Most of us have heard of many types of car audio subwoofer enclosures. Many enthusiasts have debated the benefits and drawbacks of acoustic suspension (sealed), bass-reflex (vented), bandpass and infinite baffle designs in hopes of choosing the best solution for their application and expectations. In all cases, the enclosure has two specific purposes that are crucial to ensuring that your subwoofer sounds excellent.

Rear Wave Cancellation

If you were to take a subwoofer out of its carton, connect it to an amplifier and play music, it wouldn’t make any bass. As the cone moves forward, the pressurized air in front of the cone is canceled by the rarefied air behind the cone, and vice versa. We call this back-wave cancellation.

In the graph below, you can see two sine waves, one in yellow and another with opposite polarity in blue. When they are added together, they cancel each other out, and you get the green line.

Understanding that the sound coming off the back of the subwoofer (or speaker) cone cancels the sound coming from the front is the first step in comprehending why a subwoofer needs an enclosure. We need to separate those two sound sources from each other for us to hear bass information.

The simplest solution is to create a wall or baffle that keeps these sound sources separate. That’s exactly what happens in an infinite baffle subwoofer installation. Your installer will either cut a hole in the rear deck of your sedan or mount a subwoofer on a board behind the rear seat so that you hear only the music coming from the front of the speaker. The sound coming from the rear is trapped in the trunk. This type of design doesn’t work with SUVs or hatchbacks since they don’t have a trunk to capture the sound from the back of the subwoofer cone. In reality, this is very similar to a sealed enclosure, except that the enclosure is extremely large and doesn’t affect the frequency response of the speaker.

Benefits of an Infinite Baffle Car Audio Subwoofer System

Infinite baffle installations are very popular in factory-installed subwoofers systems in sedans. The subwoofer can be mounted in the rear deck of the vehicle, and the trunk becomes the enclosure. These systems are also relatively easy to construct, as long as the trunk is sealed well. The drawback of this type of installation is that there is nothing to control the motion of the subwoofer cone other than its suspension.

Subwoofer Physical Power Handling

For a midrange driver playing above 300 Hz, cone excursion isn’t a concern because it doesn’t have to move very far at these frequencies. As audio frequencies decrease, cone excursion increases dramatically. As an example, to produce, say, 90 dB of output at 100 Hz, a subwoofer cone might have to move 1 mm forward and rearward. To produce the same output at 50 Hz, the cone needs to move 4 mm, and at 25 Hz, the cone will have to move back and forth a total of 16 mm. Stated scientifically, cone excursion at a given output level increases with the inverse square of the frequency. So, for each drop of one octave, excursion quadruples.

Every speaker has a limit as to how far the cone can move forward or rearward. While there are different methods of determining this limit based on acceptable distortion performance, we’ll use the Xmax standard of the voice coil needing to not move outside of the top plate.

In the case of this Sony XS-GSW101 subwoofer, Xmax is specified as being 6.4 mm in each direction. This definition means the cone can move through a range of 12.8 mm without the strength of the magnetic field imposed on the voice coil by the top plate changing. What happens when the voice coil starts to move out of the top plate? In short, the amount of distortion added to the output skyrockets because the cone movement isn’t linear relative to the drive signal. You don’t want that.

How a Subwoofer Enclosure Improves Power Handling

When we put a subwoofer into an enclosure, the air inside the enclosure acts to limit how far the cone can move. In a tiny enclosure, the total air volume is small, so the cone can’t move much. In a large enclosure, the volume of air is large and is easier to compress and rarify, so the cone can move farther.

The graph above shows how the compliance (resistance to pressurization and rarefaction) of the air inside a sealed enclosure affects the output of the system. The red curve shows the response of the subwoofer in an infinite baffle application. As you can see, there is lots of output down in the 20-40 Hz range. The white curve shows the sub in a 0.6-cubic-foot enclosure. It’s not as loud at lower frequencies. Finally, the blue curve shows the response of the subwoofer in a very small 0.2-cubic-foot enclosure. This is much smaller than you’d ever want to use but serves to show how the cabinet acts to limit cone travel and, consequently, bass output.

In the graph above, the three traces show us how much the subwoofer cone moves relative to the size of the enclosure at a drive level of 350 watts. The red curve is our infinite baffle simulation, the white is 0.6 cubic feet, and the blue is an enclosure with a net internal volume of 0.2 cubic feet. Since we don’t want the subwoofer sound distorted at high output levels, our installer needs to choose an enclosure design that balances bass output with maximum cone excursion capability. In this case, the blue enclosure is the only application where we can provide the full rated 350 watts to the subwoofer without the cone moving too far.

