DIY n00b...upgrading existing subwoofer with new driver?

[vi edit]

Sub in question was a dirt cheap ($100 markdown) KFL 12" sub that I picked up a few years ago to hold over for a while between some long distance moves. Never got around to getting anything nicer.

I've got a room that's almost 3x bigger than what I originally had in an older house and the paper thin, traveless speaker in this cabinet just can't fill the 2600^3 foot room I'm in now.

I'm on a rather limited budget (new baby and iminent daycare bills uhg!) but would like to increase my thump in the house.

The cabinet is a dual front ported 3/4" MDF box with a 200 watt amp. (Don't know if it's 8 or 4 ohm...is there a way to check?). It's about 2.3 cubic feet in volume, so a decent sized box.

Here's the pics:
http://pics.bbzzdd.com/users/viedit/subfront.JPG
http://pics.bbzzdd.com/users/viedit/subback.JPG

Can I just grab a 12" Titanic sub from Partsexpress and drop it in there and get a decent upgrade in volume with a better speaker?

http://www.partsexpress.com/pe...fm?&Partnumber=295-404

 

[sdifox]

I don't think it works that way, cabinets are matched to drivers, you change the driver, you have to modify the cabinet. Try here

http://www.diysubwoofers.org/

 

[montypythizzle]

I say do it. It is a great frame for another sub. That 150 dollars should make it a pretty nice HT sub. Keep in mind it will be an upgrade. Certainly more power handling and of course you can BUILD a box if you want... in the future..

 

[heyheybooboo]

You need to verify 4 / 8 ohm.

I'd take that 200-watt amp and build a new sub - with 2 speakers. You could find 2 10's for what you want to spend. Some specs even list enclosure volume ...

 

[PurdueRy]

Originally posted by: vi_edit
Sub in question was a dirt cheap ($100 markdown) KFL 12" sub that I picked up a few years ago to hold over for a while between some long distance moves. Never got around to getting anything nicer.

I've got a room that's almost 3x bigger than what I originally had in an older house and the paper thin, traveless speaker in this cabinet just can't fill the 2600^3 foot room I'm in now.

I'm on a rather limited budget (new baby and iminent daycare bills uhg!) but would like to increase my thump in the house.

The cabinet is a dual front ported 3/4" MDF box with a 200 watt amp. (Don't know if it's 8 or 4 ohm...is there a way to check?). It's about 2.3 cubic feet in volume, so a decent sized box.

Here's the pics:
http://pics.bbzzdd.com/users/viedit/subfront.JPG
http://pics.bbzzdd.com/users/viedit/subback.JPG

Can I just grab a 12" Titanic sub from Partsexpress and drop it in there and get a decent upgrade in volume with a better speaker?

http://www.partsexpress.com/pe...fm?&Partnumber=295-404

May or may not work. A sealed cabinet would make this much easier to do. Finding a driver to match a sealed cabinet is mostly dependent on a driver that just has a similar specs. Finding a better driver that works with a prebuilt cabinet and the ports is much harder.

 

[Renob]

May or may not work. A sealed cabinet would make this much easier to do.

I dont think so, when you use a sealed cab you need much more power that 200w amp of his will not be even close enought to drive the Titanic driver.

Build yourself a nice cab tune it to 20Hz and your amp should be enough power.

I just built this box in the link below I rounded all the corners with a router then put 4 coats of truck bedliner spray on it and it looks killer.

Box Build

I used the Elemental Designs 4in port and got me a Elemental Designs 12in driver for $100
13Kv.2 Driver

And OMG this things ROCKS it hits low and has a crazy amount of output!'

BTW Im using a Dayton 240w plate amp from Parts Express

With the $60 you save getting the 13Kv.2 over the Titanic you could buy the Port, the one sheet of MDF and the 2 cans of spray on truck bed liner woot and have a rocking HT Sub oh and Elemental Designs has a 5 year warranty just like the Titanic drive.

