What process did you use to integrate multiple subwoofers for 2 channel listening?

@tvad, thanks for the thumbs-up! Not that this will ever be a question on Audiophile Jeopardy, but the the first generation Swarm came out way back in 2006.

@mapman wrote: “One other thing. I know audiokinesis is big on speaker dispersion patterns and how that affects the sound.”

Ha! Yes I do think in terms of radiation patterns quite a bit. From a psychoacoustics standpoint the room interaction situation is very different for different parts of the spectrum. Our brains have time to process the direct sound separately from the reflections at shorter wavelengths, but not down in the bass region, so I use different approaches to room interaction - i.e. different radiation patterns - in different frequency regions, the details being beyond the scope of this thread.

@hilde45 wrote: “The problem I’m not able to solve, and perhaps the room’s physics make it impossible, is a +5db or more bass hump from about 73-92 Hz."

Is this bass bumpage present throughout the room, or is it mainly present in your normal listening area?

Approximately where is the crossover frequency between your subs and main speakers?

What controls do you have on your subs?

How much freedom do you have when it comes to the locations of speakers and listeners in your room?

Thanks,

Duke

Jim Smith's Get Better Sound book has a good chapter on setting subwoofers for stereo music reproduction. He mentions some things I haven't seen mentioned in this thread.

https://www.getbettersound.com/

@audiokinesis Thank you for your questions. A few answers:

* I do not know if the bass bumpage is throughout the room. After a LOT of work yesterday, I got it down to about a pretty narrow peak which is +4db between 79hz and 93 hz with a +6.5db peak at 88 or so. In exchange for all my work knocking down a pretty big peak between 50hz and 80 hz, I wound up with continued/more nulls at 33.5 (-6.5db), 127 (-8db), 208 (-11db), 244 (-11db). These are now my major problems to figure out without retarding the bass progress I made.

* My front ported Salk SS 6M speakers are listed as rolling off at 35hz.

* These Rythmik F12SE subs have a wide range of controls, including variable phase, crossover, gain, low pass switch (50hz/24 vs. AVR12/80hz/24), a "Rumble filter,", Extension filtering switches for Frequence (14, 20, 28hz) and Damping (low, mid, hi). Details about these switches are here: https://www.rythmikaudio.com/download/PEQ3_sealed_quickguide.pdf

* I have a lot of freedom in this room. I did extensive listening, measuring, moving of speakers, etc. in the room and I think LP and Speakers are close to optimized but I’m open to revisiting.

Again, thank you for the questions. I feel like I made progress yesterday - I moved everything, turned and changed dials and knobs, moved treatments around, the works. I was systematic and cautious, changing one thing at a time. I listened at the end of the day and it sounded very satisfying. It’s now those big nulls which are leftover problems I feel compelled to solve.

Any suggestions you make will be experimented with ASAP. I'm a dog on a hunt.

@hilde45

Can you replace your old graph with a new one, and include measurements for the mains only. I think you'll find those nulls (127Hz, 208Hz, 244Hz) will remain unchanged with or without subs. This is where DSP might be of help to you if you're looking for perfection.

Fun stuff.