During a few years of my childhood when Bob Ross’ show was on PBS, Saturday mornings offered a bit of that Christmas-morning excitement for me.
That’s because, as the gentle ‘fro-topped painter began each episode, my dad would hit “record” on our VCR to capture the steps and instructions for the week’s painting.
After watching the show in real time, we’d move the TV into the garage and set up our easels and get out our Bob Ross-branded paints and brushes, and we’d meticulously recreate the artwork du jour.
That’s the kind of thing I want for this subwoofer project. I aim to serve as a guide and bring it within reach of anyone — dads and sons included.
Like a painting you can admire, this is a project that will provide the family with a musical machine that will be enjoyed by everyone, daily, for years to come.
We began last week with the first step: buying the kit from Parts Express online. Again, a quick search on their site for “Dayton dsp subwoofer kit” will show you the options, and the 10-inch version is our focus. But the 8-inch kit will apply as well, because my most useful advice concerns the implementation of the DSP.
The kit comes supplied with easy-to-follow instructions for the cabinet build, and it requires glue and clamps if you have them. Clamping is important for fusing the wood panels together to create a solid box. Sound is all about vibrations, and the low tones of a subwoofer vibrate immensely. This thing is going to create 30-foot-long sound waves, so it needs to become one solid piece.
If you don’t have clamps, check out double-headed nails, which will allow you to tack the boards together after the glue is applied and remove them easily once it dries.
After gluing, instructions become simple: Add dampening absorptive material, attach the drivers and plate amplifier with screws, and voila! You’re done.
But we are not done, my friend. The next stage of the subwoofer build will be most important. Using modern DSP, we will look at the subwoofer’s strengths and weaknesses and we’ll overcome the weak parts digitally. By the end of it, this thing will be without flaws, and your friends will be without their jaws as they behold your sonic creation.
I’ll wrap this segment up by touching on some of the technology involved in our sub. There are three subwoofer-looking drivers that come in the kit, but only one of them is active — the other two are what we call “passive radiators.”
Just like a radiator radiates heat, these radiate sound. The way they do it is by vibrating along with the pressure waves inside the box from the active one doing its thing.
Picture the novelty toy shaped like an animal that you squeeze and the eyes pop out. Do you know what I’m talking about? Apply pressure, and the inner jelly stuff squishes out the available pressure-less holes.
That’s what’s going on here. When the active subwoofer kicks out, these two passive radiators kick inward. And vice versa. The result is louder sound and better sound. We’ll take that a step further as we explore DSP next week.