Review – Adding Some Bottom End by Installing a Pioneer TS-WX120A 150 watt Amplified Subwoofer System

In part four of our multipart story on upgrading the entertainment system in your vehicle, starting with a Pioneer 4100 NEX in-dash receiver, we concentrate on adding some oomph to your bass with an easy to install Pioneer TS-WX120A 150 watt Amplified Subwoofer System.

How to add bass to an automotive system isn’t unlike adding increased bass response to a home system or even a computer audio system. There are a few options. The first is to have primary speakers that have decent bass response. This is limited to size of the drivers, cabinets, and amplification. Many of the best speakers in the world have no need for a subwoofer, but when size enters the equation, the basic physics of needing to move some air for reasonable bass response becomes an issue. There are some small speakers that properly driven can reproduce bass quite wonderfully, but generally not in rooms that are noisy or too large.

Vehicles are inherently noisy, so having decent bass response requires overpowering in a sense the ambient road noise. While our initial upgrade included speakers capable of good bass response, it was limited, and bottom end bass needed some help beyond trying to manage it via EQ. A subwoofer to the rescue!

Subwoofers and how they interact with your system pretty much boils down to a few basic concepts. In an average home theater system, the AV Receiver can direct audio content below a specific frequency response to a dedicated powered subwoofer. This is especially easy with cinematic content, as the audio is specifically mixed and encoded with a .1 channel for low frequencies. Thus, pop a DVD or Blu-ray disc into a player, and the system will automatically cut off specific low frequencies to the primary speakers, and send to the subwoofer, and the same happens with most streaming content. This reduces the frequencies the primary speakers are meant to reproduce, and also reduces the load on the amplifier. The TS-WX120A’s 150-watt (50 watt nominal) Built-in MOSFET amplifier driving an aluminum woofer cone allows for a consistent and deep bass response. The 150-watt amplifier was powerful enough to drive just about any content we threw at it, from rock to jazz to NPR, to metal without colorization.

Ok, what the home theater approach has in common is digital content, with an encoded subwoofer channel, clean and easy. The problem and complexity comes in when you aren’t playing encoded content, such as what you might play in a vehicle. So, most AV car audio receivers don’t have digital specific feeds to a subwoofer, instead, you rely on crossovers of some sort. The subwoofers themselves are pretty simple, a large bass specific driver, coupled to a dedicated amplifier. These installations can range from a small all-in-one unit, such as the Pioneer TS-WX120A Subwoofer, to monster installations with custom designed speaker cabinets that take up much of the room in your trunk, or even the back seat of the vehicle, all coupled with some seriously powerful amplifiers and carefully designed and customized crossovers. These are the systems that make all the vehicles shake as they go by, and enrage residents trying to sleep. But hey, what do you expect when you have 500 watts feeding dual large subwoofers!

In our case, because we have a van, there really isn’t a way to install large subwoofers without compromising the usability of the van, so we opted for the kind of installation that most consumers would choose, an all-in-one low profile model that could mount under a front seat. This is an affordable, almost invisible (it measures only 8" x 5-1/4") upgrade to your vehicles audio system. Fortunately, upgrades like the Pioneer NEX systems, are designed with subwoofer upgrades in mind. To be honest, after the NEX and speaker upgrades we thought we were finished, but when Mike Fusco, General Manager of The Sound of Tri-State, the vendor who performed the installation work asked why we weren’t adding a subwoofer, we didn't really have a good answer, except that the system sounded very good as it was. But, I had to admit that I had been trying to increase low-end bass response via the graphic equalizer, without impacting and muddying the mid-tone response with limited success. So when Pioneer offered us the opportunity to review the Pioneer TS-WX120A Subwoofer we thought it would be a solid example of a simple upgrade with significant audio rewards. And we were right.

As per our recommendation in part two of this series, we don't feel the installation of the sub was an easy DIY job. So, we relied again on the talented folks at The Sound of Tri-State to install the unit. One advantage of the Pioneer TS-WX120A Subwoofer is that it’s only a few inches in height, so it easily fit under the drivers seat. It’s black, and unless you are looking under the seat, it’s invisible. There is one visible cue that the unit is installed is the addition of a small black remote control, which in our case was mounted with Velcro on the bottom left of the dash near the steering wheel. With the remote you can adjust Gain (volume), Phase, and the crossover via Frequency Response, so you can dial in the point where the sub kicks in, as well as how loud it was. In our family it turned out each of us had a slightly different preference. My wife kept it dialed pretty low, liking the believable bass boost to spoken word, while I liked a middle ground, with a solid, yet not overbearing boost to the bottom end, and our son the bass player liked it boosted a bit more, but not too much since he knows how a bass should actually sound.

Because the NEX system doesn’t have the ability to digitally dial in a bass cutoff, you can use the sub somewhat gently, since the other four primary speakers are still reproducing low frequencies, and if you aren’t attentive you can overdo the bass. This might not bother someone who wants the bottom end to rock the neighbors, but if a more musical and believable audio experience is your goal I’d suggest playing with both the graphic equalizer and the remote control for the sub for the best performance.

Was the upgrade worth the effort and expense? In our experience that is an absolute yes. The bass response was noticeable no matter the road noise, and the boost varied from gentle, to loosening your fillings. It didn’t have the shake the doors off of larger, component level installations, but that was fine with us, and we suspect most consumers for whom the primary purpose of a vehicle is as transportation, so not impacting the trunk space, or floor space is a primary concern. Aesthetically, it’s a well-designed unit with solid build quality, and the audio experience was free of distortion and coloration. Our unit went under the drivers seat, but we could have installed it under the passenger seat, or between the front seats. It could also have been installed in the trunk area, but since the van’s rear seat folds down into that cavity, that would have prevented the van from having a flat cargo area, so the front seat was the most logical spot.

There are many rationales to upgrading your vehicles audio system, and believable bass response is often the difference between average versus exemplary audio. In short everything we listened to sounded demonstrably better, from digital FM radio to high-resolution FLAC files from HD Tracks on a SD card the sub made an instant improvement. For an older vehicle without a good factory installed audio system, adding the Pioneer TS-WX120A Subwoofer is an affordable, easy, effective, and great sounding upgrade and comes highly recommended.

Harris Fogel, with additional reporting by Nancy Burlan, posted 1/30/2017

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