Prepare before you begin!!!

[texfrazer]

I wanted to share with everyone a good piece of advice that I should have followed when I started my DIY sub - Consider all of the angles before beginning a DIY project!!!!!!

It was going to be an awesome sub: I purchased a couple of vifa 12" drivers and got their data sheets. I calculated the box size and the port size. Next, I calculated the crossovers, purchased the capacitors, etc. and wired them together.

I constructed the box out of 3/4" plywood with internal bracing (having taken the bracing and internal depth of the drivers into the calculations for the box). I installed the drivers, the crossover, the back panel with external banana connections and hooked it up to my system. Overall, the box was approximately 8 cu. ft. in size.

The first cd I put in sounded really good. There was a notable increase in the bass output. The second, more bass heavy, cd sounded good - until I turned up the volume. It was at this point that the whole thing fell apart (not literally, just audibly). With the volume turned up, the drivers were bottoming out. After a lot of research and a lot of reworking of the sub, I came to the realization that the drivers were designed to be woofers, not subwoofers.

It's at this point that the wife has started asking questions about what the point of all of this was. Unfortunately, I have had to admit that the point has effectively been to spend a decent amount of money and a LOT of time teaching me to plan better.

Therefore, I wanted to share this with everyone - read everything you can before you attempt any DIY project. 90% of the time (this is something that I didn't want to admit), using a pre-planned DIY project (one someone else has completed and perfected) will work better than one you plan yourself - especially if you are only someone who dabbles in these sorts of things. This isn't to say that people shouldn't try, but start with plans that are known to work instead of trying something entirely new.

Anyway, best of luck to everyone attempting a DIY sub. I've had to resort to an SVS and be content with my DIY speakers. I'll do a write-up of those soon (they're a success story!!!!).

[Josuah]

Little confused. Why did you have to build a crossover? Did the drivers model correctly in software?

[texfrazer]

I built a crossover because, at the time I started, I was running an older Kenwood KR-X1000 receiver. This receiver has a sub out, but when it is engaged, it crosses all speaker outputs and sends them to the subs. As I have large mains that can handle a good bit of bass accurately, I wanted the full signal sent to them, while having the sub handle the really low stuff. Therefore, I had set up a low pass filter in the sub box and sent the full spectrum signal into the box where it was crossed.

Yes, I know, this was not ideal. And yet another reason why I posted the topic - though I didn't think of it when I was doing the initial post. We can add: make sure you understand how all the pieces will work together before setting up a DIY project so you don't have redundant systems attempting to accomplish the same task, albeit through separate processes. More wasted money!