While I'm waiting for Mark to cut into some raw metal and get these puppies built, I thought I'd post some idle musings I had on my commute this morning. I've been using ported subs for a long time (again, a ~6cube 19Hz tuned original Adire Tempest and a ~1.5 cube 24Hz tuned SDX-10) and I'm pretty used to the sound. I haven't properly calibrated them or set any EQ in our current living room, so there can be a little boominess at times, but they do a good job of rumbling as needed down low.
I've never heard a powerful sealed sub in person. I convinced myself a long time ago that I wanted to try something like that for my next sub project, and it looks like I'll be able to carry out my plans with a pair of UXL-18s. And now is when the hesitation kicks in. What if I'm a "ported guy"? I know that, all things being equal, ported subs will have an advantage in output down to their tuning frequency. More is better right? Should I be directing my efforts to just make "the most sound" that I can?
Well, let's take a step back first. First, I have a quick WinISD comparison of my two current subs and a single theoretical sealed UXL, as planned at 3.556 net cubic ft, getting approxinately 1,200W from half of an iNuke6000. (Ignore the orange lines, that was for my brother's project).
As I mentioned way earlier, looking exclusively at displacement, I think a single UXL (yellow) has more than twice the displacement capacity than my existing subs have combined. I'm not sure how to mentally sum the output of the pink and blue subs, but I think that even a single sub in this configuration would provide an upgrade. Would it SOUND like an upgrade? I'm not sure. I'm sure that from 20Hz and down it would be improved.
BassThatHz mentioned that he's heard the SDX-10 and the UXL-18 and that, comparatively, the SDX is like a tweeter, which I was glad to hear. There would be no question if it was my only sub that I would be crushing it with this upgrade. At least I'm glad to see that the UXL is significantly higher at the Tempest's tuning frequency, and well above it at it's peak of 70Hz. More reassurance. I won't even add EQ to this model, because it seems to be a clear win (even without adding the second UXL). OK, good.
Now my second issue... how much am I leaving on the table by going sealed vs. ported? Let's see. Now, I don't have unlimited space to put these things, so LLT is not an option. I did a quick model using about twice the size (7 cubes) and tuned to 16Hz.
The ported sub seems to have an advantage from about 48Hz and down, which is kind of an important area. Cone excursion just squeaks over xmax in the ported model at 10Hz, so that shouldn't be a major concern. Now, my secret weapon with the sealed sub... EQ. Theoretically (let me know if I'm getting this wrong), the sealed sub can handle more power by selectively applying some EQ to shape the response curve more to my liking. Ideally, I'd like to figure out a Linkwitz Transform that suits my subs, but I'll wait to measure in room before getting too far into that. Even using just 2 PEQ filters (as shown in the model), I'm able to bring it up to a more comparable result. The filters both keep boost to only 3dB, and cone excursion just barely comes above xmax at around 16Hz then dips back under.
The ported sub still has a 3-4dB advantage between 11 and 26Hz, but we're a lot closer. And working with half the size. I'm still getting 7dB more than I was from the Tempest at 20Hz, and I'm not even modeling the pair of UXL's. I was able to obtain a very similar result with an LT and a high pass at 10Hz to keep excursion reasonable. I guess what I have to ask myself now is "is that good enough?". I suspect that it will be. Does the sealed model's advantage above 26Hz mean it will feel "tighter" or give it more "punch"? Those traits are typically assigned to sealed subs (or that they sound more "musical"), are those attributes just typical of sealed enclosures in general? Do they exist at all? I know, this is getting flaky. And I'm about out of mental capacity.
- will my big ass sealed subs sound better than my current menagerie of mismatched ported subs, and will I be happier with the smaller sealed and EQ'ed enclosures rather than going ported again? I hope so. Does sealed have a "better" sound quality? Does a sealed setup provide more "punch" or "slam"? I'm drifting again, I need to step away...