Where are the subs?

dbphd:
    "I’m skeptical of your last sentence. The Ayre preamp connects to the SMS-1 which connects to the subs. I never use subs without acoustic room correction."

Hello dbphd,     
     Millercarbon , clio09 and myself all have experience using 4-sub DBA systems in our rooms and know there's absolutely no need for mics, room correction or bass room treatments.
     However, it seems you're determined to use the SMS-1 with room correction in your new room.  I agree with clio09 that you should use what you're comfortable with but I'm not as confident as clio09 that you'll accomplish the same results from either a DBA with no room correction and a master SMS-1 for your two 15s and a slave SMS-1 for your two 10s (see the bottom of page 10 on your SMS-1 manual for setup instructions on this).
     As I stated on my last post:
     "My overall impression is that the SMS-1 and the DBA system have the same goal, to achieve accurate natural and smooth in-room bass response, but through different methods. It strikes me that the SMS-1 method is trying to simulate digitally what our brains do naturally with the DBA method.  
      The SMS-1 approach is attempting to smooth or even out bass peaks and dips in a room through room analysis using test tones and mics, digital conversion and processing along with parametric equalization. It's more proficient at reducing bass peaks than boosting bass dips since boosting all bass dips of various frequencies and decibels needs to be done more judiciously to prevent overstressing the sub or subs.
    The DBA approach is attempting to smooth out bass peaks and dips in a room through creating more peaks and dips and relying upon the proven psycho acoustic principle of our brains summing and averaging these peaks and dips which results in a perceived accurate and smooth in-room bass response. It's equally proficient at reducing bass peaks and boosting bass dips since boosting all bass dips of various frequencies and decibels requires no increased bass output from the sub or subs.
      I'm certain the 4-sub DBA system works like a charm without any mics, room analysis, room correction software or hardware, parametric equalization and room treatments."

      However,I've never used or heard a 4-sub DBA system configured through an SMS-1 and utilizing room correction so I'm not certain how well this method would work.  
     The reason I'm skeptical is because it seems to me that the two methods would be working against one another.  The DBA concept is based on producing numerous more bass peaks and dips in the room while the SMS-1 room control concept is based on reducing as many bass peaks and boosting as many bass dips in the room as possible.  
     I hope the net effect of this dueling bass response concepts results in an overall positive result but, having no experience using both at the same time, I really have no idea what the results will be.
     Hopefully, you'll have your two 15s repaired by the time the experienced clio09 arrives for a visit and you guys can figure out a good solution.  I'd love to join in and help out but I'm in Indiana and have no plans to be in L.A. anytime soon.

     Good luck and please repost here detailing how things worked out.

Thanks,
  Tim

Tim,

I appreciate your advice. Tony’s visit is motivation to haul the HGs-15s to LA for repair.

As I’m sure you’re aware, an SMS-1 emits a series of pulses through the subs that are captured by its microphone, evaluated, and equalization applied that mainly cuts peaks without amplifying valleys. The process can be for one or multiple subs, so I see no downside in using it. On the other hand, the SMS-1 remote includes an equalization defeat button making it trivial to try the array both with equalization and without.

I had a Marchand 4th order 80 Hz fully balanced passive high-pass filter built for use between the Ayre KX-5 Twenty preamp and VX-5 Twenty amp that I’m not now using. I might want to install that and set the low-pass to 4th order 80 Hz. I’ll trust Tony’s listening judgement on that.

db

@dbphd, We may have spoken about this before so forgive me if I am repeating myself, but have you tried a 100 Hz cut off? Does your Marchand have a high pass cut off as well or are you running the Kef’s full range?

I think for Casa Dorinda the system I would like to see you use is the Ayre 5 Twenty with the Codex, Sonore, and LS50s. Add 4 subs to that and be done with it.

Won’t head down that way until late July so that should give you enough time to get the subs repaired.

dbphd:
"As I’m sure you’re aware, an SMS-1 emits a series of pulses through the subs that are captured by its microphone, evaluated, and equalization applied that mainly cuts peaks without amplifying valleys. The process can be for one or multiple subs, so I see no downside in using it. On the other hand, the SMS-1 remote includes an equalization defeat button making it trivial to try the array both with equalization and without."

Hello dbphd,

     I have been looking through the SMS-1 manual.  I was under the impression its corrective equalization did both, cuts bass peaks and amplifies bass dips or valleys.  I'm not saying you're wrong, it's just that I remember a section warning that trying to correct dips/valleys of -6 Db or more could result in overdriving or stressing a sub. But now that I'm thinking about it, it could have been referring to manual adjustments and you could be right that the automatic equalization will not attempt to amplify dips/valleys this large.  
     If this is true, I think it's a positive factor in determining how well a 4-sub DBA and MS-1 combination will actually perform.  I'll leave it to you and Tony to figure out.
     I've just started reading the manual section, starting at the bottom of page 10, on  using multiple subs and how to utilize multiple SMS-1s in a master-slave configuration.  You owning multiple SMS-1s could be very useful.  
    I'm currently thinking connecting both of your 15s on one SMS-1 as a master and connecting both of your 10s on another SMS-1 as slaves might be the best way to set your system up.
     I've also been thinking about the best method for distributing your subs in your 19' x 14' room.  Can you tell me which wall you have your 100" screen mounted on, a short wall or long wall?  And whether you're willing to move the screen and reconfigure your room if it would result in improved system performance?
     Here's an example explaining why this could be important.  You guys may discover that the bass sounds better in your room with the 15s positioned about 8' apart along a 14' wall than along a 19' wall.  The reason could be as simple as the very long deep bass soundwaves (a 20 Hz wave is about 56' long, a 30 Hz wave is about 38' long and a 40 Hz wave is about 28' long) require an extra wall reflection for the entire length of the complete soundwave to exist in the room and be processed by our brains as a deep bass tone.  The 56' 20 Hz soundwave would be launched from the front 14' wall and need to travel the length of the room's 19' length, reflect off the rear 14' wall, travel the 19' length of the room again and reflect off the 14' front wall and travel another 18' toward the rear wall before our brains even process this now complete soundwave to be recognized as a 20 Hz tone.  This is just sort of 3 reflections for the soundwave to be heard.  If the sub was placed along a 19" wall, the same 56' long 20 Hz wave would require almost exactly 4 reflections to be heard. 
     Will this make any difference in the perceived bass quality either with or without room correction?  I'm not sure but you guys will probably be finding out.
    The ability to turn the SMS-1's equalization on or off as a remote function is extremely convenient and another positive factor in determining just how well a 4-sub DBA and multiple SMS-1 combination may actually perform.  
     Things are certainly looking good.  The results should be very interesting. 

Thanks,
   Tim