My experience adding subwoofers to 2 channel

I forgot to mention that clio has also eliminated 4 of the 5 primary reflections that cause comb filtering in the bass. 
Another way to look at this is that the bass linear array is just a more specific DBA system. It will always require 4 or more drivers unless you listen in a closet.

Hello clio09,
     Wait a minute.  What's your plan?
I thought your plan was switching to a line array with larger subs. Four new subs using 10" drivers sounds like your planning a dba.

Tim
  

I use low pass and high pass filters in my active crossover, Linkwitz-Riley 4th order 24 dB slope. One reason this was chosen is that we wanted to keep deep male vocals out of the subs. The other reason had to do with the resonance of the 8" drivers which we wanted to keep above 100 Hz. This is the reason for a 0.3 cu. ft. box which is stuffed tightly with cotton batting. The last reason has more to do with Roger Modjeski’s ESL design which only goes down to 100 Hz but that is irrelevant to me as I use the Acoustats which he modified to create greater dispersion, but left the rest alone, sort of ;)

I should also mention that the speakers are 4 ft. from the wall behind them, 18" from the side walls, and about 94" apart, which is the same distance to my listening position.

clio09:
"My subs were built a while back, mijostyn helped me set them up for optimal performance in the line array. His subs have quite a large footprint, as do his speakers which are probably the best Acoustat model in my opinion. They line array per mijostyn is actually a semi circle as opposed to all of the subs being against the front wall of the room. A very interesting set up and one that does require some attention to detail. I appreciate mijostyn’s patient with me.

In my room the DBA did work well for my needs, and it wasn’t a difficult system to set up. My only nit was that my room constraints didn’t allow me complete freedom to place the subs anywhere I wanted. The sound was quite good though. I am embarking on building 4 new subs using a 10" driver and look forward to going to the audio show in Long Beach to hear Duke’s Swarm in person."


Hello clio09,
     
     I'm having difficulty following along with your posts.  From your post quoted above, it seems you're switching from using a distributed bass array (DBA) to a line bass array system for your Acoustats and with mijostyn's help.
     Then, in the very next paragraph, you state you're starting to build four new subs with 10" drivers and you're looking forward to hearing Duke's Swarm DBA system, which happens to utilize four subs with 10" drivers just like the four new subs you're about to start to building, at an audio show in Long Beach.       
     Don't you agree this might be a bit confusing to a reader, especially when you just stated you're in the process of switching from a distributed to a line array bass system?
    But the confusion continues with your latest post from5/27/19:
"I use low pass and high pass filters in my active crossover, Linkwitz-Riley 4th order 24 dB slope. One reason this was chosen is that we wanted to keep deep male vocals out of the subs. The other reason had to do with the resonance of the 8" drivers which we wanted to keep above 100 Hz. This is the reason for a 0.3 cu. ft. box which is stuffed tightly with cotton batting. The last reason has more to do with Roger Modjeski’s ESL design which only goes down to 100 Hz but that is irrelevant to me as I use the Acoustats which he modified to create greater dispersion, but left the rest alone, sort of ;)"

     Now you're discussing 8" drivers in 0.3 cu. ft. boxes stuffed with cotton batting that only extend down to 100 Hz?  Would this even be considered a sub and how are these 'mid-bass woofers' even relevant to either the DBA or the line-array bass system you're using?

     Can you please clarify?

Tim

@noble100 if it wasn’t clear let me try to clarify it for you.

1. I’m building subs with 10" drivers for use as either a DBA or line array. It’s nice to have choices.

2. My active crossover has LP and HP filters set at 100 Hz. So the HP output sends signals 100 Hz and above to the panels and the LP output sends signals below 100 Hz to the 4 subs. Direct drive amps power the panels, a solid state amp or moderately powered tube amp with good damping powers the subs.

3. My current subs use 8" drivers in a tightly stuffed 0.3 cu. ft. box. This was done to insure the resonance of the driver was above 100 Hz. If I set the crossover points to 150 Hz on my filters this would be an issue but since I’m using 100 Hz and anything below that is sent to the subs this falls below the resonance so it’s a good thing. I should note that this was designed by Roger Modjeski for his ESL speaker system and the subs easily extend down to 30 Hz. If you don’t know who Roger is look him up, his experience and reputation speak for itself.

I tend to think at this point you just might have an issue with anyone who isn’t completely devoted to the DBA as you are. At least I can say from experience I have used the DBA and now trying a line array I have the ability to compare and decide what works best for me. My comments regarding Duke have more to do with my respect for him as a speaker designer, having owned his speakers at one time and exhibited his speakers at shows, than anything to do with DBA. Anytime I am at an audio show and Duke is exhibiting I make sure to spend time visiting the room. It’s always interesting to see what he is up to.