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The Impresario Browse Projects - Submit Project


- Enclosure Design -

The Impresario has a sealed enclosure. It's modeled, having a similar volume as the Dayton III. Front baffle measures 9.0"w x 29.5"h including the 2" radius curve on top and bottom. Construction of the top/bottom caps requires a more advance skill level and without doubt will be challenging to some DIY'ers.

A more traditional loudspeaker baffle (rectangular enclosure) for this design would measure 9.0"w x 27..5"h. If you're going to use vinyl veneer round-over vertical corners of baffle. Construction of this enclosure is quite easy and should take less than a day to cut and assemble the cabinets and baffles.

The 295-306 woofer enclosures have an adjusted volume (w/drivers installed) of about 430 cu in each enclosure. The Qtc at 0.65 is about 415 cu. in., F3 of 71 hz. and Driver Resonance of 65 hz. Polyfil is sparingly stuffed within center of enclosure. Drivers are sealed with a 1/8" thin foam sheet type material used as shipping packing, simply traced and cut to size with scissors.

The 275-075 tweeter resides with upper woofer. Its volume calculated into the adjusted volume of enclosure. The 295-301 mid woofer enclosure has an adjusted volume (w/driver installed) of about 440 cu in. The Qtc at 0.65 is about 450 cu. in., F3 of 77 hz. and Driver Resonance of 70 hz. Polyfil is sparingly stuffed within center of enclosure. Drivers are sealed with a 1/8" thin foam sheet type material used as shipping packing, simply traced and cut to size with scissors.

Curt C. suggested extending the mid enclosure back to the rear wall and making it narrower by mounting the tweeter in the upper woofer enclosure. It would have separated the two woofers into chambers of unequal volume but not if the mid enclosure is angled upwards from front to back to compensate. This required an 11.0" separating wall at 30 degree bevel.

Standing waves: In the Impresario design the fundamental standing wave will be at roughly 250 Hz. Standing waves can result in colored boomy or heavy sounding vocals. Dividing the enclosure into separate angled woofer sections will push the resonant frequencies upward into the stop band of the woofer, precluding their occurrence.

Enclosure integrity: The mid enclosure panels now tie the four sides of the enclosure together with asymmetric shapes, spreading out the remaining panel resonance over varying frequencies. As for the offset, mid woofer sound surface wave would not hit back wall except after hitting offset angled panel first. This and the narrow baffle will likely eliminate the need for the double thick front baffle, although it won't hurt to still do it.

Midrange improvement: The actual mid enclosure volume is not critical as long as it adequately sized to absorb the rear pressure wave. To this end the longer enclosure will be advantageous over one where the back wall is only a few inches away. A minimal amount of stuffing will be needed to absorb the pressure wave reflected off the back wall.
Impresario Enclosure Drawing

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Impresario-Triune Enclosure Drawing

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Impresario Lower Endcap Drawing

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Impresario Upper Endcap Drawing

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Impresario-Triune Endcap Drawing

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