I am new to self-build audio. And the reason I came into it is a weird issue I have when the house is way too easy to excite by any shaking of a speaker in the 40-70 Hz range, especially if it touches the floor, but walls also have the effect. (I don't get any audio below 40 Hz; I have a Pioneer SX-315 AVR with its included 5.1 speakers - I really use 2.1 - and there is a high pass filter there at 40-45 Hz).
If I hold the sub on my outstretched arms the noise t the rest of the house does not happen. So this is about mechanical shaking.
The sub also does not sound well at all
So I want to build my own "sub". Not strictly what serious DIYers call a sub, as it needs to cover 45-200 Hz. The crossover is built into the AVR and can not be changed apparently, Moreover I am not yet replacing the satellite speakers. I do not need a lot of power at all, I'm listening from about a metre and don't do "heavy" music. What I need, however, is that the sub not shake *at all*, to avoid exciting the house.
And on this forum I found a discussion of a design that works like that, with vibration cancellation. I am not allowed to post links but the topic is called "PA380 PPSL design by LTD02".
I can not however just copy the design as I don't nearly have the space like that! Nor do I have the power requirements. This is a personal space listening thing, I can do with a pair of 6.5" to 8" drivers. And I'd like to have it comparatively compact too, though I understand that it has to be bigger than "just any" box for the same drivers.
Unfortunately I do have to go all the way up to 200 Hz so that has to be taken into account too.
I would really appreciate advise about designing a PPSL or other vibration-canceling box, and selecting speakers for it of course.
The best I know so far is a simple "box with speakers on both sides", which I could calculate as small as 20 L if I can get Dayton Audio DC160-4 drivers. I can turn one speaker around and in reverse polarity to make it PPSL (eliminating distortion is a nice thing when I want to listen at low volume and get all the details).
But I am interested in more advanced designs where perhaps the drivers are closer to each other, thus making vibration cancelling more effective.