SPEAKERS AND SUBS
MTX Thunder T7512-44
By Paul Sonada
Posted on Thursday, Sep 16, 2004

Following up the release of massive 9500 series Superwoofers, MTX has broadened the line by adding the 8500 and 7500 series. Structured in a “Best, Better, Good” scenario, the T7512-44 is a 12-inch woofer that belongs to the “good” series with an MSRP of $249.95. So, how well does the MTX T7512-44 stack up to its larger siblings? Let’s find out.

First Look
The MTX T7512-44 is a 12 inch dual 4-ohm voice coil subwoofer. The T7512-44 is rated to handle 400 watts RMS. Although not directly stated, I did find some reference that peak power handling of the woofer was 800 watts. The T7512-44 includes two sets of 8 gauge binding post to connect the woofer to your amplifier. The black plastic cone is completely covered with an aluminum finish looking dust cap. The T7512-44 incorporates two layers of stitching to connect the cone to the rubber surround. The surround/top gasket is a one-piece integrated design. This ensures proper alignment of the T7512-44’s cone body to the black powder coated cast basket. The nicely styled MTX logo on the dust cap finishes the look of the woofer.

Closer Look
The engineers at MTX say that 90% of the technology used in the bigger brothers is used in the making of the T7512-44. When I took a closer look at the woofer, I noticed features usually reserved for higher end drivers. The most obvious of which is the tinsel leads. To maximize the reliability, MTX incorporated the tinsel leads into the asymmetrical flat spider. The tinsel leads are the main connection between the speaker outputs of the amplifier and the woofer’s 2.38 inch aluminum voice coil. These wires take the most abuse. Not only do they have to carry the entire amplifier current, they have to accomplish this while vibrating between 20 to 250 times per second.

The spider itself is designed to increase power handling by dissipating heat via “Spider Plateau Venting Technology.” When the woofer operates, the movement of the spider helps to push air in and around the voice coil. The air is allowed to vent underneath the spider through eight 1-inch holes that are covered with a cool silver mesh. The T7512-44 motor structure consists of an industrial machined top plate and solid bumped pole plate. MTX says that the pole is extended above the top plate to increase efficiency and woofer control. The top plate and pole plate encompass a pair of magnets that look perfect.

Manuals/Web Support
The manual for the MTX T7512-44 provides the woofers parameters and all the necessary information to wire and install the woofer. One of the nicest features about the manual is the drawings for building proper sealed and vented enclosures (ported for some of you). The plans are detailed and well executed. Also included was a nice tutorial on speaker wiring. This comes in handy for connecting the dual voice coils of the T7512-44 to your amplifier. MTX’s Web site, www.mtx.com, was easy to navigate. I quickly found the T7512-44 page that contained basic information about the woofer. The owner’s manual is also available for download on this page. On the down side, I would have liked more information about the technology used to create this fine woofer. On the plus side (way plus), MTX had a kick butt page that matches their woofers with their amplifier for optimal performance. Way cool! This handy chart is also available for PDF download.

Installation
The installation of the MTX is pretty standard. On thing that made the installation easier was the incorporated foam sealing gasket under the woofer’s cast mounting ring. This handy feature really makes for easy installation. Along with the woofer, I also received the Sledge Hammer enclosure. The fit and finish of the enclosure is top shelf. I internally verified that the wiring for the T7512-44 was set up for 2 ohms mono. If you look at the owner’s manual and find yourself unsure about the dual voice coil wiring, do yourself a favor and have an authorized MTX dealer perform the installation of the T7512-44.

Sound Q & Performance
The performance of the MTX T7512-44 was good — no, make that very good. Based on available enclosure information, tuning is around 40Hz with a lower posted frequency limit of 38Hz. My in car testing found the usable lower frequency limit to be a practical 30Hz. From 40 Hz to 70Hz, the T7512-44 was quite impressive generating 130.1dB with 400 watts RMS input. Doubling the power generated even better results. Peak SPL occurred at 50Hz at heart pounding 132.8dB. The sound quality of the MTX T7512-44 was very good. Kick drums sounded tight and techno bass had awesome impact. Only with the extremely low bass did the T7512-44 seem out of its element. Below 30Hz, there was no useable output. The increase seen on the chart was a result of higher frequency port and woofer noise. This was probably due to enclosure tuning and would most likely be better with the recommended sealed enclosure. For long term reliability, I would recommend a subsonic filter (infrasonic for you tweak heads) at 30 Hz. This would ensure long lasting hard hitting performance from the T7512-44.

Summary
The MTX T7512-44 combines great looks, excellent fit and finish and great SPL number in the 40Hz to 70Hz range. Never in my auditioning of the woofer did it lose its composure. In fact, even when I doubled the RMS power handling the T7512-44 held strong. MTX is definitely conservative about the performance of the T7512-44. If you are looking for a great sounding woofer with hard-hitting performance in the meat of your baseline, the MTX T7512-44 is your woofer.