Hertz Audio Mille Pro MPS 300 S4 High Power Shallow Mount Car Subwoofer Review

Not all vehicles have a lot of space for a subwoofer, and my 2017 Nissan Titan King Cab is a perfect example. This is why shallow mount subwoofers were invented: to get bass out of tight spaces. But early iterations left much to be desired. Thanks to advancement in technology, they can now provide excursion, power handling and output similar to a standard subwoofer. Yet it’s still not common.  While it’s not common for shallow mount subwoofers to have this massive performance, they are available from a limited number of manufacturers. One of those few manufacturers is Hertz Audio.  Their Hertz Audio Mille Pro MPS 300 S4 is their top-of-the-line shallow mount subwoofer.  MSRP is $550.

 

Features and specs:

Size mm (in.)      300 (12)

Power Handling - Continuous W 500

Power Handling - Peak W             1000

Impedance Ohm             4

Depth mm (in.) 88 (3.46)

Voice Coil Type  single

No Filter Component     Subwoofers

Voice Coil Ø       38 (1.5)

Frequency Response Hz 25 - 400

Magnet size D x d x h mm (in.)    156 x 60 x 36 (6.14 x 2.36 x 1.42)

Weight of one component kg (lb.)            6.64 (14.64)

Magnet High density flux ferrite

Cone     Polypropylene

Xmech mm (in.) 20 (0.79)

Technical Specs

D mm    262.59

Xmax mm           16.80

Re Ohm 3,4

Fs Hz     23

Le mH   3,75

Vas I      62,13

Mms g  320

Cms mm/N         0.15

BL T*m 18.7

Qts        0.42

Qes       0.45

Qms      6.3

Spl dB   85

 

The Hertz Audio came in a color printed box with photos of the subwoofer and its specs. Opening the box revealed a well-protected subwoofer held in place with custom cardboard. Materials used in the construction was aluminum for the cast basket, copper voice coil, cloth spider, polypropylene woofer, and rubber surround. Quality of materials used, as well as fit and finish, was very good.  Also included was the manual, grille, grille removal tool, Allen head screws and bit, and speed clips.  MSRP is $550.

 

I love the design of the Hertz Audio Mille Pro MPS S4. It’s an extremely shallow mount deign with a mounting depth of only 3.5 inches!  It’s also just a single voice coil.  The cone is concave with the center cap sticking up and the space of the cavity behind the cap is filled by the magnet as the cone moves back and forth with the music. So when the cone moves back and forth with the suspension, the magnet fills the space right behind the cap.  This allows for very little space needed between the magnet and the top of the cone.  Yet thanks to its smart suspension design, it’s polypropylene cone squeezes out 16.8mm of Xmax! With an Fs of only 23Hz, this woofer is not only designed to move a lot of air, it’ll also play really deep! I can’t wait to see how it performs.

 

The design of the enclosure, size of the enclosure, and where it is located in the vehicle, can all effect how the subwoofer performs.  The test will feature a pair of subs mounted in a sealed enclosure with 0.9 cu feet of airspace for each subwoofer. They will be fed 1,000 watts RMS (500 to each sub) and will be sitting under the back seat of my 2017 Nissan Titan, down firing.  This setup may not be ideal for all subwoofers, but it’s the reality for a lot of vehicle owners. The testing will include measurements for response and output, and listening for sound quality.  Let’s see how it sounds.

 

Queen: Another One Bites The Dust-  bass beats were super clean, and really tight.  It hit really hard, and felt like a punch to the chest.

Branden Beal: Drop That Booty Down Low-  bass beats were so super clean, and played extremely deep.  They played with such a massive amount of authority.  My rearview mirrors really got dancing.  And when they dropped the booty down low, it was so massive like an earthquake in my truck!

Techmaster PB: Activate-  it played so so deep, and so loud doing so!  It really got my rearview mirror dancing.  My whole truck shook, like an earthquake it was so loud and deep.  I could even feel the SPL pressure build in the cabin.

Also Sprach Zarathustra-  it starts with a constant rumble of super deep bass, from the bows being run across the strings of the massive contra bass.  It was extremely clean. And there was enough resolution that you could actually hear the malets beating on the pad of the big tympani.  This was the musicality and resolution I was looking to hear from Hertz!  And they didn’t disappoint.

 

The Hertz Audio Mille Pro MPS 300 S4 was an excellent performer!  No matter what kind of bass was asked to be played, it was true to the source material.  Quick beats were extremely dynamic with great punch, yet deep sustained beats were also well sustained and shook the truck.  Its response was also very linear and had excellent output and flat response down to under 25hz!  And while I was extremely impressed with its output that I got to hit 130db, it was also very musical with great resolution!  After all, if you could get a subwoofer that was excellent in both output and sound quality, why wouldn’t you?

 

The Hertz Audio Mille Pro MPS S4 is a special product!  It hit really hard, and sounds great doing so.  It is also extremely unique in having a really low FS, frequency response, and linear response. And thanks to the Xmas as much as standard depth subwoofers, it even plays extremely loud at its published full frequency range.  It’s also very well made to provide years of use.  If you want killer sound quality with high output, the Hertz Audio Mille Pro MPS 300 S4 is worth the high price of admission.  Based on its design, features, quality, and performance, the Hertz Audio Mille Pro MPS 300 S4 has earned our Editor’s Choice Award.  For more info and complete specs, check out their website at www.hertz-audio.com.  Reference gear used: Kenwood Excelon Reference DNR-1007XR Receiver, Nakamichi NDST500A 12 Channel DSP 10 Channel amplifier, Wavetech Link 1000.1mini Subwoofer Amp, German Maestro M-Line 3-Way Component System, Alpine Type-X 2-Way Component System, Hertz Audio Mille Pro MPS S4 Subwoofer, SoundSkins Dual 12-inch sealed enclosure.