Hi Sean,
To respond to your main points:
1. It is a mistake to make a blanket assumption that increased excursion per se is a serious problem, provided that the linear limits are not exceeded. While in an ideal world, excursion would be kept to zero, that obviously would require a driver with infinite surface area. The point I tried very hard to make in my post, and which was apparently lost, is that there are many, many other issues in loudspeaker design, all of which are extremely important. While it would certainly be nice to minimize excursion, that automatically requires doing others things that, in the final result, are far more detrimental to the overall performance of the speaker. I will repeat: the recent development of highly linear motor systems has not eliminated, but HAS substantially mitigated the problems caused by high driver excursion. The proof is in the listening.
2. Regarding power handling, you did not read what I wrote about the BOMB very carefully. I pointed out that while there is a 10dB boost at the amplifier, there is also nearly a 10dB loss in maximum output at the speaker. It is actually somewhat less than this, but the implication is that in the final analysis, the speaker does not receive significantly more power with the BOMB than it could take without it. In fact, on a lot of music, the argument could be made that the average power delivered to the speaker is actually more limited with the BOMB in place, due to the linear excursion limits of the drivers. In addition, thermal compression effects are far more important on an instantaneous basis than on a long-term one. In other words, when one is speaking of thermal dynamic compression, it is not a significant issue to dissipate heat from the driver chassis into the outside world. Certainly the aluminum baffle helps in this regard, but the primary concern here is with effects that are measured in nanoseconds, which the baffle doesn't help in the slightest.
3. Again, as I tried very hard to point out in my original post, it is useless to discuss "deep" and "loud" without having defined those terms, because it varies so much from one listener to the next. The UM/BOMB system, properly set up in an "average" room of, say, 4000 cubic feet, will be able to achieve an average continuous SPL of 90dB on typical rock/pop/jazz/folk recordings, extending flat to about 30Hz and being 3dB down at about 25Hz, without audible strain. Now, I will make the assertion that very few people who value their hearing will ever exceed this level. It is MUCH louder than most sane individuals ever listen. However, audiophilia is a diverse crowd, and there are certainly exceptions. Again, as I pointed out in my original post, that is why the UM is designed to integrate so well with high-quality subs such as the RELs. The combination of a pair of UM's and Stentor III's, when properly integrated, is something to behold.
To Eldartford:
If you have read our website, it is clearly stated that the Linkwitz Transform was developed over twenty years ago by Dr. Siegfried Linkwitz. And I am eternally grateful to him for having published it, for it is by far the most elegant solution I have ever seen to this particular problem. The BOMB is most emphatically NOT a "band-aid", as you seem to imply, and has nothing to do whatsoever with having chosen "too small a box" (it is, in fact, exactly the right size), but rather is an integral part of achieving a level of performance that is well outside of the experience of most audiophiles.
Secondly, your statement about the ease with which the baffle can be made on a CNC machine betrays a complete ignorance about manufacturing techniques and production costs. As someone who has over a decade of experience with state-of-the-art CNC production machining and several decades of experience in advanced composite construction, I can tell you categorically that you have no idea whatsoever what you are talking about. If I had any sense at all when it came to minimizing cost (and making a profit), I never would have chosen this manufacturing approach. I would have banged out the enclosure from CNC-routed MDF or Corian or phenolic laminates, or laminated it from pieces of solid wood, or at the very least made it from extrusions and flat slabs of aluminum ala Krell, which would have been 1/10 the effort and cost (this is not an exaggeration, believe me). But this speaker was never meant to be a "me too" design. It was intended as an all-out assault on the state of the art, and its success is in large part due to the extraordinary effort put into the cabinet.
To Metralla:
Thanks so much for the kind words. It was indeed an honor to have Stan Ricker in the room, and a delight to hear his comments. One of the highlights of CES for me, to be sure.
Karl Schuemann
AudioMachina