Building a box like the one from the link above is CAKE, I had Home Depot make the cuts, then found a friend with a rounter to cut the holes for the port and dirver then round the corner off on the box, I had so much fun I got me a nice new table saw and router this weekend, going to build a DIY center speaker next then some new mains woot for DIY!

 

[Rubycon]

Originally posted by: vi_edit

Can I just grab a 12" Titanic sub from Partsexpress and drop it in there and get a decent upgrade in volume with a better speaker?

http://www.partsexpress.com/pe...fm?&Partnumber=295-404

You can do this but don't expect a breathtaking increase in sound. It could even be worse! Speaker cabinet design is fairly complicated. It probably would work better with that size box if the ports are blocked off. Tuning to a very low frequency requires longer ports (or smaller ports) and is always a challenge because smaller ports whoosh and larger ports have to be long making the box look funny. (if they stick out)

Even if the replacement driver is a good physical match (TS parms) the amplifier may not be up to the task to drive it decently and use its potential. It's all fun though.

 

[Muadib]

I can't quite tell from your pics, but is your sub the KLH ASW12-200? If it is, thats a 8 ohm speaker, and you can't use that Dayton.

 

[vi edit]

Originally posted by: Renob

And OMG this things ROCKS it hits low and has a crazy amount of output!'

Building a box like the one from the link above is CAKE, I had Home Depot make the cuts, then found a friend with a rounter to cut the holes for the port and dirver then round the corner off on the box, I had so much fun I got me a nice new table saw and router this weekend, going to build a DIY center speaker next then some new mains woot for DIY!

From that forum link it looks like you were unhappy with the results. Did you ever figure out what was causing your low output?

Was it a problem with the electronics or driver, or was it a placement problem in your room?

 

[vi edit]

It looks like it's actually a 4ohm setup.

http://www.epinions.com/pr-KLH...2_Home_Audio_Subwoofer. I'm intrigued by the eD setup.

I could always buy the speaker, drop it in and see how it works. If I'm not happy I could throw together a cabniet for it on the cheap.

 

[Renob]

From that forum link it looks like you were unhappy with the results. Did you ever figure out what was causing your low output?

Yes yes the problem was me, the guys over at the AVS forums helped me out, oh and by the way when I was posting at the link above I had the cheaper oem driver ED was selling, not to say it sucks just never figured out my problem while it was in my box I now have the very nice 13Kv.2 in it now.

Here is a link to the thread at AVS

Sub Fix

 

[Operandi]

Throwing a driver in a box in hoping it sounds good is a very good plan or use of money.

Building a box isn't that big of an expense so I would determine your budget and build a box around whatever you can afford. There are plenty of documented designs you can follow and lots of knowledgeable people that will help you if you want to come up with your own enclosure. You can reuse the plate amp from the KLH if you want but $150 will get you a really nice 300 watt Bash amp.

 

[montypythizzle]

IDK, if that box says it will go to 20hz I would DEFINITELY do it.

 

[Excelsior]

It's about 2.3 cubic feet in volume, so a decent sized box.

Thats quite small though. Anyways, do you know the length/diameter of the ports?

 

[Operandi]

I should point out that the Dayton Reference series is currently on sale. These are some of the best subs out there for the money.

 

[vi edit]

Originally posted by: Excelsior

It's about 2.3 cubic feet in volume, so a decent sized box.

Thats quite small though. Anyways, do you know the length/diameter of the ports?

I actually recalculated the volume more accurately. It's more like 2.9 c/f. Ports are 4" and run about 11.5" deep.

I'm really considering the Dayton Reference now and trying my luck at it.

 

[Operandi]

Originally posted by: vi_edit

Originally posted by: Excelsior

It's about 2.3 cubic feet in volume, so a decent sized box.

Thats quite small though. Anyways, do you know the length/diameter of the ports?

I actually recalculated the volume more accurately. It's more like 2.9 c/f. Ports are 4" and run about 11.5" deep.

I'm really considering the Dayton Reference now and trying my luck at it.

If you don't want to build a new cabinet I would model they Dayton (and/or other drivers you are considering) in your box along with the ports and see how it dose. You really don't want to be making blind guesses.

