can use most materials if you build it right. My in-laws have a set of 2-ways mounted above thier hot tub in a sun room (green house). I used Adire 4.5" midbases and Audax tweeters. It is a vented alignment, so air can get inside the box. The boxes are MDF, but I primed the inside with 3 coats of Dupont snadable primer and the outside is finished with Formica. I also used stainless mounting hardware and gold plated terminals. Everything soldered and the joints were cleaned and coated with conformal coating. It has been almost 8 years, the only thing that has changed is the copper phase plug on the Adire drivers isn't as shiny as it used to be, not turning green, but opaque looking... For a sub, look into a lab horn if you have the room, build it out of marine grade plywood and get it shot with line-x.... You could spray it with a hose every day and it would be fine... Hope this helps...

1" x 2" Aluminum bar stock will have no voltage drop...

I would build a spacer....

30Hz T-line for a 12 will be about 7 ft3 externally and have less SPL than a standard 4th order vented.. Food for thought..

The RMS rating of the sub has absolutely nothing to do with output, SPL, etc....

Location of the port will not change enclosure efficiency. It will load the cabin different, and that may give you an increase (or decrease) in output.

You guys realize the AWG has little to do with the size here? Strand count and construction are going to be your major factors in overall size, not AWG. Taking measurements of differerent wires with different strand construction is pointless, you cannot compare them. The brands like KNU look bigger becasue they are smaller individual strands and are loosely constructed, not because they have more copper. The Welding cable is smaller because it has larger strands and more efficient construction. The only real way to determain the AWG is to measure the diameter of a single strand and then count how many there are. Unless you do this, you have no idea what the AWG is.

Thanks for the info guys.

I am going to install a sub/amp in a 2000 Accord EX this weekend. Has the factory CD player in it. Does anyone know if that will have a power turn on/powered antenna output to switch the amp on/off? I don't want to wire a switch or run it off ignition... Also, no PAC TRUNK-LOC or anything like that in the build, amp has high level inputs, and that is all it will get... Any help would be appreciated guys... -Mike

I was hoping that wasn't the case...

Don't waste any money on CCA.

Port area is based on power and driver displacement. You need to model to figure this out. It has nothing to do with enclosure volume. Any other method to calculate is BS...

Just model for Qtc around .8-.9 if you don't want to go by everyone's info.

Of course it does. Vs. a non-clipped identical signal of same voltage amplitude. But this has nothing to do with blowing a driver. Let me put it this way, if you have a driver rated at X wattage, any more than X will blow it (thermally). That is it.

Clipping won't hurt anything, and your gain knob will not prevent you from putting out max power. This is ahuge missconception and gets more people in trouble than helps. Bottom line is, you can get full power out of any amplifier (up to and into full clipping) with just about any H/U with the gain at any setting. Additionally, too much continuos power kills a driver. It doesn't matter what the waveform.

The RMS has nothing to do with anything mechanical. It also has nothing to do with how much a drivers needs, at all. It is one of the most overly emphasized but irrelevant spec.

^^ Nobody is thread jacking. OP had a lot of questions.

You can clip all day and not blow the sub. That has nothing to do with it. That being said, you will be able to both thermally and mechanically blow that sub with an AQ2200 (or any amp that will do an honest 2KW) if you try hard enough. Again this has nothing at all to do with gain settings or clipping, you just need to remember that you will have enough power to ruin that sub....

As your subs get hotter, thier impednace increases and they draw less power for a given voltage...

CCA isn't fine, it is a marketing gimmick.... If it wasn't a gimmick, they wouldn't clad the aluminum with copper and price it appropriately as aluminum cable....