Another sealed sub question...

Hello!
Just a simple (and stupid) question...what would be the best 'real-world-money' sealed subwoofer a DIY'er can build...?
There's a lot of talking about...but :
- which driver...(I don't like long-throws)...?
- which amp and crossover...?
Should it have any equalization...?
In the first place it will need good (variable Fcutoff) xover and
fast, fast sound...for me 80 percent subs are simply slow...
Does anyone know what is Equalized Reflex that Pro Ac uses in its newest suboofer...?
What do you think about ScanSpeak 25W8555-01 in sealed, equailzed enclosure...? Or maybe two of then on the opposite walls..?


Cheers,

Fuzzy_logic
 
You might consider researching the Vandersteen subs. Richard uses small drivers specifically because of their low mass and speed... Unfortunately, I don't know which drivers he uses...

I've heard these and they are very good...

http://www.vandersteen.com/pages/2Wlit_intro.htm

http://www.vandersteen.com/pages/prod_info.htm

Also, another company that has been building subwoofers for a very long time is AudioPro. They were using multiple small drivers for speed literally 15 years ago... There stuff is also very good and very fast...

http://www.audiopro.com/

One last company that has very interesting technology is Bag End. This is what I use for the low end in my system. Their technology is patented and is they are the only ones who offer it as far as I know... It's very interesting because the idea is very simple and the bass is very fast. This stuff is used extensively in most mixdown studios for both audio recordings as well as movie post production houses. The sound is very fast and goes many steps lower than the best that's out there... I know that most are saying to themselves "yea right" but I'm telling you from first hand experience. Listen to them, read the reviews and look at the technology. It works... Explore around the site and read everything you can about the ELF technology...

http://www.bagend.com/what_is_elf.htm

http://ww2.bagend.com/bagend/elfguide13w.pdf

http://www.bagend.com/

Lastly, the "speed" is greatly affected by placement of the sub. For maximum speed, place the sub out from the rear wall several feet. You will notice that the bass won't be as loud due to the wall not acting as a horn, but the speed will dramatically increase... Also, make sure that the distance to the walls behind and to the sides of your subs (and speakers) is different. For example perhaps 3 feet behind and 2 feet to the sidewall. The point is not to use matching distances... Finally, in conversation with Richard Vandersteen, he firmly believes that downfiring drivers sound better and faster... I don't have as strong as an opinion on the subject but do have experience in one aspect. An older sub of mind had a downfiring 10" driver. Over time, the spyder and surround sagged from the weight of the cone and voice coil. I had to have the driver rebuilt not because it was blown but because of the sag... I know that some drivers are designed to prevent this, but if you think of the physics involved some sag will eventually happen... Just figured that I'd mention this so you were weighing all options as you're designing...

I don't have vested interest in any of the above companies...I just know their products and have experience with each...

Hope this helps,

Steve