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ayebee wrote:

I’m probably suggesting the obvious, but have you tried adjusting the crossover component values on the fundamentals and MF-channels? On the fundamentals-channel, increasing the inductor-value, and decreasing the cap, so that the slopes cross on the same frequency, but in a lower amplitude, could be one way to decrease the sensitivity without resorting to resistive attenuators. The same could *perhaps* be applied on the MF-channel as well. When I changed the driver in my upper-bass horn, I could increase the cap on my JBL 2420 MF-driver from 3 (if I remember correctly) to 3.3 uF to match the increased sensitivity. This change actually affected sensitivity of the MF-channel more than it did affect tonality. Of course, this is just another way to burn sensitivity, so that particular headache is still not cured. Could you perhaps post a schematic of your current crossover?

Anders, yes and no. You need to be careful playing those games. First of all adjusting the sensitive via crossover works only what the driver sit on transition slope. It means that driver does not operate in a horizontal section of response.  Let take foe instance your JBL 2420. It you use it from let say 7kHz and up with first order then you might to a degree adjust the sensitivity of the channel by moving it higher or lower on the slop. However, if you have your JBL 2420 sitting at 1000Hz or 500Hz then you have no such option as you need your driver to demonstrate linear sensitivity from 500hz to 12KHz.

The adjustment sensitivity by crossover would work on tweeter or on the bass channels if they do not work very wide. It would work technically very well on the Fundamentals Channel if it has a very narrow bandwidth, however, I would not advise to use the crossovering method for Fundamentals Channel. You see, the Fundamentals Channel sets the scale of the MF weigh. It is hard to explain you need to play with it - when you add and reduce the Fundamentals Channel’s output then you moderate the body size the instruments resonators, you can set their perceptual speed and their “seriousness”, you can moderate the level of musical legato of enter presentation and you can tight the upper channels with bass channels to a very high level of “accuracy”. I use “accuracy” in quotes as it is not the “accuracy” per say but rather your perception of “how it shall be”. There is a kink in it though. When you are setting up your Fundamentals Channel via non-inductive volume controls then you change only the Channel’s output. However, if you do not use volume controls but move the channel up and down on the transition slope via crossover then with each change of filter you introduce new phase characteristics and you need to do time re-alignment at each new volume level. The bitch is that when you re-align time then you get new amplitude. You then kill another .5dB of amplitude and then you need to re-align time…It might be a bit pain in ass to do.

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