Sogood51: I liked your post. The comment about ports adding quantity but lacking quality is right on the money. The analogy of a smaller woofers vs bigger woofers and the boy / man comparison was also quite good.
Drew: very nice posts that are based on both common sense and science. Those two factors rarely meet when it comes to audio and audio forums. I applaud the efforts that you put forth in your post.
Michael: Drew never said that other speakers weren't deficient in providing usable spec's. I'm quite certain that he feels that most manufacturers don't provide anywhere near the amount of info that they should about their products, especially speakers. He just said that this speaker lacked the spec's that one really needs to properly judge a speaker on paper.
Given the claims being made for this speaker and the amount of technology that supposedly went into it, one would think that the manufacturer would want to "testify" to the actual performance of the product as much as possible. Your level of involvement / personal emotions seem to be clouding your response on this one. Then again, that seems to be a common situation when it comes to products that you endorse.
Karls: I want to highlight two of your statements. Here's the first one: "It still can't break the laws of physics, but if used within its linear excursion limits, will give extraordinary performance regardless of volume level or frequency".
The only way to maintain "extraordinary performance" with this speaker contradicts the "regardless of volume level or frequency" part of that sentence. That's because as either frequency is reduced or volume is increased, excursion also escalates. As such, what you've said is that "this speaker kicks ass / remains quite linear so long as the volume is kept to a reasonable level and one doesn't expect the deepest bass". As a few posts have pointed out above, you can't maintain high spl's and / or deep bass extension with lower levels of distortion without resorting to larger drivers.
Here's the other statement that i think requires further commentary / clarification: "The issue of the extra power required by the BOMB is more of a problem for the amplifier than for the speaker. The reason for this is that there is surprisingly little energy (on a continuous basis) in the deep bass. But when it appears, it can make very heavy transient demands on the power amplifier. The BOMB has a maximum boost of 10dB at 24Hz, which equals a factor of 10 in amplifier power".
The added power requirement of the amp is most definitely a problem that the speaker shares too. That is, the 10 dB increase in power that the amp must generate has to be dissipated. ALL of that dissipation takes place within the speaker itself. I think that this is why Drew mentioned thermal compression and power handling coming into play more rapidly with this approach than when using a larger driver with less requirement for EQ.
As a side note and to somewhat respond to Drew's comments, my thoughts are that the effects of thermal compression would be somewhat reduced with this design. This is due to the design of the driver itself and the fact that it will make use of the 2" thick metal baffle acting as a heatsink for the basket of the driver. While it is true that the voice coil & coil former are doing most of the dissipation in a driver, the basket and magnet structure also enter into the picture in this area. Given that the basket is mounted to a metal structure that should be quite excellent at dispersing heat, it probably has a sizeable advantage over other designs.
Other than that, this looks to be a very well designed speaker. I remember looking at it previously and thought it was pretty nice, but also way too costly. I do understand that there is a LOT of custom machining taking place here, but $10K for a "little" speaker is still a LOT of money. Then again, $10K for a "big" speaker is still a LOT of money in my book. I do applaud your efforts and appreciate the fact that you didn't try to push some type of bass reflex design on the public in the name of "more is better" bass response.
Bluebull: Actually, if properly done, relieving the midrange driver of the longer excursions necessary for low frequency reproduction, midrange response should be improved. Given that many two ways are a compromised design, it stands to reason that the same engineers would be even more confused when adding another driver, two more crossover points and a lot more parts to the equation. Sean
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