Posted by Wayne Parham [ 70.234.130.147 ] on January 14, 2007 at 12:43:03:

In Reply to: Re: Question about attenuating the 2123 posted by bill epstein on January 14, 2007 at 03:24:49:

Oooh, that's sweet, Bill. You have all the right stuff for a great speaker.

For your midrange driver, you don't want to use the attenuator configuration I use for compression tweeter padding. It is a special case where I want a specific load on the crossover that makes it underdamped. I do this to create a shelved region for a couple of octaves between the crossover frequency and the HF range where augmentation begins. So this kind of network allows some peaking to develop.

Instead, you want something closer to what I use on the midhorn in the seven π. Its job is to provide pure attenuation without allowing peaking or providing excessive damping. It provides a little bit of damping, but it is pretty much a matched load. I suggest the same thing would probably be good in your speaker.

Try this and see how it sounds for you: Assuming your midrange is an 8Ω 2123H, use an 8Ω resistor in shunt across the midrange driver and a 4Ω resistor in series before that. If it's a 16Ω 2123J, use a 16Ω shunt and 8Ω series resistor instead. For a crossover, try running it wide open and see how that sounds as a full range. You might add a coil to tame the top end a bit. Start off with values around 0.5mH for a 2123H or 1.0mH for a 2123J. I wouldn't use a capacitor, allowing the woofer and midrange to overlap. They're close enough they'll act as a single source at low midrange frequencies anyway because they'll be within 1/4λ of each other.

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