Subwoofers and Phase Question For You Sub Experts


I use a pair of Dunlavy SC-3 speakers, known for their time/phase coherent crossover design.

When the stars align the speakers completely disappear and there’s a sense of space and 3 dimensionality that I’ve heard from few other speakers/systems. It’s easy to destroy the illusion with things like poor placement, poor setup of room treatments, etc.

Adding subs to the setup is both a blessing and a curse. The Dunlavy’s need some support in the nether regions and a pair of HSU subs do add a solid foundation to music which enhances the overall presentation; however, it’s at the expense of some stage depth, width and image dimensionality. Placing the subs a few inches forward of the front plane of the speakers helps a little but that isn’t where they perform at their best as ‘subwoofers’.
Finding optimal room positions for bass augmentation always creates a clash with the phase aspect of integration resulting in the diminished soundstage described above.
Playing with phase settings has little impact on the problem since there’s just a toggle for 0 and 180.

Which brings me to the questions - 
1/ How does running a swarm setup, with 4 subs, affect phase/time integration with the mains? Does it create twice or half the issue or remove it altogether?

2/ Looking at subs such as the JL Audio F series with auto room calibration, does the EQ algorithm compensate for any time/phase anomaly or is it simply looking for a more linear bass response?

I don’t mind investing in more sophisticated subs so long as I don’t end up with the same problem. I’m not really inclined to mess with software and the like, unless there’s no other way.

Thanks

Rooze


128x128rooze

millercarbon2,336 posts12-29-2019 10:38amEQ is a lame idea, DSP or otherwise. But no more lame than taking advice from a bunch of guys with absolutely zero idea what they’re talking about. Which is every single post so far!
1/ How does running a swarm setup, with 4 subs, affect phase/time integration with the mains? Does it create twice or half the issue or remove it altogether?

It removes it altogether.
millercarbon, Which brands or types of DSP have you used to make such a sweeping generality?

I’ve used four properly placed self powered subwoofers and after adjusting their basic crossover and gain then saving those settings to memory, they did eliminate my rooms modes. Using one of the DSP calibration equipped subs as a master the room measurements clearly showed that time, phase, and frequency issues, in my room still needed to be addressed. Comparing the memory of the original non-EQd version to the EQd the improvement in the crossover region alone was quite dramatic.

I’m not doubting anybody’s feeling of success and satisfaction with their setup, better bass of any type can be a sea-change improvement in this hobby and I share in that enthusiasm. I also share in Eric’s suggestion of using competent DSP for the subwoofer region only. Depending on the room, any user may find one or two subs can substantially reduce their rooms modes and satisfy their low frequency tastes.

Four or more subwoofers in a room can eliminate a rooms modes and may seem like a panacea but its only one aspect of integrating extra low frequency with a system and the room.
Variable multi-band parametric equalization, filtering, Q settings etc., can make for a far more desirable level of crossover integration and personalization that the OP seems to be seeking.

I found the JL Audio F series very well made and very potent for their size. If I remember correctly the majority of their ARO/DARO equalization adjustments are Automatic Room Optimization only and may have led to their developing a manual solution with their companion CR-1. Comparing DSP procedures is very important.
I have a large room which requires large subs. I have had 2 SVS powered subs for around 10 years that I futilely attempted to integrate. The biggest issue is the carp adjustments on the power plates, starting with the volumes control that raise volume too high when barely turned up from zero. These at least have a sweep Phase which does allow for other than 0 or 180.


I never had the negative sound stage experiences you mention, but could never get them to blend seamlessly, but when the Polarity/phase was out (on numerous discs), reversing the bass Phase/polarity solved the problem, no matter which main speakers. I had Magnepan 3.5Rs, Usher 6371s, and Emerald Physics KCIIs. Most likely an expensive active XO is needed, but my system is all diff balanced, which makes active XO in the price range of new speakers


I am attempting to eliminate the integration problems by replacing the KC IIs 10" woofers and eliminating the subs with EP 2.8s as each speaker has 2 @ 15" carbon fiber woofers. should they ever show up. They ave a few pair of these $10K speakers available for 50% off including shipping
hth
Erik, what you dont seem to understand is i have ultra perfect high standards. I have heard many high end speakers, and they sound dreadful. How do you explain this? I see and hear problems that seem to elude experts like you. Why is that? Your speakers are nothing more than box speakers. They are equivalent to every other box speaker both in their strengths and weaknesses. The differences that do exist between your speakers and every other box speaker, are immaterial.
     The truth is that the 4-sub Distributed Bass Array (DBA) Concept actually works like a proverbial charm!  There are no ifs ands or buts, no maybes, no under the right conditions, no excuses, no fear and loathing, no terms, no conditions, no stipulations, no hidden clauses, no fine print, no oils and no qualifiers whatsoever.  
      It's the cat's pajamas, the bee's knees, good as gold, tits, right as rain and too legit to quit.  I believe it's the gold standard of sub systems that all others should be judged against.  
     Based on the 4-sub DBA's near state of the art bass quality, I actually continue to be amazed that it isn't more widely known, accepted and utilized, especially by fellow Audiogon members who are typically keenly aware and accepting of high quality audio related concepts, technology and methods they can utilize to increase the performance of their systems.  Heck, the main reasons we're all members is that we enjoy good music, realize high quality audio equipment, technology, concepts and methods are capable of increasing our systems performance and musical enjoyment as well as enjoying learning of, discussing and sharing this information, Right?
     The very relevant and utilitarian concept of the 4-sub DBA isn't exactly new, either.  I believe it's about ten years old and began as a spark of an idea that Duke Lejeune, owner of Audio Kinesis, had while having a conversation with his friend,Dr. Earl Geddes, about the results of the doctor's research and experiments on in-room bass performance in smaller room environments. Dr. Geddes stated that his research indicated to him that 4 well distributed subs in a room reliably provided the best in-room bass response performance regardless of the small room's dimensions or main speakers utilized.  This knowledge was the impetus for Duke creating his 4-sub Swarm DBA system that has won multiple product of the year awards (2015 and 2019):
2015:
 https://www.theabsolutesound.com/articles/audiokinesis-swarm-subwoofer-system/
2019:
https://www.theabsolutesound.com/articles/2019-golden-ear-awards-robert-e-greene/

     
      
       I've utilized an Audio Kinesis Debra/Swarm 4-sub distributed bass array (DBA) system for about 4 years now with a pair of Magnepan 2.7 QR main speakers.  I use my system both for 2-ch music and for 5.4 ch surround sound for HT.  I now use it with a pair of Magnepan 3.7i main speakers with equally excellent results, I just needed to adjust the volume and crossover frequency controls on the sub amp/control unit a bit.


Kenjit,
To paraphrase your post in another thread:
I refuse to engage with you unless you can prove to me it would be worth my time.