Help finding a subwoofer

do you mind to elaborate on what you meant when you wrote preserving the damping factor at crossover frequency

When using active crossovers - which entails removing the passive in a multiway speaker - the amplifier is connected directly to the driver, so the damping factor of the amplifier is unaffected.

An idealized passive crossover has an infinite impedance at the crossover frequency. Hence zero amplifier damping. In the real world, the impedance is not quite infinite, but can be several multiples of the nominal impedance and thus driving the damping to zero. Look at speaker impedance graphs on Stereophile and you will see impedance peaks of 10x nominal. The phase response is horrible in the XO region.

Thinking of budget I would forego xo to the Mains. And thinking about the high level input the question arise if the the worse tube amp bass performance relative to solid state is due to interaction with speakers is it then less worse going into the subwoofer. If tubes mean bad bass then I would also have to forego high level input .

XO to the mains is trivial. A simple series capacitor correctly sized to the main amp impedance. Anyone can build one in an afternoon. XO frequency should be at least ½ octave above anechoic corner frequency.

See Simple HQ Passive XO

High level sub inputs are about the dumbest idea extant. People spend silly money on fancy speaker cables and then gum up the works with a "Y-cord"

Yate, with your SVS SB1000pro can you use the app for frequency response when you make the high level connection? soix makes a good sugestión that you may not be able to use on board DSP and high level connections.

I believe my Cain and Cain have just one resistor at input.

If one has a couple of subs in stereo a y cable splitter is not needed. Thoough I have read that both subs work with The sum of left and right signal to be able to cancel nods.

And a powered sub must deal with the amplifier to driver interface correctly.

Another part that makes me a total ignorant in the subject ask the question is how the input of a subwoofer is able to deal with signals from all amps in a high level input, does it not make a difference to the sub the differences in amps current, impedance tabs?

I should have said in 5e last paragraph when connected to a high level signal.

@alanpiga  the PB2000 to me is better musically. It just breathes and has such a presence. Makes sense, the box is huge by comparison, as is the driver. Funny thing is the internal amp in the micro is more powerful. I have read that folks seem to like the SB2000 more for music, reportedly faster and more musical likely due to being sealed as opposed to a ports on the PB.

Couple of variables to me that could be in play is my two rooms are quite a bit different. The basement room has loads of room treatment. Corner foam, stand alone traps and about half the back wall covered in acoustic foam panels. Living room is smaller and has no treatment at all. I think if I could have a bigger sub box in the living room I would have gone with either the PB2000 or the SB2000.