Best subwoofers for my enclosure?

[JSantiago]

I was cleaning out my parents attic and found my dads old speaker enclosure from the 90s. Two towers with 2 15" pyle drivers in both. They still make sound, but nowhere near what I want due to years of decaying in the dust. I've looked around online and everything seems like it's really expensive or for car audio. 

Just looking for some good speakers that'll fit into my enclosure that's not gonna cost me like $1000 for all 4. Any suggestions?

[SantiagoManager]

parts-express.com is a good resource to find replacement speakers and speaker building.... 

What you really need to do is find the specifications of the old drivers then get the drivers that match the closest. If you take them apart hopefully you can find some model numbers on the back. Once you have the information find the one that matches the closest on their woofer selection guide. 

[SantiagoManager]

They are usually pretty good about helping you out as well if you call them. 

The other way to handle it if you can't get the woofer specifications, you can measure the internal volume of the speaker cabinet and then get a pair of 15" woofers that are designed for the same dimensions, but then you will still need to worry about SPL matching with the tweaters/midrange/horns in the cabinets.