"with no audible impact on sound quality from the mains"
That is half of the million dollar question. The other half is getting a sub to blend with the mains at the crossover frequency and getting good placement to avoid the boom!
Certainly there are two way active crossovers that would go between your pre and amp. This is probably the "cleanest" way to go. Merchand, IRD audio, Paradigm make some of these. Price used $150 to $600.
Hypex sub amps have variable high and low pass filters (24db/Octave) so you could look for those subs or use one in a DIY. The Rava is the only sub I know that uses one.
The other option is to let you mains run full range, find the natural roll off with a spl meter and a test disc and bring the sub in just below their natural roll off.
Hope this helps,
MaxCast
That is half of the million dollar question. The other half is getting a sub to blend with the mains at the crossover frequency and getting good placement to avoid the boom!
Certainly there are two way active crossovers that would go between your pre and amp. This is probably the "cleanest" way to go. Merchand, IRD audio, Paradigm make some of these. Price used $150 to $600.
Hypex sub amps have variable high and low pass filters (24db/Octave) so you could look for those subs or use one in a DIY. The Rava is the only sub I know that uses one.
The other option is to let you mains run full range, find the natural roll off with a spl meter and a test disc and bring the sub in just below their natural roll off.
Hope this helps,
MaxCast