Your sub experience: Easy or hard?

nice article and very correct. A sub not only has to match the mains in frequency response but also in time. This is the problem with DBA's. They do a great job of evening out the bass response throughout the room. But, they are not necessarily and probably not matched in time with the main speakers. You have to be in phase and in time with the main speakers or you have essentially an echo. Bass transients like bass drums lose their impact. The buzz in bass strings disappears.

@mijostyn This is mostly incorrect unless you let the subs run up too high. At lower frequencies the 'time alignment' thing isn't an issue simply due to the length of the waveform. At 80Hz its 14 feet long and that means in most rooms its bounced off the wall behind you before the you can even know what the bass note even is (it takes a few iterations of the note before the ear can identify the frequency). By the time you've identified the note, the bass in the room is entirely 100% reverberant- there's no time thing. So yes: ALL bass in regular size room below probably about 80Hz is an 'echo'.

FWIW this is the case whether you have a single sub or a DBA or anywhere in between.

I play string bass; have since I was in 6th grade. The 'buzz' in bass strings comes from harmonics of the instrument, not its fundamentals; the former are handled by the main speakers.

A DBA has no adverse effect on bass impact (if you have a standing wave at the listening position it can certainly improve it); at any rate regardless of the subs you have if they (or it) allow proper bass at the listening position then the bass will be the same in either event regardless of single or multiple subs.

@erik_squires Yeah, it ain't easy maintaining order in the unruly cyber universe...😅

@atmasphere I absolutely agree, if you are crossing over at 40 Hz. If you are trying to "unload" the main speakers from having to make bass which is particularly important for speakers with smaller woofers, full range drivers and ESLs you have to cross up around 100 Hz . For over a decade I was crossing at 120. The wavelength at 100 Hz is about 10 feet depending on your altitude. Worse even if you are using a steep slope there can be useful output up to 200 Hz. These wavelengths fit into all residential rooms except closets. A lot of the detail in bass and slam comes from this range. I can show you in an instant playing a repetitive bass drum kick switching the delays on and off. I do have a special situation as I designed the house and this room was purpose designed to be a media room. All the speakers and subs form linear arrays and are very directive. There is very little room interference. I essentially have no back wall. It is all broken up opening into other rooms and hallways. 

Hoping to order my MA2s in a month or so. I'd say we are 95% of the way there.

Mike

@atmasphere , I forgot to mention we are talking about two different buzzes. I mean the vibration you feel as if you feel the string moving. The buzz you are talking about is the icing on the cake. It comes I think from the string vibrating against the fret board. I love listening to Dave Holland as he makes a lot of that noise playing. I just saw Marcus Miller and Mike Stern at the Blue Note in NYC and I was about 15 feet away from Marcus, best electric bass I ever heard. Now I have a new target to shoot for. I wonder why humans love having their insides rattled.

I have just this week been looking at some changes to my sub situation. My main speakers with two 9-inch drivers each in a very inert acoustic suspension cabinet perform very well with bass down to around 40Hz. I have been very happy with the sound resulting from rolling in two subs and cutting them off at around 40 Hz.

In discussions with the manufacturer of my speakers, he believes what I am doing is fine, but that I could gain improvements with a high pass filter set for 45 Hz, which could reduce doppler distortions resulting from the woofers reproducing lower midrange frequencies up to 360 Hz while at the same time trying to reproduce very low frequencies in the 30-45 Hz range. Marchand is in the process of building a passive balanced HP filter for me.

It is also my speaker/sub manufacturer's experience that two subs run in stereo (which is how I use mine) are superior to one mono, or running two in mono. He believes we can localize stereo sounds in the low bass to some extent making it worthwhile to run the subs in stereo. Regarding more than two subs, it is his experience that adding a third sub run in mono and located in the back of the room can provide significant improvements in bass, while going from three to four subs is much less of an improvement. He recommends adjusting phase using a trial and error method from the listening position. I have been planning to add a third sub but haven’t yet found one of the SW-12s that I use anywhere close to where I am located.