Tuesday, October 24, 2023

Old School MTX Thunder Bandpass Subwoofer Box - Sold at Circuit City

In this article, we will be taking a closer look at an old school MTX Thunder bandpass subwoofer box. This particular speaker box was sold at Circuit City back in the day and features two 10-inch drivers inside. We will examine the construction of the box, clean the interior, and explore the woofers. Additionally, we will discuss the specifications of the MTX Thunder subwoofer box and its compatibility with the MTX Blue Thunder Pro amplifier.

Introduction to the MTX Thunder Bandpass Subwoofer Box

I recently had the opportunity to acquire a unique speaker box, the MTX Thunder bandpass subwoofer box. A generous individual contacted me and offered this cool speaker box, and I couldn't resist. So, let's dive in and take a closer look at this vintage piece of audio equipment.

The MTX Thunder Bandpass Subwoofer Box

The MTX Thunder bandpass subwoofer box is a single reflex bandpass box that houses two 10-inch drivers. The box features ports on both sides and has a single terminal. Upon initial inspection, the box appears to be a little dirty on the inside, so I decided to remove the Plexi panel to get a better look at its construction.

Inside the MTX Thunder Bandpass Subwoofer Box

After removing the screws, I lifted the Plexi panel and was pleasantly surprised by its thickness. The panel is approximately a third of an inch thick and has a gasket seal all the way around, ensuring a snug fit. However, the inside of the box did require some cleaning, as it was a bit dirty.

Examining the Woofers

Next, I proceeded to take a closer look at the woofers inside the MTX Thunder bandpass subwoofer box. I carefully pulled out one of the 10-inch drivers and noticed that the wires connecting it were surprisingly small. The woofer itself appeared to be a standard model from that era, with a foam surround that had not deteriorated. However, the wiring was inefficient and insufficient, with wires that seemed to be around 20 or 22 gauge.

Upon further inspection, I disconnected the driver and observed some bugs and spiders on the back. It's a good thing there wasn't any spider activity inside the box. The wiring definitely needed an upgrade, so I decided to replace it with larger gauge wire for better performance.

Cleaning the Box and Reassembling

Before vacuuming out the box, I took a moment to examine the inside and noticed a date stamped on the interior. The box also had two and a half inch ports and a terminal cut with small speaker wires. After vacuuming out the box to remove dirt and dust, I reassembled it, using the original small gauge wires to keep it as close to its original design as possible.

Cleaning the Acrylic Panel

The Plexi panel of the MTX Thunder bandpass subwoo fer box had some scratches and dirt on it. To clean it, I used a product called Novus Plastic Clean and a microfiber towel. I applied the cleaner to the panel and gently wiped away the dirt and scratches. While some of the deeper scratches remained, the panel looked much shinier and cleaner than before.

Shop for Novus Plastic Clean on Amazon*: https://amzn.to/3Fy9P2t

Testing the Speakers and Amplifier

With the box cleaned and reassembled, it was time to test the speakers and amplifier. I used an MTX Blue Thunder Pro 1502 amplifier to match the vintage style of the subwoofer box. The amplifier was wired up with eight gauge wire and bridged for optimal performance. I used 16 gauge wire to connect the amplifier to the subwoofer box.

The sound produced by the MTX Thunder bandpass subwoofer box was impressive. The deep bass tones were best experienced with headphones or quality speakers, as computer or iPad speakers may not do justice to the audio quality.


In this article, we explored the MTX Thunder bandpass subwoofer box, a vintage audio equipment sold at Circuit City. We examined the construction of the box, cleaned the interior, and discussed the woofers. Additionally, we tested the subwoofer box with the MTX Blue Thunder Pro amplifier, resulting in a satisfying audio experience.

If you're interested in learning more about the MTX Blue Thunder Pro amplifier, be sure to check out willistonaudio.com, where a full video of the amplifier's dyno will be released. Thank you for reading, and until next time, keep enjoying the music!


  • 1999 Car Audio and Electronics Directory
  • *Amazon - Novus Plastic Polish is an affiliate link

Tuesday, February 14, 2023

Michael Sears Electronics - Black History

Michael Sears


Michael Sears Electronics

In 1976, Michael Sears received an electronics kit which inspired his interest in electronics. 18 years later, he designed and introduced his own car amplifier, the Sears Electronics Model 2100HDP. Sears designed the amplifier using his own brain and a calculator, and it included a unique Automatic Power Control protection system. Sears opened his own electronics repair shop after serving in the army and working for cable and telephone companies. The Sears amplifier has received positive reviews, but he has only managed to finish and sell five units.

Prototype Michael Sears Electronics 2100HPA

Despite only selling a few units, the Sears Electronics Model 2100HDP has generated a lot of interest, with calls for information coming in from all over. Those who have used the amplifier have praised its power and sound quality, with one loyal supporter even winning first place in a competition with it.

Sears' interest in electronics began during his adolescence when he spent hundreds of hours working on various projects while his friends played sports and socialized. He later served in the army as an electrician and worked various tech jobs before opening his own electronics repair shop in his cousin's garage. It was during this time that he noticed that many car amplifiers had similar issues with power supply burnout and weak output.

Circuit Board of the 2100HDP

Although Sears didn't expect to do better than other companies at first, he saw an opportunity to develop a better design for car amplifiers. His use of a Casio calculator was key to the design process, allowing him to write custom programs that he couldn't do with computer-aided design (CAD) software. The resulting amplifier includes custom programs for wire resistance, amplifier power, and "maximum junction temperature," as well as the unique Automatic Power Control protection system.

While Sears has only managed to sell a few units of the Sears Electronics Model 2100HDP, he gained recognition in and around Elizabeth City, NC. He had loyal supporters, such as Kenny Proctor and Jesse Purkett, who enthusiastically spread the word about the power and sound quality of his amplifier.

Despite only producing and selling five units, Michael Sears had already generated a buzz in the audio industry, and many people were eagerly waiting to see what he would create next. Sears was not only skilled at designing audio equipment, but he also had a talent for marketing and generating interest in his products.

After the success of the 2100HDP, Sears continued to develop new audio products, including a line of high-end car audio amplifiers that received critical acclaim. However, he faced challenges in scaling up production and distribution, which limited the availability of his products and prevented him from reaching a wider audience. He designed several models for the company Dr. Crankenstein, including the DC3200. This amplifier had a retail price of $2799 and was said to produce nearly 4000 watts, an incredible feat in the early 90’s. 

Today, Michael Sears is recognized as a pioneer in the car audio industry, and his legacy lives on in the innovative designs and technologies that he created. Unfortunately, Michael Sears passed away in 1995 in an automobile accident. His story serves as an inspiration to aspiring engineers and entrepreneurs, demonstrating that with hard work and determination, it is possible to achieve success and make a lasting impact in any field.

Note: if you have a Michael Sears Electronics amplifier, no matter the condition, please contact me as I would love to share it with the car audio community along with Michael's story with help of his brother Steve.

Michael Sears and his 2100HDP Amplifier