Fi sub as H/T sub?

[drewlrox 0]

Well, I went to lowes and their saw had way too rough of a blade to cut mdf w/o totaly ripping up the side. so i think im gonna just have to do it with a handsaw and buy a carbide blade. a family member of mine has a high end handsaw that will perform much better then mine. im thinking about trying to secure a strip of mdf alligned to the blade offset from the edge of the saw to try and make straight cuts, or just doing it free hand. not sure yet. i know a few people with table saws but none of them measure up to 38 inches

[drewlrox 0]

Turns out my moms boyfriend's friend owns a shop ans makes speaker enclosures,crossovers,towers, and complete systems for a living cant beleive i didnt figure this out until now. his shop is about 2 hours away so i arranged to meet down there and do all of the enclosure related things on the 28th!!! this shud make things much easier

[s_carter 5]

they should have had a nice 40 or 50 tooth blade there, that doesn't make any sense to me....

I make all my cuts with a straightedge and a circular saw with a 40 tooth blade kinda like this one. works great!

[s_carter 5]

awesome deal dude! that will help things along quite a bit! take lots of build pics along the way.

[drewlrox 0]

they should have had a nice 40 or 50 tooth blade there, that doesn't make any sense to me....

I make all my cuts with a straightedge and a circular saw with a 40 tooth blade kinda like this one. works great!

yeah its a really nice saw but he said there blades go thru tons of abuse and there not allowed to change it unless someone is sent out because insurance blah blah.

[drewlrox 0]

awesome deal dude! that will help things along quite a bit! take lots of build pics along the way.

My phone has an 8 megapixel camera and i always have it on me, also love to take pictures so ill take several throughout the building process!!

[s_carter 5]

oh you were talking about having them cut the wood for you, i thought you meant an off the shelf blade, haha, mah bad.

[95Honda 486]

Just a point on the dampening-

Poly fill is not going to do much with a vented box. The reason behind this that once you have properly designed the box (which you have) the only point of any dampening materials will be to dampening harmonics/mechanical noises. At the frequencies a subwoofer operates at, the material has little to no deampening effect.

The ideal way to dampen a vented subwoofer box (if you use any at all) is to line all the walls with some type of material that will attenuate the harmonics and mechanical noises, and leave the majority of the enclosure open, especially the pathway leading to the vent.

If you start adding a ton of polyfill, you won't really help dampen harmonics and noise as much as lined walls, what you will do is begin to alter the Q of the alignment and impede vent flow, which mor ethan likely will start throwing off your predicted response.

Robert Bullock, a pretty good reference on this, talks in detail in "Bullock on boxes" about the point of NOT using any dampening materials in subwoofer alignemnts due to the unintended changes in response they cause vs any benefit.

Full range boxes are complete different due to the fact that you must deal with all the mid/high frequency energy.

In the 100 or so successful vented subwoofers I have built, lining all the walls with 2-3" of fiberglass has seemed to offer the best results. I have tried everything from Black hole to home made crap with fiberous cotton/sand/latex mixes....

[s_carter 5]

Yeah, that is a good point, I use sound deadener or acoustical fiberglass for vented boxes, for some reason I was thinking of a sealed box. Check this company out, they have all kind of cool stuff over here.

[drewlrox 0]

I got my behringer amp, decided to throw it on my elt525 monitors to see how it sounded and it sounds amazing!!! only thing that confuses me is that there rated at 100wpc and there taking everything the behringer can throw at them with no distortion at all?!?!?! oh well im sure it outs out more past the meter on the front says because i never hit the limiter light at all.

[s_carter 5]

yeah if those speakers are 8 ohms, then you are not going to see a lot of power out of that amp due to impedance rise. but thats awesome to hear, when is your sub due in?

[drewlrox 0]

yeah if those speakers are 8 ohms, then you are not going to see a lot of power out of that amp due to impedance rise. but thats awesome to hear, when is your sub due in?

there a little under 6 so ya that makes sence, i was like... okay haha. the sub is due the 24 so this friday. i shud have the enclosure a few days after hopefully!!

[drewlrox 0]

Got my driver, wired it up in free air a just to see how my amp performs w/ my receiver pre out and i noticed the sub makes quite a bit of mechanical noise even at low volume, is this normal?

[Bob345 39]

Got my driver, wired it up in free air a just to see how my amp performs w/ my receiver pre out and i noticed the sub makes quite a bit of mechanical noise even at low volume, is this normal?

Yep, my q does the same thing. It's probably because they don't have a pole vent so there is more turbulence inside the motor. Once it's in a box, it's unnoticable. Any pics?

Edited December 30, 2010 by Bobobass

[drewlrox 0]

Sorry everyone ive been gone for the holidays the last few days, I bought 3 sheets of mdf today. tommorow I am going to a family members house who is experienced with wood working and making all of the cuts, before I make my cuts does anybody see anything wrong with my box plans? here are the winisd and sketchup files in a zip http://www.2shared.com/file/JocbNtV5/Q18_D2_Build.html . the box is 10 ft cubed after all displacements with a 3.5"x 26.5"x 47"(length) port for a tune of 21Hz. Should be fun thanks for all of the help everyone! especially Sam i dont think i would of been able to figure this all out without your help

[s_carter 5]

Looks good to me. Looking forward to the rest of the build!

[drewlrox 0]

Looks good to me. Looking forward to the rest of the build!

I sortta finished it last night minus the sanding and wood filling screw holes, I tried to get away without tnuts and I'm not positive what happened but it didn't want to mount great, only half the screws grabbed good and one like... broke or something. It plays fine but low notes let some air thru the driver. I'm going to just leave it weakly mounted until I get the t-nuts I ordered last night. I'm in school on my phone again and dont have enough time to upload pics so I will when I get home. Thanks for your help, I'm more then satisfied with the build!!!!

[drewlrox 0]

PICTURES!!!

[s_carter 5]

looks nice Drew, I bet it will be enough to blow your doors off their hinges when you get it all dialed in!

[drewlrox 0]

looks nice Drew, I bet it will be enough to blow your doors off their hinges when you get it all dialed in!

It sounds great without the driver properly mounted, I dont think the mount will make a huge difference but I definitely need to get it mounted soon to prevent wear on the baffle. parts express usually ships pretty fast.

[s_carter 5]

so was the cutout too big, or what happened with it? there should be plenty of wood for the mounting screws to grab into...

[drewlrox 0]

so was the cutout too big, or what happened with it? there should be plenty of wood for the mounting screws to grab into...

Oh idk, its just that mdf is sorta weak for holding screws and i needed alot of torque to hold the driver in and screws just dont work well.

[s_carter 5]

Well, it looks like a monster, man. I hope your neighbors enjoy the bass.

[lifelessheap 0]

Does anybody have any recommendations on a good amp to push this monster?

Behringer EP4000

[drewlrox 0]

Does anybody have any recommendations on a good amp to push this monster?

Behringer EP4000

lol, about 8 pages too late. Appreciate the input though. Im already pushing it with one of behringer's new EPQ2000's. Welcome to SSA!!!!