The Dali Spektor 2 are rated at -
Frequency Range (+/-3 dB) [Hz] : 54 - 26,000 Hz
That should be within the working range of the Crossover on the Subwoofer. So, I would set the Sub to cross in the roughly 50hz t0 55hz range.
You might want to edit your post, it say -
I want to add this AMP .... SW150. You want to add a
Subwoofer. Not that big a deal, I'm sure we all figured it out.
As suggested above, as the Front Speakers naturally roll-off, the Sub will come in and pick up the slack on the low end. This is what you would do for the smoothest integration.
That would be the starting point. However, some like to overlap the Front and Sub speakers. This creates an artificial, and somewhat unnatural bump the bass in the overlap area. Whether you like that or not is up to you to decide. But to start with, set the Sub at the natural roll-off of the Front speakers. Then you can work from there.
Now, it is possible to get High-Pass filters
(crossovers) in the 70hz to 100hz range. I know you can get them in Europe but I don't have a source right now.
However, just to illustrate that such products exist, here is a link to a USA source -
80 Hz High Pass 8 Ohm CrossoverConvenient crossovers that work great in any application requiring economical, flexible filtering. Also for use in car stereo installations with component speaker systems. Low pass, band pass, and high pass models complement woofers, midranges, and tweeters...
www.parts-express.com
100 Hz High Pass 8 Ohm CrossoverConvenient crossovers that work great in any application requiring economical, flexible filtering. Also for use in car stereo installations with component speaker systems. Low pass, band pass, and high pass models complement woofers, midranges, and tweeters...
www.parts-express.com
Steve/bluewizard