It's sort of like going back to pre school and telling Steve the paste is for adhesion, not for eating, but he just keeps smearing the **** on his sandwich, day after day.
Mark confirmed the air spring distortion as well, and while nobody ever made it out to be a huge distortion, it - combined with the reduced amount of power an IB needs to achieve the same levels at low frequencies as a smallish sealed box - gets back to why I said an IB will perform similarly to a smallish sealed with less distortion in the lower frequencies. No more, no less. And this is why we CAN look at Ilkka's testing of the TC2k ported vs sealed and get a very clear picture of what a SLLT vs IB will do with minimal extrapolation required. 3 pages down the drain
Exactly how did Mark 'confirm' air spring distortion?
Ilkka's test of the ported TC2K vs what sealed? You mean the defective TC2K that has its output numbers in parenthesis? Good example.
In all your thousands of posts about comparing whatever it is you deem comparable to make whatever point it is you keep babbling about, there is not a single real comparison, driver for driver. Not one.
I challenged you to show the modeled comparison between the LMS-5400-18" sealed vs the ported version. By all means, extrapolate. I'm still holding my breath.
It would be one thing if a comparable design could actually get there with a linear FR, adequate headroom (120db+), and decent distortion levels, but instead, when a smallish sealed design is forced (EQ'd) to try and reach that low, it not only can't do those things, but it takes away a LOT from the reproduction of the most common bass ranges. Large and low tuned ported on the other hand basically leaves the reproduction of 35hz+ alone (intact) and slowly adds clean output as frequency decreases until below tuning. It's corny, but I'm still impressed by the concept when I think about it. So maybe the size isn't for everyone, but you can't argue with the performance advantages.
Here, we have the Stevie Gems, all in one paragraph.
1) Sealed L/T has NO EQ ABOVE 35Hz. Did you get that Steve? I can repeat it until you do, if you need me to, which seems apparent that you do need me, and a dozen other people to, over and over and over.
2) Your recent favorite example, the ported TC2K: LINEAR FR?? Down 20dB at 10Hz with compression on the 105dB sweep? You're right, it's corny.
3) 120dB?? You mean 4 of them? And, 10 of them won't get you 120dB at 10Hz, your own magic number.
4) Port compression at 100dB. Wow, it's miraculous performance.
5) 100% THD at 15Hz. More miracles.
6) 16.5Hz tune. Is that the 'L'? Man, that's what, a whole 1/3 octave lower than TV's first DIY ported 12" sub. Big improvement in 9 years.
7) TV kicked that sub's tail in a smaller box, smaller driver, 1600 watts less amp, more linear response, more output, same port compression, lower extension, less THD, better driver protection, variable tune, better looking, better warranty...
Maybe you should be asking TV for pointers instead of arguing with a guy who has more clean output, 10dB more output at 10Hz and 30dB more output at 5Hz in less space than 4 of the PB-13 Ultras...for the same money.
You can't even use that TC2K ported sub for firewood where I come from, but it's a benchmark performance for Steve, as he references it every day...vs 'extrapolations'.
LMS-5400-18". LLT it and get back to me.