My experience adding subwoofers to 2 channel


My Kappa 9 speakers are rated to 29hz and they sound pretty good in my 18x24 room...powered by McIntosh mc1.25 amps...l was looking for another layer of bass to enhance the sound..my first experiment l took my SVS pb16 ultras from my theater room and tried them first...it sounded terrible,didn't blend well..couldn't hear a difference until you turned in up then it rattled the room apart........my final experiment worked..l used 4 Velodyne minivee subwoofers(1000 watt rms class D sealed 8 in.) and after hours of calibration l hit it......lve got the bass response that exeeded my expectations. ....l should have done this along time ago....can anybody tell me of another subwoofer that may work even better?
128x128vinnydabully
Hello Tim,
i have the dual 12” F212v1. I just got the 21.0LX the early this month after waiting 6 months for them. Comparing to the F212v1 which I have for the last 6 years, I like the 21.0LX better as it makes the overall sound more engaging. Big doesn’t have to be loud, the output level gain have to be lowered so they just disappeared into the room like the F212v1.
Unlike the F212v1 which have the variable 360 phase adjustment, the 21.0LX have delay adjustment in ms by the software DSP. My system sound best with only the 21.0LX. With the 4 subs, I think there is a timing issue between them which smear the sound. I have no ideal how to set them to be in phase with each other and the main speakers.
All available space on the left and right wall are racks with the hifi equipments. The back wall are tube traps from floor to ceiling and blue ray cabinets. On the front wall I have the fix screen for the projector, and half tube traps below the screen. Also floor to ceiling tube traps on the corners of the front wall and a cradle mounted center speaker.
I am not planning to move as I am over the 70s, my last hangout. Hahaha.
Hello khiak,

      Well, you have four very high quality subs which you should be able to position and configure into a very high quality 4-sub distributed bass array system for music and ht.  
     I'm willing to assist you in this process but I want to warn you it's going to take some work and trial and error experimenting to properly position and configure the settings. 
     If you'd like me to assist you, I just need to know a few more things before we get started.  It sounds like you have a screen and projector for video setup on the opposite 18 ft walls. So, I need you to confirm this and describe the rest of your audio/video equipment:

1.  All your receivers, amps, preamps,surround sound processors, turntables, cd players, video players and any other hardware you use.
2.  All equipment and storage racks.
3.  The main speakers, center channel and surround speakers you use. 
4.  Any room treatments you currently use such as carpets,bass traps and absorption or diffusor panels.

Tim

noble1001,287 posts05-23-2019 4:00amHello khiak,    
    I'm willing to assist you in this process but I want to warn you it's going to take some work and trial and error experimenting to properly position and configure the settings.
Very nice offer.

Researching khiak's Canadian Funk Audio 21.0LX subwoofer's their enclosure seems to be well crafted and similar to another successful subwoofer design. 

Tim, I'd suggest obtaining more information on the parameters of their DSP process. Specifically, if they're able to line out their DSP'd signal into the F212s. I was able to do this with an F113v1 from my Velodyne DD and the F113s integration and output improved in my room. 

The F113 is a very fine subwoofer but its crossover and manual adjustability seemed to be a shortcoming in my experience. JL Audio currently markets version 2 processing and a separate CR-1 Crossover component which I have no experience with. 

I would definitely NOT sell your F212 v1s. Good luck with it.
Hello m-db,
     Thanks for your information.  I'll look at the manual on Funk Audio's website to learn more. 
     He has four very high quality and expensive subs.  The 4-sub DBA concept works exceptionally well even without room control. Do you use 4 subs in your system and room control?
     If so, I'm interested in learning what specific additional bass performance improvements you noticed beyond the typical bass quality improvements gained from using the 4-sub DBA system.  In other words, what specific bass quality improvements did you notice after applying the room control?

Thanks,
  Tim
   
Hello Tim,
Many thanks for your kind offer to help me in the setup of the 4 subs in my music room. 😃😃😃

After viewing Audiogon forum on getting better bass performance with 4 subwoofers in a room, I decided to give it a try. So I added two 21.0LX to my existing two F212.v1 early this month. Instead of adding another two F212v2, I decided to go for 21 inches woofers as I have never heard the bass from such woofers in my life. I have owned the F212v1 for 6 years but I have to say the bass of 21.0LX is awesome.

I have a fix Stewart movie screen frame 94” X 55” at the front wall about 5 ft behind the tweeter of main speakers. The bottom edge of the screen frame is 27” from the floor. From the left edge of the screen frame to the left wall, there is a ASC full round tube trap from floor to ceiling, similarly on the right edge. From the bottom of the screen frame to the floor, I have half round ASC tube trap horizontally. I have 2 half round ASC tube trap mounted on the ceiling between the 2 corners full round tube trap. There is a set of 3 half round tube traps mounted on the ceiling across the width of the room above the main speakers.
A Revel voice 2 center speaker with mounting pedestal sit in front of the movie screen with the F212v1 at each side. The subs are about 2 ft from the edge of the Center speaker.
The Kharma Exquisite Reference 1E Signature main speakers are 7ft apart and the F212v1 is about 1.5ft behind the main speakers inner side. Between the main speakers are 3 rows of 5 mono amps and preamp power supply. Left row is Goldmund Telos 600 stack on top of each other for left main speaker bi-amps, middle row is Goldmund Telos 600 mounted on the bottom of 2 deck rack for the center speaker. The power supply of the Goldmund Mimesis 22S sit on the top deck of the rack, right most row is Goldmund Telos 600 stack on top of each other for the right main speaker bi-amp.
The Goldmund Mimesis 22S Signature preamp sit on a rack in front of the Rack for the center  speaker power amp. 
On the right wall 1.5 ft away from the right main speaker are 3 rows of 3 deck racks where two Mark Levinson N332 for Revel Embrace surround and Vienna acoustics back speakers, Marantz MM8077 for  four Beale Street ICA6-BB height speakers and two Bose wide speakers. Marantz AV8802A processor, Pioneer DVL-919, Dream Vision Sealer 3, Lexicon RT-10, Phillips BDP9600 and Panasonic DMP-UB900 are located.
On the left wall 1.9 ft from left main speaker, sit the 21.0LX follow by a rack with 2 deck for the Reimyo CDP-777 and DAP-999EX and finally the door to the room.
On the corners of the back wall are full round ASC tube traps from floor to ceiling with a 70”X16” wall mounted Blueray cabinets on their side and 3 columns floor to ceiling full round ASC tube traps between them.
The right and left walls above the rack height are space with ASC sound planks. At the wall just beside the main speakers are custom wall mounted reflective towers.
The main listening chair is 7ft from the main speaker and 12ft from the front wall.
The JVC RS-65U projector is mounted to the ceiling directly above the main listening chair.
Hope all these info are helpful. I wish I can send you photos which are much better.

😃 Thanks 
khiak