Your sub experience: Easy or hard?

@phusis  I though I was going to get a Trinnov Amethyst until this came along. The Trinnov's bass management is too basic and does not give the kind of flexibility I am use to. I have asked for the DEQX Pre8 manual so I can get an idea how it is programmed and will choose once I see it. If DEQX continues to organize things as they have in past units, the new ones will be fine. In trying to make the situation as simple as possible, some companies are making it impossible to fine tune a system. The other problem with the Trinnov is that it does not have a USB audio input. The DEQX has one.

@phusis , Right, all the cross overs you'll ever need right in your preamp. Fully programmable, nothing between the amp and the driver. 

@phusis , you must have a huge listening room. check out the DEQX web site. They are just now releasing a new set of gear and it is really serious stuff. You get either a Pre4 or a Pre8 and you will be in hog heaven!

@atmasphere , WOW, that is high up but not unusual for efficient speakers. They probably need the radiating area to keep up with the horns. Between 200 and 500 Hz is a big chunk of very important midrange. Relieving those 15" drivers of 80 - 100 Hz down would clean up your midrange quite a bit. When you play the system as loud as you are comfortable with, something with a decent bass line and a bass drum, can you see the excursions? If you cannot see it doppler distortion is probably not audible. If you can see it , it probably is. The kicker here is my experience is with full range ESLs. Do the same criteria apply to cone drivers. I do not see why not. The driver with the smaller surface area has to take a longer excursion.  

@atmasphere , you put your listening position in a null spot! You evened out the amplitude response in the room. It would be interesting to measure the group delays of the system before and after you added the additional subs. At what frequency do your 15" woofers cross to the midrange horn?

@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.

@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

@jrpnde , 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. The only way you can do this easily is with digital signal processing. The Anthem system was mentioned above. MiniDSP makes the least expensive unit that I know of. There is Trinnov, DEQX and Lyngdorf. People who are digiphobes need not apply and more than likely would be better off without subwoofers. You can not recreate a live performance without subwoofers. To do it right takes much more driver surface area than you would think. Residential rooms stifle bass. Add a processor to this and you have considerable expense. If you can not do it right you are more than likely better off from a sonic perspective not to do it at all. You can kiss the live performance goodbye but this is not what most people want anyway. They want a more polite system that is very detailed. They rarely listen over 85 dB and bass loses it's energy at this volume subwoofers or no. 

Another important aspect of subs is that they take the load off the main speakers which can make serious improvements with their performance in terms of distortion and headroom. Good subs do not low pass at 40 Hz. They are used in conjunction with a high pass filter on the mains and cross between 80 and 120 Hz then time corrected usually by delaying the signal getting to the main speaker so the group delays match at the listening position. You have no idea what is happening unless you measure it. If you think you can do it by ear, good luck to you. Getting it right would be like winning the lottery. Like everything else in this life there are no cheap easy solutions only people who want to sell cheap easy solutions. 

Sorry for preaching.