We did some extra simulations and confirmed that an enclosure volume of 0.29 cubic feet allows the full 350 watts of power to be applied without excursion issues.

I Want More Bass Than That!

If we look at the frequency response graph above, it shows us that our subwoofer has a -3 dB output frequency of about 92 Hz. While this doesn’t seem like much fun in terms of making bass, it actually works out OK because our vehicles boost low frequencies. The result would be relatively flat frequency response. What do we do if we want our subwoofer to play louder? The answer is to have the retailer you are working with build a bass reflex (vented) enclosure.

In the image above, you can see how much more bass the same subwoofer produces when installed in a vented enclosure. At 40 Hz, the vented enclosure is 9 dB louder than the sealed enclosure. At 30 Hz, it’s 8.2 dB louder. It seems like a win, doesn’t it? When you combine this increased output with the cabin gain, we find all vehicles benefit; suddenly a single 10-inch subwoofer can really rock!

Is there a drawback to using a bass reflex enclosure? The answer is yes. Below the tuning frequency, the enclosure doesn’t control cone motion well.

The violet curve in the graph above represents the typical cone excursion response from a bass reflect enclosure. The cone moves a little more around 55 Hz, but a lot less at 35 Hz, which is the tuning frequency of the vent. This is because most of the sound produced by the enclosure is coming from that vent. Below the tuning frequency, cone excursion skyrockets. Below 30 Hz, we can run into excursion issues. To prevent this from damaging the subwoofer, it’s best to implement a high-pass filter (often called an infrasonic filter, or incorrectly called a subsonic filter) to limit output at these frequencies.

Choose Your Subwoofer Enclosure Solution Wisely

Your car audio subwoofer needs an enclosure to prevent the sound coming from the rear of the cone from canceling with the sound coming from the front. Likewise, it needs an enclosure to control cone motion to prevent distortion at high drive levels at low frequencies.

When you visit your local specialty mobile enhancement retailer to discuss the prospect of upgrading your vehicle with a subwoofer, it’s important to talk about the style of enclosure that will be used. A design that helps to optimize the efficiency of the overall system can make your car stereo sound great while reducing the power required from the amplifier. When executed properly, even a single 10-inch subwoofer can deliver impressive bass response that will make your music sound amazing.

This article is written and produced by the team at www.BestCarAudio.com. Reproduction or use of any kind is prohibited without the express written permission of 1sixty8 media.

When it comes to upgrades and accessories for your Ford Mustang, your local mobile enhancement dealer has a nearly endless supply of options. Whether you’re shopping for a new radio with CarPlay and Android Auto connectivity, or you want new speakers, subwoofers and an amplifier to bring your music to life, there are thousands of options. The accessories available to personalize your Mustang are just about endless. Let’s take a look at some of the most popular enhancements.

Ford Mustang Audio System Upgrades

Whether you’re rocking a Fox-body or a Sixth-Gen, the options available to make the sound system in your Mustang better are nothing short of endless. Ford has offered upgraded systems like the Shaker 500, Mach 460 and the latest Bang and Olufsen systems. While they were better than a base-model radio and a few pairs of speakers, they pale in comparison to what you can get from a set of good-quality components, a subwoofer and a high-quality amplifier.

If you have a classic Mustang, then companies like RetroSound or Custom Autosound may have a drop-in radio that fits perfectly into your dash. These radios include modern technologies like Bluetooth hands-free calling and audio streaming, USB ports to play digital media files from a memory stick and digital tuners for better radio reception. Your local car stereo shop can help you choose new speakers that will fit perfectly in the factory speaker locations. Alternatively, they can build custom speaker mounting solutions for you that will improve the realism of your listening experience.

If you want modern technology in your classic vehicle, you may choose to have a custom console built for a double-DIN multimedia receiver that includes Apple CarPlay and Android Auto smartphone integration. Some of the more premium receivers will even connect to your phone wirelessly so that you can keep your phone in your pocket or purse.

On many newer Mustangs, you can have your installer interface a Sony, Alpine, Kenwood, Pioneer or JVC radio with the data network in the vehicle using the Maestro RR or RR2 computer. This data connection allows your aftermarket radio to display information like vehicle speed, engine speed, parking sensor warnings and the backup camera image.

