Zealot125

1080i (interlaced fields) and 1080p (progressive frames) are totally different. 1080i is functionally the same as 540p because the horizontal lines of resolution need to be overlapped in a temporal domain, therefore, 1080/2=540 lines of horizontal resolution when it is output. 1080p has 1080 lines of discreet horizontal resoulution and is therefore of twice the quality of 1080i. This is my rudimentary understanding of the concept. Others here will likely be able to present more advanced/more accurate descriptions.

Accelerometers can be miniscule in dimension and mass. There are even piezo-electric film accelerometers that are paper thin. I dont know what Velodyne uses, but I used that example to illustrate how miniscule they can be.

Just a bit of quantum indecision guys, the photons got lost on the way to the CCD. []

Alternatively, you could electroplate tin onto the ends. I realize that its nerdy, but I think that it would work well. Plus, Ive never electoplated with tin before, and frankly I am curious to see if it would work.

Uh, why not just do an infinite baffle?

That is quite the frightening monster, and is clearly capable of some MONSTROUS output. On the other hand, it really doesnt go too low. You would probably be ok if you just use it for music, but it might have a tendancy to sound slightly boomy. That and it would be downright sucidal to use that to its full capabilities in a relatively small home theater. If I might ask, how much do they want for it?

Not the best picture, but its the only one I could find. Should be an easy one.

For the money on a computer, the PMUs cant be beat. Good SQ, low price, good output, easy to use.

No offense at all but.....EWWW! You really should model and rebuild.

He plays Satan in "Constantine", thats all that I can recall

Yes, and the engraving should read: "Dedicated to the humblest man alive" []

Copy protection has never stopped anyone who ever gave it the least bit of effort. DVDs, Game CDs, etc. Ripping them is not difficult if you know what you are doing. I doubt seriously if a copy protection that is uncrackable wil ever be invented. So in the end it dowsnt really matter.

<-----------------John Petrucci Classically trained, but a rocker through and through. I find this combination of skills produces a memorable guitarist.

TheEar, are you just not reccomending the titanic kits, or the titanic drivers, because a ported DIY Dayton MKII 15" models out really well with and F3 of around 20 hz. The driver seems to be great bang for the buck. Still not too great for pipe organ music, but capable nonetheless.

You were letting me go on about the Titanic in my other thread without tellimg me that there is a better perfoming alternative that costs less money??? Shame on you! How could you, I am hurt! No, but really, should I consider switching to this different driver? PS Sorry for partial thread hijack...

Well, we dicussed this earlier, and actually wood glue is the better alternative to industrial adhesives like this Bulldog stuff.. As well as they affix objects, it is the wood glue's reaction with cellulose (wood) that essentially "fuses" the peices together. Start with 2 peices of MDF, end with 1. If you use adhesive, you still end with 2 peices of mdf, albeit powerfully glued together.

So what is the benefit of using a hurricane nut or T nut instead of simply a washer and nut?

Furthermore, this is a DIY thread about a project that I would personally enjoy. You are right I am nowhere NEAR to being an audio engineer, but I can sure as hell give it the best of my own humble efforts. If you arent going to be constructive, then what is your goal for these posts?

Wow, um, I didnt really understant where that came from... Are you angry because your enclosure is far less than ideal, or what is the problem. Dr. Whos point is 100% valid. T/S parameters can be measured to a very accurate degree, and are by far the most applicable variables by which to model subwoofer design. How do you presume that klipsch designs their subs, or how wilson designs theirs? - by starting with the cold hard numbers - thats how. There is a reason people use winISD over other programs- it is easy to use, covers all the bases, and does good math.

Jay I saw your post about hurricane nuts, but I am still confused as to their use. Could you elaborate? PS dont worry, I am installing trillian as we speak.

will do buddy, but i gotta install trillian first, but its late and I have some differential equations to solve for homework, so that is a project for another day.

Guys, this thread has turned out to be a fantastic wealth of knowledge - and some of the most fun reading that I have done in a week! Thanks a million for your dedication to accurate subwoofer construction. Only one little problem. I know we modeled the FR with that parametric EQ at 20 hz with a Q of 2 +3 dB, but the parametric eq on the sub only allows a Q between .1 and 1. So, I changed the Q to 1 and the FR seemed to improve even more. Is there something else I need to change or is this right? EDIT with a gain of 4 dB the FR improves even further, and with a 20 x 1.5 inch 25 inch long port, port air velocity is still about 28 m/s.

I am messing with some filters on WinISD. Is room gain 3 or 6 dB gain?

That all sounds fantastic, but this is my first endeavor into sub building and I want to keep it simple. One of my goals is to learn some woodworking skills as well. Unfortunately, my budget maxes out at about $550-$600, which fits this particular project well. I am pretty set on using this driver with a bas reflex enclosure, but I am also up for suggestions if there is a way to get more bang for my buck.

I looked in the list but still did not see the entry for the dayton subwoofer. I am using the alpha version, should I be using the older one? Also, what is the best way to secure the double layer of MDF together? Also, when speaking of the diameter of the flared port, are we talking about the narrow diameter in the middle, or the flared diameter of the ends?