Are the JL Fathom subs really that good....

Irv, you may have hit on something. I am less than 12' from my speakers due to my smaller room so there is less chance for the sound to blend before I hear it. I wouldn't call my setup nearfield but it isn't "farfield" either. I thought that when I went to full range floorstanders the subs might be too much in the room but that is not the case with the proper (to my ears) adjustments.

Interesting. Since your post, Bizango1, I've more carefully listened to see if I could tell where the subwoofer is in my room. I have to admit the results inconclusive, for two reasons. First, my sub is positioned about midway between my main speakers (though not exactly midway), making the sub more likely to appear blended. Second, a lot of recordings are mixed with mono bass. Perhaps most recordings. This, of course, means that a centrally placed sub will blend even better. So it possible that the only reason I can't tell where my sub sits is because that's how the bass would sound even if the sub weren't present.

Irv, I have a large aquarium in between my speakers so I have never been able to locate the sub near the middle. Who knows, if I had I might never have been driven to try stereo subs. I guess the plot thickens as our system details come out. In my setup with the tank in the middle two subs to my ears are conclusively better. I suppose the bass blend across the soundstage could be inhibited by the half-ton body of water in the middle!

Jb8312
To be honest, I cannot "fathom" a sub integrating into 2 channel so well it is seamless, completely cohesive and disappears into the music…

It can be done, but it is very difficult. IME, seamless integration is only achieved when BOTH frequency response AND transient response are optimized. The problem is that it is very difficult to optimize both, and optimizing only one results in an audible "disconnect" between the sub(s) and the mains. To quote myself from another thread...

Much of the time and effort that goes into subwoofer setup is spent optimizing frequency response. That is typically done in one of two non-mutually-exclusive ways: Sub placement or digital EQ. Either of these approaches can result in a much flatter frequency response, making the bass sound less bloated. But both of these approaches can result in a sub-optimal transient response, due to the time misalignment between the sub and the mains. That makes the bass sound slow. To elaborate…

If placement is used to optimize the sub’s frequency response, then the sub often winds up closer to or farther from the listener than the mains, thereby misaligning the sub relative to the mains. Alternatively, if digital EQ is used to optimize the sub’s frequency response, then a processing latency is introduced into the sub’s the signal path, but not into the main’s signal path, thereby misaligning the sub relative to the mains. Hence either approach to optimizing frequency response can disturb the system's transient response, making the bass sound slow (or “out of sync”). On the other hand…

If you set out to optimize transient response, you will usually place the subs on a plane very close to that of the mains. Now the bass no longer sounds slow. But, due to room modes, this kind of placement often results in a highly uneven frequency response. Now the bass sounds bloated again...and so on.

The result of all this is that, when trying to optimize both frequency response and transient response, you often have the experience of chasing your tail. That is what I mean when I say that, under many circumstances, optimizing frequency response and optimizing transient response is a zero sum game.

IMO, the way to defeat the zero sum nature of this game is to:

1. Place the sub(s) to get the best frequency response (varies from room to room) and fix transient response problems with DELAY. This assumes you can independently delay the sub(s) and the mains, which doesn't seem to be a common capability in audiophile systems.

-OR-

2. Place the sub(s) to get the best transient response (i.e. roughly coplanar with the mains) and fix frequency response problems with EQ. But to the extent that the EQ introduces processing latency, you will have to move the sub(s) CLOSER to the listener than the mains. Again, this doesn't seem to be a common arrangement in audiophile systems.

-OR-

3. In light of (1) and (2), the most effective way to optimize both frequency response and transient response is to be able to INDEPENDENTLY CONTROL BOTH THE EQ AND THE DELAY OF BOTH THE SUB(S) AND THE MAINS. That allows you to correct for room modes (better frequency response) and time align the various speakers (better transient response). Very few systems have this capability, and for this reason, very few systems seamlessly integrate subs.

You said don't hold back.

Bryon

P.S. I use a Fathom F113 for 2 channel.