Whether you have a classic or something fresh off of the showroom floor, the audio system upgrade path remains surprisingly similar. Adding a subwoofer to a factory-installed stereo system is one of the best single upgrades you can make. You can turn down the bass control on the radio, so the small speakers around the car don’t have to work as hard, then let the dedicated amplifier and high-excursion subwoofer ensure that the bottom few octaves of your music sound amazing.

Once you have great bass, the next step is to upgrade your speakers and add an amplifier. Better speakers are more precise and detailed while offering the ability to play louder without distorting. To maximize the performance of these speakers, you’ll need an amplifier that can deliver at least 45 watts of power per channel.

If you want a truly incredible audio experience, then consider having a digital signal processor added to your upgraded sound system. If you already have amplifiers and speakers, then a stand-alone processor can be added. If you are shopping for an all-new system, then consider buying an amplifier that has signal processing built-in.

Once the speakers and subwoofers are installed in your Mustang, your installation technician can use the equalizer built into the DSP to calibrate the system to compensate for the acoustics of the vehicle. The result, when appropriately executed, are voices and instruments that sound more realistic and detailed. Likewise, the technician can configure the system so that it feels like you are sitting in the front row of a concert or the middle of a club – with music all around you.

Remote Car Starters and Comfort Enhancements

If you live in a climate that’s bitterly cold in the winter or brutally hot in the summer, then upgrading your Mustang with a remote car starter is an excellent investment. You can start your Mustang a few minutes before it’s time to leave so that the climate control system has a head start in making the interior of the vehicle more comfortable. Be sure to ask your retailer about the different control options such as two-way remotes and telematics systems that work with an app on your smartphone.

If your Mustang didn’t come with heated seats, your installer should be able to add a set of heating pads that will make getting into the vehicle much more comfortable on a cold winter morning. The heating pads can be configured to work with the remote starter system.

Another great upgrade to make your vehicle more comfortable is window tint. Many companies offer high-quality tint films that reject a great deal of infrared heat energy from the sun. The result is a vehicle that doesn’t get as warm while sitting in the sun and that is easier to keep cool while driving.

High-quality window tint film also blocks almost all of the UV rays from the sun. This protects your skin against damage and helps to keep the interior of your vehicle looking like new.

Lighting Upgrades Improve Safety

Aside from your tires and brakes, the headlights on your Mustang are one of the most important safety items on the vehicle. Being able to see other vehicles, objects, and people when driving at night is crucially important. Many mobile enhancement retailers offer a variety of headlight bulb upgrade options. The latest generation of LED bulbs produce more than three times as much light as a standard halogen incandescent bulb. They also work well in most reflector (1987 through 2012) light assemblies as well as projector assemblies.

There are also many fog and driving light upgrades available. If your Mustang came with fog lights, there are white and yellow bulb upgrades that can increase the light output dramatically. If your car didn’t come with any auxiliary lighting, many companies make aftermarket lights that will bolt directly into the vehicle, and they may even work with factory wiring, if available.

Police Radar and Laser Detectors

We know it doesn’t take long to get into trouble in a Mustang. If you find that your speed tends to creep up beyond the legal limit now and then, you may want to consider purchasing a radar detector. A portable detector is a simple solution that can be moved from car to car. These devices provide long-range warnings when X, K, and Ka-band radar are being used. BlendMount offers a bracket that will attach your detector neatly to the rearview mirror in your vehicle, and an installation technician can conceal all the wiring for you.

If the police in your area are using laser (also called lidar), then you will want to invest in a custom-installed detector with a laser shifter system. These solutions can prevent the laser guns from measuring the speed of your vehicle. You can slow down quickly, then cancel the shifting signal so you can carry on to your destination without delay.

Cosmetic and Convenience Enhancements

A set of Mustang-specific floor mats from WeatherTech or Husky are a great way to keep the interior of your vehicle clean and tidy. These mats extend up the sides of the footwells to keep dirt, sand, mud, salt and slush out of your carpets.

Another great upgrade is a cell phone holder or charging base. Your retailer can add a bracket to hold your phone on your dash or the center console. Another option is to have a wireless charging base added so you can top off the battery without the need for additional wiring.

If your Mustang didn’t come with a backup camera, several solutions are available to add one to your vehicle. There are application-specific solutions that work with the color display of a MyTouch or Sync infotainment system that will show you what’s behind the car when you’re backing up. If your car doesn’t have a display, you can have a replacement rearview mirror added that includes an LCD screen.

Upgrade Your Mustang Today!

