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In the Forum: Horn-Loaded Speakers
In the Thread: Cogent+Electronluv+Acapella=Wretched What?
Post Subject: The Cogent architectural problem or the Cogent++Posted by Romy the Cat on: 9/5/2007

I do not know the characteristics of the Cogent bass driver. I do not like the entire idea of a bass driver be electromagnetic as bass defeat itself first with field coils, still if electromagnets is something that Cogent intend to do then they are within their “constitutional rights” to do whatever they wish. What however is very obvious is that Cogent’s desperate need for one extra channel. Let me to explain.

Let presume that the Cogent bass driver can handles 40Hz. Why not? The horn loading of 40Hz requires a near 6-feet (2M) mouth. You can not go away from it. The “other” (MF+HF) channels might be positioned above, below or on the side of that large 6-feet mouth. If Cogent put it above, in time aligned position, then “bye-bye imaging” (Picture “A”). Putting them on the side is controversial as it requires a VERY sharp low-pass filter on the big horn. It is posable to put the MF at the bottom of the big horn (bringing the horn up) but the MF must be at near ears level and it will leave a large empty space under the MF driver, not to mention that now the weigh of the sound is radiated from “above”. Now look: we have a “large empty space on floor” and we have the “top prevalent” imaging… How it might be resolved? The only logical solution is introducing contra-balance channel that would be located under the MF channel. (Picture “B”).

Cogent++.JPG

However, here we hit another subject: if the “floor channels” has own bandwidth then this bandwidth not needed in other drivers… So, the selection of the drivers, horns and the way in which they might be use very different. It is possible that Cogent might use 2 of their MF driver in their newCogent++ configuration: one on 200Hz horns and one on 900Hz horn. How good would be those driver for the more narrow bandwidth – only god knows… What I know defiantly that in 2-way installation (aka RCA movie configuration) the Cogent will always be condemned to sound like…. a movie from 30s… Rgs, Romy the Cat

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