Do you think you need a subwoofer?

Dear gregadd: That system is a " impressive " cost no object alternative.

However, those Gothan's are used as a bass re-inforce " tool " where the Alexandria's works full range.

Here, the owner's system choose ( IMHO with all respect I take this system example like that an example only and not like a critic on it and not telling that my " voice " is the only and right one. ) not taking advantage on the subs whole subject ( well he is taking advantage on the bass re-inforce but with many trade-offs, one of them is that the main speakers are playing in the low bass at the same time than the subs. ).

I f I was " there " ( unfortunately I did not, a healthy " envy ". ) my choice will be for the Velodyne's DD-15/18 or the DD-1812, both have a high-pass filter that we need to liberate the Alexandria for the low bass range.

The Velodyne choice not only give me that HPF but better specs on bass frequency range and its HD is the lowest on commercial home subs: less than 0.5%, this is very important because we want a clean in room response down there and according with the HD " quality " of the main speakers.

Other advantage to separate the low bass on the Alexandria's is that those Lamm's amplifiers will perform better with out " see " that bass range.

The Alexandria's are " easy " to handle almost for any amplifier SS/tube due to its very high efficiency ( 95db. ), Wilson say that you can start with amplifiers that put at least 7 watts but IMHO and due to its low impedance ( 3 ohms. ) and complex electrical impedance curve this speaker is not an " easy " one and its needs ( like the music needs specially on transients. ) are demanding to a matched amplifier ( not almost any. ) to show its best and great quality performance.

The sub's integration in true stereo fashion IMHO can help to improve the quality performance of the Alexandria/Lamm combo.
Of course that I can be wrong but this is what I think about and what I do with that system.

Gregadd, the audio/music home sound reproduction is a very complex one if we want to achieve a near " perfect " quality performance. The audio chain has many links and the relationship between those links are almost infinite.

IMHO each of those links has its own learning curve where we have to understand the differents steps in that learning curve to take its advantages and try to eliminate its dis-advantages. This link/chain " learning curve " know-how is one of the keys to our " audio dream " sound reproduction.

The sub's subject is one of those links where many of us are at the begin/start of the sub's learning curve, we need to grow-up ( like in other audio link's learning curves. ) learning with true experiences about, it is very difficult to learn if we don't " live "/feel with experiences on the subject.

IMHO as we grow-up on each audio link " learning curve " as better ( not only different but better. ) quality performance will show our home audio system.

Regards and enjoy the music.
Raul.

As usual Raul you are not without an good opinion. Dragging us kicking and screaming to better sound.

My point was just because you have a big expensive full range speaker does not mean you don't need subs.
As for what the crossover point should be and whether Jl or Velodyne is the proper sub I'll leave that fight between you and the Doc. I'm in enough controversy.
Gregadd

The sub's alternative IMHO is a tremendous " tool " to improve almost any home audio system quality performance that use tube amplifiers.

Due to tube technology characteristics and the fact that in a sub's system the amplifier does not " see " bass frequency range this improve the tube amplifier overall " power " in the remaining frequency range ( main speakers ) and permit that this un-stressed tube amplifier performs and match better to the main speakers.
The quality improvement is really significant and IMHO this " road " is a must to go specially when we are using tube amplifiers, I can't imagine a better system up-grade everything the same.

Regards and enjoy the music.
Raul.

Dear Gregadd: No fight, I respect that great system owner: it is only that maybe there is a tiny " room " to improve. Always is a temptation try to help, no critic at all.

Regards and enjoy the music.
Raul.

Raul:

I agree with your basic thesis about using stereo pairs of subwoofer for improved performance in virtually all sonic categories. I note that you are proposing using a high pass filter to prevent the bass drivers from handling the lower frequencies. In fact, you are suggesting this approach even for such stellar bass producers like the Wilson Alexandria. I prefer a slightly different approach: I would characterize it as “low bass augmentation”. In my system, I am running the Magnepan 3.5 full range. In my room the Maggies are down about 3dB at about 30Hz. I am running a stereo pair Sunfire Signature subwoofers with x-over point about 30 Hz. The slope and phase are adjusted to ear. I have been able to obtain seamless blending among the Maggies and the subwoofers.

I did not want to use the high-pass filter in the subwoofer because I felt that any gain in freeing up the Maggies from handling the bass frequencies would be offset by the added distortion or corruption of the signal due to the additional filtering. In fact, I experimented with both scenarios and preferred running the main speakers full range. The sound was less mechanical sounding.