One very important (and quality-increasing) thing to consider that you can learn from the pro industry is that it's almost meaningless to optimize to much for TSP tuning. The motor quality (distortion, power handling and BL linearity over the Xvar) is much more important than finetuneing box sizes and port tuning or trying to find a driver with slightly different TSP. When you're spending hundreds of thousand of Euros per system, these are not things that are taken lightly, so believe me - it's well tested in reality. A ported 32Hz tuned 40L system has the EXACT same group delay curve as a 60L 32Hz tuned box with the same driver - after you've EQ'd them to the same target curve. What you need to tune for is SPL output within your desired working range with all limiting factors included - Box size, Power, Excursion, Port airspeed. 3-5dB's of EQ is nothing nowadays, watts are cheap. At least a lot cheaper than good drivers :) The only time I take box-tuning really seriously nowadays is if EQ is absolutely, non-negotiably unavailable. Some customers really feel this way, even though you explain to them that both port tuning and box size (and also crossovers...) are physically the same thing as "EQ" - just realized in another manner.

Hi Nerijus, cool video. An interesting experiment in regards to the bandpass box can be done. In the German car hifi community there is something called a fortissimo bandpass. The idea is to build the sealed portion of the bandpass to roughly a qtc of 0.7 and then start of with the vented part being about double the size and tuning the box really high, like 65 to 70hz. You got to play a bit with the volume abs running frequency to get a constant rise with a massive peak at the tuning frequency. And then you set a fairly low low pass, somewhere between 30 and 45 hz with LR or BU 4th order. If done correctly your frequency response above the low pass flattens out completely, which means that you get incredible output with tiny power and because the sub barely has to move around the running frequency thegroup delay also becomes much smaller of an issue .

I live in Japan, and this speaker is not available here! I don't know why alpine don't sell the premium lineup

In a sealed enclosure, if you cut down the box below vas a little bit, how much the fs will change? how to calculate that? Isnt better to use the air as a suspension instead of stiff spiders, wont that make the driver more efficient? Driver design is very interesting

Just wondering, what do you think about the sub? Is there any sub around a similar price to this that you'd recommend over something like this for sq? I am also attracted to the looks haha...

Hello, I saw the Hdz-110 subwoofer video, I wanted you to guide me on the best box that can be made for a quality system, tell me the dimensions, of course, in the video, if I understood correctly, you said that you would see a port on it that you can use as SPL whenever you want, and every If you don't want it, you can use it as sq, please tell me the volume of the box in liters and its length, width and height in centimeters, thank you.

Why enclosure size matters in a ported box if there is a hole in it?

T/s parametere looks like false , how is it possible that re value be 6 while it has 2+2 ohm vc , also look at value of sd!!! 11-inch subwoofer has 700 cm2 sd .... according to size of cone it should be around 500 cm2