My experience adding subwoofers to 2 channel

@noble100, The amplifier is the Music Reference RM-200, 100 watts per channel, damping factor of 10, can drive a 2 ohm load (it’s a favorite amp among some of the Martin Logan crowd). The other amps I use are vintage Luxman and Accuphase amps. For solid state I don’t bother with Class D, was never consumed with mega watts, and much prefer a high current Class AB design which is more suited to my needs. Also, the 8" drivers I use don’t need much in the way of damping.

As for my subs being feeble, sure no problem, we all have our opinions. Glad I could amuse you. However, I don’t listen to my music loud, I don’t do HT, and I’m not consumed with the last octave in the bass. As I mentioned, the system was designed by Roger Modjeski and his reputation speaks for itself. The cabinets for the 10" drivers are going to be a unique design and the bass will extend lower, but again, bass has never been the primary focus for me. My set up does exactly what I need it to do and so far it’s doing it better as a line array than the DBA. Although I find both set ups to be very useful in creating smooth, fast, and un-smeared bass.

BTW - I hope you are not using that Dayton Audio kilowatt amp for your swarm.

Tim, actually clio has a 12 foot wide sub woofer which goes deeper than just a single sub. Remember drivers closer together than 1/2 the wavelength of the highest frequency you want to reproduce act acoustically as one driver. Larger subs will allow you to go deeper as long as the enclosures are appropriately designed. I am not sure were this speed thing came in. Bigger drivers with appropriately sized motors are not slower but as the size and mass of the cone increases they become more difficult to control and keep their motion pistonic. All this is outlined by the driver's parameters which we use to design enclosures. I do not like ported sub woofers. They are more efficient and it is easier to get them to go lower but I have not heard one that to my ear is as accurate as a good sealed driver. The problem with sealed drivers is that you have to force them to go down using equalization and a lot of power. But the drivers we have today can easily handle it and with an amp with DF over 500, using a slightly over sized enclosure (Q around 7) you can get some really amazing bass. I personally see no use for drivers over 12 inches. In either a DBA or linear array system with 4 units you will never run out of drive in anything smaller than 40 X 20 feet especially if you keep the drivers up against a wall or corner.
Clio, I did not know you had an M60. What a tricky guy!. Just remove the Acoustats and put the Quads right down in the same place, same angle. Do both DBA and Linear Array and let us know what you think. The quads are point source which means they will not project power (volume) as well as a linear array. As you move back from the listening position the woofers will become progressively louder than the Quads. Down the block you will just hear the woofers:) As long as things are in balance at the listening position you are in business. Even in a DBA arrangement if you can keep the woofers closer than 5 feet apart that would be a benefit. Other people with lower cross over points could get away with more distance.
The 2+2s are nothing more than stacked 2s without the base. The angle is the same. If you could find another set of 2s you could make 2+2s out of them. I toyed around with the idea of making 3+3s but eventually I will go with Soundlabs. I think what Roger is doing is is rolling off the high frequencies at the outer edge of the Stators to make the panels effectively narrower as the frequency goes up which would increase high frequency dispersion. Making 2s or 2+2s disperse is IMHO fruitless. Just stay in your listening position and enjoy. 

Hello Tim,
I still do not know how to send the video to you. As so I am not savvy, please take me on a step by step. Thank you.

Hello clio09,

      I've read about your Acoustat 2+2 electrostatic speakers mainly in the Stereophile review attached below but have never heard them myself. Based on this and their specs I've come to believe we're both looking for similar improvements in our system's bass response, namely a little more deep bass extension and improved deeper bass dynamics and impact.
    Your Acoustat 2+2 electrostatic panels have a bass extension limit of 28 Hz and my Magnepan 2.7QR planar-magnetic panels have a bass extension limit of 35 Hz. Fairly similar specs that would indicate they both would benefit from a sub system that would provide a little more deep bass extension down to the audible limit of 20 Hz and improved deep bass dynamics and impact.  
    If this is the case, which I know it exactly describes the deep bass I thought was missing in my system, then what is required is a supplemental bass system that provides bass extension down to 20 Hz, has the reserve power to provide life-like bass dynamics and impact that are felt as well as heard along with the bass not being perceived as disconnected, slow and lagging behind the sound from the main speakers.  
     I've found this last quality of providing bass that is detailed, smooth, dynamic and fast enough to blend seamlessly with our detailed, smooth and fast panel speakers is the most difficult but one of the best things a DBA system does.  It seems like you're now discovering that a custom bass line array can also seamlessly integrate as well or even better than a DBA.  Very interesting to know and I'd like to learn more.
     Btw, I am using that Dayton class AB kilowatt amp for my swarm.  I feel like you're setting me up for something, but I'll bite anyways and ask.  Why should I not use it?


Thanks,
  Tim 


https://www.stereophile.com/content/acoustat-22-loudspeaker

Rix, it is impossible to isolate a driver putting out low bass. The pressure wave itself is what makes the whole house vibrate, not the woofers connection to the house.
clio you want to handle Tim. I'm tired of talking to myself.
millercarbon you just gave some of the worlds finest speaker designers the middle finger. I think you should read acoustics for dummies before you start spouting off about what is or is not possible.