My experience adding subwoofers to 2 channel

I have the 12 inches subs for 6 years. The 21 inches subs added this month of May. Room is small so limited choice of placement.

Thanks, Tim for your help 

Hello khiak,

     What are the dimensions of your room (length x width x ceiling height)?  What are the brands and model numbers of your subs? 

     You can definitely achieve very good bass response at a single dedicated listening seat with 2 subs. Using the 'room crawl method', described to avanti1960 earlier, in a sequential manner (first sub#1 and then sub#2) is probably the best way to position them.
      In my experience, 2 subs will provide much better bass performance than 1 but in my opinion 4 subs will provide the best bass performance since line array sub configurations are not well suited for small rooms like distributed array sub configurations are. 
     The 4-sub DBA system concept works incredibly well in virtually any room and actually is perceived as making a small room seem like a larger room.
     The key to a DBA system being such an exceptionally high quality bass solution is the use of 4 subs; the brand/model, size, power, price and type (self amplified or passive) are much less important than the fact that there are 4 of them active in the room.  There are also no requirements that all subs are identical and subs of varying driver sizes, power, prices, types and bass extension are viable.
     If you have a smaller room, however, I'm curious why you chose to add 2 subs with large 21" drivers when adding 2 more subs with 12" drivers is more logical and physically suitable?

Tim

Hi Tim,
The room length 18 ft, width 12 ft and height 9 ft. The subs are JL212v1 and 21.0LX Funk Audio.

The main speakers are 7 ft apart and the JL212 sit about 1.5 feet behind the main speakers inner side. The main speakers is 5 ft from the back wall.

The main listening chair is 7ft from both speakers and 12 ft from the front wall.

Three feet behind the main chair are a row of 3 chairs.

A 21.0LX sit on the left wall 3 feet from left main speaker with the driver facing the right wall.

Another 21.0LX sit near the corner of the right wall 9 feet from the right main speaker with the driver facing the left main speaker.

The acoustic of the room is designed by ASC of Seattle.

So much discussion on 4 subs in the room, so I want to hear how 4 subs sounded in my dedicated room which is for 2 channel and home theatre. Why 21 inch driver, I never hear how 21 inch driver sound.

The rest of the wall space are occupy with racks and equipments and tube traps.

There are no other location available for the 2 21.0LX.


I have no idea how to go about to setup/calibrate  the 4 subs optimally.

Any help appreciated. Thanks.

khiak

Hello khiak,

     Those Funk Audio 21.0LX are beautiful subs but they're really meant for a larger room.  If you live in an apartment, your neighbors are going to hate you if you start using those in your room.  If you really want to use those in your room, you'll need to keep them turned to a low volume to work well in a 4-sub DBA.  I currently think the best solution for your room size would be 4 subs with single 12" drivers.  A few more questions:

I'm having trouble looking up the JL 212 V1, is the model# F212 V1?
Do they have single 12" drivers or dual 12" drivers?

Would you be able and willing to return the big Funk Audio subs to achieve better overall bass in your room?

It sounds like your main speakers and rack are along the long 18 ft wall with your listening chair, with 3 seats behind, along the opposite 18 ft wall.  Is this correct?

Are you planning on moving to a bigger place or home soon?

Thanks,
  Tim