help needed with HT DIY sub choices

[boogs]

I've been looking around on the net for the last couple of weeks for a good (meaning affordable, decent SPL and quality) subwoofer driver and i've finally come to a conclusion; i have no idea which one to choose!

First off, my HT is in my basement (which i've been finishing) and occupies only part of the total space. The HT is not fully enclosed but has a half wall on one side and is open on the other (see attached pic for a very crude drawing). I've got about 400w x2 available (into 4ohms) and have been looking at a pair of 15" high excursion woofers (Titanic, Soundsplinter etc). At present i have a pair of 12" diy subs i built a several years ago which still sound OK considering the woofers used (Kicker Solobaric - yeah i know, but they were free at the time!), but i am pretty sure they will not have the grunt necessary to fill the HT with acceptable levels of quality bass.

So i've come here looking for help and advice. I'd like to stay with sealed cabinets (for sound quality and safety factor) and under 3 cubic feet per enclosure - and i guess i don't have to stay with 15" subs either - if 12" subs could do it, that would be OK.

Thanks!

Scott

NB: I live In Kitchener, Ontario, Canada and ideally was hoping to find a company (online or not) that's located in Canada so as to avoid HUGE brokerage and shipping costs!

[RobWells]

These guys are in Canada:

http://www.creativesound.ca/

Say they sell adire's new stuff, but it all looks out of stock.

Rob.

[David Gatti]

The 12" Peerless XXLS look really tasty and are very popular and easy to obtain. Hard to beat in terms of value/performance.

http://www.diymobileaudio.com/forum/...read.php?t=842

[noah katz]

"Hard to beat in terms of value/performance."

For about the same $ you can get the TC Sounds TC2+ with 19.3mm xmax vs. 12.5 for the Peerless.

It also has a shorting ring and low distortion like the peerless.

http://www.oaudio.com/TC2_PLUS.html

[David Gatti]

Hard to disagre with you there Noah, though the Peerless looks a bit better above 100Hz.
Lots of comparisons here:
http://www.mfk-projects.com/woofers.htm

[boogs]

Thanks very much for the suggestions so far - if anyone else has any ideas/opinons, let me know!

Scott

[BobEllis]

A few thoughts -

There was a thread recently where GRollins (IIRC) said that his early long throw sub drivers exhibit a real world rising response, with a pretty big hump 80-100 Hz. This may or may not be true of current generation drivers, and Adire claims it is an artifact of the measurement technique in their Tempest white paper.

With most of the long throw drivers I have modeled, you'll need a bunch of EQ or a Linkwitz transform for deep bass in a sealed cabinet. Not necessarily a bad thing, just something to be aware of.

Zaph says that in his experience low xmax woofers sound better. He's talking woofers, not subs though. Applying this observation to subs makes sense to me. If you're only moving 1 mm, your distortion is likely to be lower than 15 mm, even with all the good stuff like XBL2 and Faraday rings and a 34mm xmax.

As you know, low frequencies require lots of displacement to reproduce at HT levels. If you are going to limit excursion to keep distorion low, then you're going to have to go to big drivers.

I am sure that there is some pride of ownership kicking in, but I have never heard a 12" sub that I have liked, and very few 15" subs do it for me in anything but the smallest room. My subs use the long out of production JBL2245H 18" pro sound driver. I have a pair in a room about the same size as your basement and 750W available for each. They are each in an 8 cubic foot ported cabinet tuned to 24 Hz, with a variable Q equalizer that allows flat in room response to 20Hz or so. I haven't heard anything that comes close to their impact and they are great for music, too.

So, without recommending any specific driver, my recommendation is to use the biggest drivers whose cabinets you can live with, and lots of them. Four 15" subs would not be too much in that room, and it gives you the opportunity to come close to the "optimum" placement that the Harman sub placement white paper recommends.

[boogs]

Hi Bob

Thanks for the White Paper reference - i've not heard of it before and i just finished skimming through it. So...unless i'm willing to increase the power i have available, there's no point in buying higher dollar, high x-max subs (20mm+). I would assume i could start looking at some OK subs with moderate power handling whose enclosures would best fit with the space i have and still manage decent LF extension.

Am i on track? Any other suggestions from any other members?

Thanks!! The info has been invaluable so far!

Scott

[boogs]

So i had a quick look around again at some psuedo-affordable 15" subs. Parts Express certainly has lots to choose from and while shipping would be pricey, there's nothing in Canada that comes close that's readily available.

I'm thinking perhaps this woofer http://www.partsexpress.com/pe/showd...number=295-190

Any other suggestions appreciated!

Scott

[BobEllis]

A bit of a catch 22 there - almost all drivers will need EQ. A mere 6db of boost is 4x the power. Efficiency, small box, bass extension. Choose any two. That's the reason those super xmax subs require so much power to reach xmax - they traded efficiency for extension.

I got some some relief from the power requirements of my subs, since their midband efficiency is 94 dB/2.83V. My mains are 88. So to keep up my sub only needs the same power as the mains, even with 6 db of boost. I have excess power, but it won't be so excessive when I plug the ports and go with a Linkwitz tranform requiring 17 db boost.

I'd say buy the biggest, best driver that you can. If it comes down to a good 15" or a top 12", go for the 15" and add more as money permits.