Performance Optimized Down Fire Sealed 10" Enclosure | Hertz Mille Pro MP 250 Single 10" Sealed enclosure

Two reasons, both driver geometry. The MP 250 mounts 5.80 inches deep, and it displaces 3.2 liters of airspace on its own, which is substantial for a 10 inch driver. Our double baffle recovers 0.75 inches since the outer layer is a flush recess and the driver bolts to the inner layer, and a 3/8 inch milled relief behind the magnet recovers a little more. Even so, the minimum internal height works out to 5.1875 inches, which is 1.00 cubic foot net after the driver's own displacement.

The result works in your favor. At Hertz's 0.60 cubic feet the system sits at Qtc 0.849 with F3 at 40.6 Hz. At 1.00 cubic feet it lands at Qtc 0.741 with F3 at 39.4 Hz. Better damped, tighter transient control, and marginally deeper extension.

Depth and excursion. The MPS 250 is the shallow-mount version at roughly 4 inches deep, and its Down Fire enclosure stands 4.9375 inches tall. The MP 250 mounts 5.80 inches and needs the 7.4375 inch cabinet on this page.

In exchange the MP 250 offers more excursion at 17mm linear against the MPS 250's figure, more power handling at 600 watts RMS, and a lower free-air resonance. If vertical clearance is your constraint, the MPS is the answer. If you have the height, the MP is the more capable driver.

It is Hertz's cone geometry, shaped so the diaphragm resists bending rather than relying purely on material thickness. The cone itself is made by pressing paper pulp with mineral powders injected into it, the same construction technique Hertz uses on their flagship Mille Legend line.

The point is that the cone moves as a rigid piston instead of flexing at the outer edge as excursion increases. Cone flex is a real source of distortion at high output, and it is one of the things that separates a well-engineered driver from a cheap one at the same nominal specification.

The enclosure has one side-mounted Proline X terminal cup pre-wired in 12 gauge OFC. Final impedance is set at the driver, and it depends on which version you buy.

The MP 250 D2.3 has dual 2-ohm coils: parallel gives 1 ohm, series gives 4 ohms. The MP 250 D4.3 has dual 4-ohm coils: parallel gives 2 ohms, series gives 8. Hertz rates the driver at 600 watts RMS. Confirm your amplifier is stable at your chosen load before powering the system.

Side mounted. Every Proline X Performance Optimized enclosure uses a side mounted terminal cup regardless of alignment, whether standard, wedge, or down fire. On this cabinet that keeps the connection fully accessible with the enclosure in its installed position, since the baffle faces the floor. The cup is our Proline X ABS and carbon fiber composite unit, recessed, with stainless hardware, copper ring terminals, and pre-wired 12 gauge OFC.

Down Fire cabinets are built with square corners as a series standard. The 3 inch top down corner radius used on other Proline X alignments does not apply here. A down fire box is a low, wide platform that sits flat against a floor or cargo deck, and square corners maximize usable internal volume for a given footprint while keeping the cabinet stable on its mounting surface.

V-groove and dado joinery, CNC-cut on ShopSabre routers from Langboard Elite MDF. Every panel joint is a machined interlocking groove that mechanically locks the panels before adhesive is applied, which is what keeps the cabinet airtight under sustained pressure cycling.

The front baffle is a double layer at 1.5 inches, two bonded 3/4 inch sheets, with the outer layer machined as a flush recess so the driver bolts to the inner layer. That recovers 3/4 inch of internal clearance for a deep driver. A 3/8 inch relief is milled into the opposite panel behind the magnet. Perimeter cross-bracing and pre-installed polyfill complete the build. Assembled and inspected in Tullahoma, Tennessee.

No. This listing is for the enclosure only. Bring your own Hertz Mille Pro MP 250 D2.3 or MP 250 D4.3. The cutout, mounting depth and magnet clearance are all cut specifically for this driver.