What is a scientific way to integrate a subwoofer to the main speakers?

VoyR

Dear fellows,

The presence of subwoofers fascinate this old ass. Without the low frequencies underneath, the incompleteness empties my musical desire. If I had not known the difference with and without, I probably can live with it. Thanks to the Algame which reproduces bass with weight and speed.

As I mentioned earlier, I am about for a change. That is not to say my current speakers can't serve me well. I am aiming at the next level. Given Algame's amazing capability as a full range speaker, it is not easy for me to take a quick move.

The integration of subwoofers to the main speakers to me is quite problematic. Can anyone share how do you reconcile all the differences between amp gain and sensitivity of drivers to warrant a good integration?

In the case of Cessaro beta, even assuming sensitivity of the TAD drivers in the main towers is as the same as the 16", but the bass is driven by solid state amp with an unknown gain factor. The Tron 211 amp must have much lower damping factor and potentiall lower gain than the solid state amp driving the bass driver.

When I asked PT, he said the manufacturer adjusts by ears. Sorry Pal, I don't buy them because how can I trust anyone's ears? What I need is a detailed systematic way of solving all these inconsistencies. I am not buying someone else favor but my own.

VoyR

I hope my question can spark off some fires of intellectual discussion here. The Cessaro has its own magic. I listened to the Beta 0.5 and the full Beta system. What I can say is the room needs to be much larger to accommodate the bass horn. Although the bass horn produces too much energy, I can clearly feel the speed of all frequencies has become much faster. I asked PT to play at low volume, it is very good much better than 0.5 where the lower mid-bass is too slow with inadequate energy. The energy of the mid-range driver is too dominant.

But with the 0.5, PT can turn a much louder volume than the Beta because his room can still swallow the energy. But no doubt that the Beta is miles ahead of 0.5. I also notice the speaker position of 4 major monster varies tremendously. This PT guy said he dosen't really care about them as some strange plastic bag man helps me to find the right spot. Imaging is quite good but I still feel the integration is not up to par with what I experineced with the Tidal suite setup.

John

Voy R, I don't know if you'll ever find a 'scientific' way to integrate a subwoofer to the mains. However, hopefully there a few basic 'surefire' fundamentals that work most every time.

1) Assuming the subwoofer is active (self-amplified), then you should use the exact same interconnects for the sub that you use elsewhere in the system.

IMO, this is usually the most common oversight. Every interconnect induces time smear distortion (and other issues) to one degree or another. A very 'fast' sounding interconnect generally induces very little time smear and thereby give the impression that the tempo of a song is much faster than say an inferior interconnect. Using an inferior or different interconnect on the subwoofer will almost always give the impression that the subwoofer is disjointed and even disconnected from the mains, even if the sub and mains are made by the same manufacturer.

2) Location. Get the subwoofers as far away from the room corners as possible, even if the subwoofer manufacturer recommends the corners. Room corners heavily influence the performance of a sub (usually not for good) and will make the sub sound thick, boomy, overwhelming, woolly, and/or slow, almost like a dull rolling earthquake with little or no definition. Real bass is extremely tight and fast and well-defined, just like all the other registers across the frequency spectrum.

3) Ensure both mains and subwoofer are making the same solid contact with ground surfaces.

In my limited experience, this is my only hope of properly synchronizing a subwoofer to the main speakers while simultaneously creating the most realistic, tightest, deepest, most well-defined bass you may ever hear this side of live music. When you get the bass right, it's the most incredible experience.

Hope this helps,

-John

VoyR

John,

Thanks for your valuable input. How do you deal with the phase issue?

John

Voy R, for the record I've not used a subwoofer in 7 years but given the right circumstances I wouldn't hesitate to use one.

To your last question my understanding is that any given recording on a CD / LP can be recorded in-phase or out-of-phase and it's not much better than a crap-shoot.

My experience further leads me to think that perhaps only a simple majority of recordings are recorded in-phase and for that reason alone I've always had the greatest satisfaction when setting the subwoofer phase to zero worked best overall because I prefer to set and forget and I'll suffer just a little through the tracks recorded out-of-phase.

By the way, I apologize if my first post seemed overly simplified. I'm well aware that with high-end audio, as perhaps with high-end anything, ultimate success requires properly addressing a number of aspects from a more holistic system perspective. But when dealing just from a newly purchased subwoofer integration perspective, those 3 things I listed below are the first items I attempt to address and resolve.

-John

Lee

Hi Voy,

Speaking as someone who has integrated subs in 2 different systems (including several moves to different apartments over the years), i have some experience in this. I currently use a Velodyne DD-18 which i run in parallel to my Wilson X-1/Grand Slamms. (In parallel, meaning the Wilsons are running full range, and the Velodyne i have set to run up to a maximum of 35 hz).

The great thing about the Velodyne is there are at least 20 computer driven adjustments you can make (multiple frequencies, phase angle, cutoff, hi-pass/lo-pass, etc). And the Velodyne comes with a microphone and feedback system that can get you started by automatically adjusting the frequency as picked up by the mike to make the frequency response of the Velodyne flat within your room.

i personally find that i let the Velodyne automatically adjust to a flat response...and then i typically adjust by ear from there...to adjust for my personal tastes but also for the fact that the human ear apparently could use a slight boost in bass (sometimes as much as 6db) given our differing sensitivity to bass vs treble.

Velodyne is one of the best out there...but not the only one that comes with this kind of built-in adjustment capability/flexibility.