Check out the DIY section of the HT Guide forums, you'll find lots of helpful experts there.

 

[Excelsior]

Originally posted by: vi_edit

Originally posted by: Excelsior

It's about 2.3 cubic feet in volume, so a decent sized box.

Thats quite small though. Anyways, do you know the length/diameter of the ports?

I actually recalculated the volume more accurately. It's more like 2.9 c/f. Ports are 4" and run about 11.5" deep.

I'm really considering the Dayton Reference now and trying my luck at it.

That sounds like a pretty high tuning frequency...If you did go with the Reference driver, the HO would be a better option for such an enclosure. But there are most likely better drivers for this situation due to the enclosure size and tuning frequency.

 

[vi edit]

I did end up buying the 12" HF 4ohm Dayton Reference. I'm going to drop in the existing case and see how it works.

If it sucks I'll bust out the shop tools and work on a 4.3 c/f cabinet since that seems to be the ideal volume for that driver. I wanted a down firing sub anyway. I'll just set up the cabinet for that application. I really don't want my daughter using the sub as a kick plate at some point when she's old enough to crawl/destroy things.

 

[Operandi]

Originally posted by: vi_edit
I did end up buying the 12" HF 4ohm Dayton Reference. I'm going to drop in the existing case and see how it works.

If it sucks I'll bust out the shop tools and work on a 4.3 c/f cabinet since that seems to be the ideal volume for that driver. I wanted a down firing sub anyway. I'll just set up the cabinet for that application. I really don't want my daughter using the sub as a kick plate at some point when she's old enough to crawl/destroy things.

Again, just guessing isn't a very smart way to go about this.

Modeling a sub is pretty easy and the results are usually pretty reliable since low frequency sounds are pretty predictable. You can model it yourself with something like this (it's not very difficult) or enlist the help of some experts. The DIY section of the HT Guide forums I linked to above is a great place with lots of very smart helpful people.

 

[montypythizzle]

PFFT, what about those premade boxes for subwoofers?? Why would they make those premade if they weren't going to sound HALF decent.

 

[PurdueRy]

Originally posted by: montypythizzle
PFFT, what about those premade boxes for subwoofers?? Why would they make those premade if they weren't going to sound HALF decent.

They make premade boxes in multiple volumes. You pick the volume closest to the ideal. You then add ports/amp for your particular application. He's using a box with the port already in place and the volume already decided.

 

[montypythizzle]

Originally posted by: PurdueRy

Originally posted by: montypythizzle
PFFT, what about those premade boxes for subwoofers?? Why would they make those premade if they weren't going to sound HALF decent.

They make premade boxes in multiple volumes. You pick the volume closest to the ideal. You then add ports/amp for your particular application. He's using a box with the port already in place and the volume already decided.

No, I am talking like car audio and stuff. They either make bandpass, ported, or sealed. Pretty much. Put subs with large magnets in there and instantly you are called a gangster and are hated by all elderly people.

 

[PurdueRy]

Originally posted by: montypythizzle

Originally posted by: PurdueRy

Originally posted by: montypythizzle
PFFT, what about those premade boxes for subwoofers?? Why would they make those premade if they weren't going to sound HALF decent.

They make premade boxes in multiple volumes. You pick the volume closest to the ideal. You then add ports/amp for your particular application. He's using a box with the port already in place and the volume already decided.

No, I am talking like car audio and stuff. They either make bandpass, ported, or sealed. Pretty much. Put subs with large magnets in there and instantly you are called a gangster and are hated by all elderly people.

Car audio people generally care more about BOOM than balanced audio accross the frequency spectrum. The bigger the boom and the more the trunk rattles...the "cooler" it is.

 

[Jugernot]

How did it turn out Vi? I've got a 12" budget sub that I'd like to do the same thing too... it's a downfiring 12" Advent sub with two rear ports. 150w I think, which isn't much, but works good for me. It's breaks up a bit when the loud low stuff comes on screen.