Whether you need a replace a worn-out speaker in a classic Mustang, upgrade the technology in a Fox-body or add a custom subwoofer solution, your local mobile enhancement retailer can make the stereo sound great. Drop by one of the specialty car audio shops in your area to see what they can do to make your pride and joy even cooler.

This article is written and produced by the team at www.BestCarAudio.com. Reproduction or use of any kind is prohibited without the express written permission of 1sixty8 media.

When it comes to ways to control the volume and tracking or seeking on a car radio, the three most popular options are rotary volume controls, pushbuttons and touchscreen interfaces. While many buyers focus on features like Bluetooth, Apple CarPlay, Android Auto and backup cameras when shopping, there’s more to consider. A key and often overlooked part of the process of choosing a new radio for your vehicle is to try the model you have in mind on a display board at a local specialty mobile enhancement retailer. Can you adjust the volume without having to look at the radio? Is it easy to change songs or radio stations? Can you change sources while keeping your eyes on the road? A radio that looks great but is difficult to use won’t be enjoyable – or safe.

What Is a Human-Machine Interface?

Whether it’s a car radio, a microwave oven or a computer, the controls we use to change settings or provide input to an electronic device make up a human-machine interface. Companies devote thousands of hours to developing what these interfaces look like and how they work. Some are incredibly intuitive, while others can be frustrating.

The first popular smartphone was the Blackberry. These compact devices had miniature keyboards that made entering text quick and easy. Later, companies shifted to touchscreens for a sleeker look. Many Blackberry users resisted the transition because there wasn’t any tactile feedback. You could enter two or three characters on a touchscreen without even knowing, while the pressure required to register a character on a mechanical keyboard was very distinct.

Classic Car Radio Control Options

If we think back to the ’60s and ’70s, car radios typically had two knobs: The left knob was the volume control, and the right one adjusted the tuner. No matter what car you got into, you already knew how to use the radio. These radios used analog potentiometers (variable resistors) for volume control functions. Even the DIN-and-a-half radios from Delco and Chrysler kept this same straightforward approach to adjusting the volume. An excellent interface is one that we can use without having to think about how it operates.

Rotary Volume Control Radios

In a single-DIN receiver, most modern solutions include a rotary volume control on the left side of the chassis. The analog potentiometer has been replaced with a digital encoder that sends commands to the microcontroller that manages all the radio functions. Likewise, on many models, this control also has an integrated pushbutton that allows you to change sources or access balance, fader, bass and treble controls.

On double-DIN radios, the availability of a rotary volume control depends on the size of the display. If you have chosen a radio with a 6.2- or 6.4-inch touchscreen, then there is likely room for a small volume control on the left side of the radio. This may be paired with a source button and additional buttons for track selection or preset adjustment.

The advantage of this design is that you can adjust the volume without having to take your eyes off the road. By reaching over to the radio, you intuitively know how to use the three buttons by feel.

Pushbutton Radio Controls

If you opt for a double-DIN multimedia receiver with a 6.95- or 7-inch display, then you’ll find they use a set of pushbuttons for volume adjustment. Depending on the size and placement of the buttons, this can still be a relatively intuitive solution. Look for units with separate physical buttons as opposed to smooth membrane switches.

Very few single-DIN CD and digital media receivers use pushbuttons for volume control.

A drawback of pushbutton volume controls is that they don’t let you adjust the volume quite as quickly as a rotary control. That said, most radio manufacturers include programming that increases or decreases the volume relatively quickly if you hold the corresponding button for about a second.

Membrane and Touch-Panel Controls

Though they may look sleek, the membrane switches or touch panels that let you make adjustments to your audio system are difficult to use while driving. If you want to change sources, adjust the volume or change tracks, you have to look at the radio, then press the corresponding area of the screen. Sure, the process may only take one second, but if you are driving on the highway, that means you’ve traveled about 100 feet. A lot can happen in that time.

Steering Wheel Audio Controls

Most cars come with buttons on the steering wheel that will let you adjust the radio volume, change tracks or change media sources. In almost every case, your installer can integrate these buttons into an aftermarket radio using a small computer module called a steering wheel control interface. Once it’s configured, you can make adjustments safely while you monitor your driving.

Some of the more capable interfaces allow your installation technician to configure multiple functions to work with a single button on your steering wheel. For example, your installer could program the interface to activate the voice recognition mode of CarPlay or Android Auto if you press and hold the Source button on the steering wheel for two seconds.

Test Your Radio Before Buying

As you can see, there are many options available to control your new car radio. Before you make a purchase, test the radio you have in mind on a display board at your local mobile enhancement retailer or in one of their demo vehicles. If you can’t make basic adjustments safely, then it might be worth looking at a different solution.

