Musical subwoofer under $2000

I hate to offer another way, as you seem to be narrowing down options, but, in my opinion, using the Vandersteen subs would be best way to integrate a subwoofer into your system.

The use of a 1st order high pass filter doesn't introduce any delays in the time/phase of the signal. It also lets you amplifier do more by eliminating the demanding lower notes.

I have used other subs in my system and they just don't integrate as seamlessly nor easily as the Vandy subs.

The main constraint is that you need to buy the crossover (either fixed or the M5-HP which allows you to change impedance load from the amplifier). Older models like the 2w/2wq can be had quite reasonably used. The new Sub 3 has an equalizer built in, and can be tuned to the room.

Bob

@mofojo   Nice to hear a realistic direct experience.

I had an early version F113 in the house. When used with the early Velodyne DD Optimization the smaller F113 was surprisingly every bit as potent as the larger DD-18.

At the time both manufacturers were not only similarly priced but seemed to be on the same developmental timing trajectory. I too had a similar positive service experience just prior to the 2019 sale.   

@highend64, thanks for the heads up on Rational Acoustics. I was not aware of this and will be looking into it. I use mostly Omnimic V2 available from Parts Express.

@gdnrbob, yes Richard Vandersteen's rather unique practice of using a woofer below it's natural resonance frequency works extremely well. I have not seen mention of anyone else using this approach.

High passing the main speakers makes so much sense I'm surprised it is not more widely adopted. As you say: it unloads the amp essentially providing more headroom and reduces speaker IM distortion.

I have a DIY line stage where I can select between output terminals and have one of them with a single cap and resistor soldered in place forming a simple line level high-pass. For those interested who do not want to butcher their kit just connect it to either end of your interconnect cables.

The value of cap depends on the input impedance of the power amp or the internal impedance of the tape loop in your integrated amp.

Google PLLXO (passive line level cross over) for tables and simple formula. This is not only the least expensive way to do this but also probably causes the least damage by avoiding extra cables and their associated connectors.