Your experience of moving to two subs

The argument that convinced me to go with two subwoofers says:

The bass wave is extremely long at the low end of the sub’s output, and the listener cannot tell where it originates.

The sub’s output higher up the spectrum enters the zone where the listener can tell where it originates.

And we want every directional cue we can get for the best soundscape.

Admittedly not much information is ‘lost’ to the listener with only one sub - if any is ’lost’ at all at those frequencies - you’re already down at 28Hz.

It’s a matter of a few percentage points improvement, maybe only 1% or 2%.

For me it was vital improvement.

Bass and drums took on a richer, finer texture, and the soundscape resolved more completely.

But then, my crossover points are in the low thirties and upwards of fifty for Magnepans.

@ditusa The article written by Doug Blackburn exudes confidence and it sounds plausible, but I disagree with a good portion of his assertions due to my experience. "Listen to a subwoofer all by itself for a while. You won’t hear anything vaguely resembling speed coming from that slow, soggy-sounding, plodding subwoofer. It has no detail and no speed whatsoever when heard all by itself."

I’ve done this with different subwoofers and they sound different. The SVS SB2000’s perceived quality of rapidity vs slowness changed significantly when changing its power cable with those of different materials and constructions. I started a discussion thread here about it some time ago.

The way I see it, the audio hobby is really about listening. Some people can detect differences just by listening, so they don’t rely on concepts so much, just like some people who can see clearly at very far distances don’t need corrective lenses. Some people don’t have the ear/brain training/gift/whatever to perceive as acutely, so they rely more on measurementation and abstraction. This is the primary basis for my system building, and the reason I disagree with the author.

I’ll give the other article a read today. I think it’s more up my alley.

I have 2 subs-10" Eminence.  We run these with a Yamaha power amp, commercial.  I have never ran out of power.  I have a Marchand  crossover to make sure the level is right for subs and mains.  The crossover is at 100 Hz.I don't have phase adjustment.  These subs are where they were for 20 years.  I don't know if it would sound better somewhere else.  Recently I removed the crossover and ran the speakers fill range. Not as clear, less bass and transients all were not as good.  Why?  The subs reduce load on main amp and reduce intermodulated distortion.  This causes the mids to be not as clear.  I  have 2 bass traps and 6 first reflection with 3 diffusion panels in rear.  I finally have the system so I can walk around the room and the sound is the same, except no imaging.  I could buy a couple more bass traps, don't cost much.

I've gone from 1 Rel to two Rythmiks and now adding 2 more Rythmiks.

Going from the Rel Storm III (vented) to two Rythmiks F12 (sealed, in heavy DIY box, aluminum cone) was definitely an improvement in every way. My audio setup is in the living room so ergonomics dictate plausible places for the sub/s - which aren't that many. So it's really no surprise that two worked better than one (and 2 servo-driven Rythmiks were cheaper than the Rel to boot).

Later I experimented with stereo vs mono subs (both subs playing the same signal) and didn't hear a "stereo" difference - I was crossing over at 60-70Hz. I used the Rythmik's xo for a while to relieve the main (tube) amp and speakers from reproducing low bass and that was definitely an improvement. I did get a measurement rig to correlate what I heard with what I measured and with what I read in papers/online/books.

Eventually I went with a fully active system and have the signal for the subs sent to a miniDSP 2x4HD and implemented MSO (Multi Sub Optimizer) and believe that was another improvement. With MSO you take measurements of each sub at each listening position you define and the software optimizes (amplitude, delay, PEQ) for the flattest response across the defined listening positions. So I used my two subs to simulate having 2, 3 or 4 subs at the different locations I could live with and ran the optimizations. That showed that 3 subs were better than 2, and 4 were better than 3. This is consistent with Earl Geddes' approach. He has said 3 subs would be enough, provided there is freedom to locate them, which I don't (all need to be on the floor, two visible by the main speakers and two under end tables). So I went ahead and purchased 2 additional F12 kits. I'm building the boxes now.

Still TBD if all this will be worth it, but it has been a fun learning journey 😀

I've just started playing with this in a PC system.  I'm buying small subs off ebay for cheap and now have 4.  2 tiny PSB sub series 100s and 2 Episode 8" Evo subs.  Episode is a custom install brand and has terrible resale value because nobody knows what they are.  I took a small chance for about $150 including shipping and it's definitely better than I'd expect for that price.  They're not blow the doors off HT subs but get you down to the high 30s.  All 4 subs are sealed.