This article is written and produced by the team at www.BestCarAudio.com. Reproduction or use of any kind is prohibited without the express written permission of 1sixty8 media.

There are two reasons why we’d want to upgrade the speakers in our vehicle: the original speakers may be damaged, or we want to improve the clarity of the audio system. In either case, you’re going to need to visit a local mobile enhancement retailer and choose a speaker solution that fits your vehicle, works with your budget and sounds great. This will involve auditioning several options before you make a purchase. Not listening to speakers before buying them would be like trying to pick out a suit or choose a new paint color for your car while blindfolded.

Choose the Right Music

The first step in auditioning speakers is to choose the right music. You’ll want to pick something that you know well and have listened to on a variety of audio systems. You should listen to these songs, or portions of them, as much as you can before you go shopping.

It’s best to choose tracks that highlight certain aspects of a speaker’s performance. For example, a song with a solo vocalist is a good way to evaluate midrange tonal balance. Smooth response through the midrange is crucial as our hearing is very sensitive to these frequencies. Even subtle changes in midrange response are easy to detect.

You will want a track that demonstrates the overall tonal balance of the speaker. If we are looking at a coaxial or component speaker, then choosing a solution with energy from the midbass, midrange and high-frequency range is essential.

Where a great speaker separates itself from the mediocre is in its dynamic performance. There’s no such thing as a fast speaker. The ability of a speaker to respond to a transient signal is determined by its frequency response. What you want to evaluate is how fast the speaker settles after the signal is removed. Tracks with percussion, bass guitar or an upright bass are great for this. Does the speaker respond to a floor tom with a snap, or is it sloppy with lots of resonance? Does the pluck or strum of a string resonate clearly, or does it get shrouded in harmonic content?

Control All the Variables

When you go speaker shopping for your car, truck, motorcycle or boat, it’s likely that you’ll be listening to a display in a store. You’ll want to try to listen to music at the same volume level on every speaker you audition. Increasing the volume, even by a small amount, will make background sounds seem louder and more present. Higher volumes can also excite resonances in the room that will make it seem like a speaker is producing more bass.

Where the challenge of matching the output of one speaker to another gets exasperating is that it’s rare to find two different speakers with the same efficiency. Try as hard as possible to make things equal.

You’ll want to make sure there isn’t any equalization applied to the speaker. The tone controls on the source unit should be set flat. Some higher-end displays may include a digital signal processor. In these cases, ask whether each speaker solution has been matched to the same reference frequency response curve and target efficiency. If so, this is an ideal way to compare the performance of different speakers.

Consider System Design

If your car audio system will include a subwoofer, then how you audition a set of coaxial or component speakers will change. You should ask that a high-pass filter be applied to the speaker so that it’s not trying to make bass. In fact, you’ll find that speakers that seem to produce a little less midbass are often more accurate than ones that produce more.

Loudness or emphasis within a narrow band of frequencies is not an indication of quality. It’s usually a sign of unwanted distortion or poor design. Check out our article on Speaker Q for more information on this topic.

If you’ll be using the speakers without a subwoofer, then bass output matters. You may choose to trade some accuracy in the midbass region for more output. It’s a worthy sacrifice to make the system enjoyable.

What Will the Speakers Sound Like in My Car?

The problem with auditioning speakers in a showroom is that unless they have been equalized with a DSP to a specific target curve, you’ll hear something different once they are installed in the car. What you’re looking for isn’t the absolute response of the speaker, but the performance characteristics of the driver and how they differ from the other options. Your job is to pick out the speaker that sounds as accurate as possible. A speaker that is bright on the display may be annoyingly harsh in a vehicle. Likewise, one that produces a lot of midbass may sound very boomy or sloppy. If the speaker is neutral and accurate, then it’s likely to be a well-designed solution that will sound great.

Listen, Listen and Listen

When it’s time to shop for new speakers, audition as many options as is reasonable. Learn to pick out the performance differences between the options. You can start this process at home with a home stereo, a portable Bluetooth speaker and your smartphone and some headphones. Very quickly, you’ll be able to pick out a speaker that sounds right. Once it’s in your vehicle, you can have the technician tune the system to deliver the frequency response you enjoy.

Put a few songs you know well on a USB memory stick and head to your local specialty mobile enhancement retailer today. Auditioning new speakers can be a lot of fun and very educational. Done correctly, it ensures that your audio system will sound the best it can.

This article is written and produced by the team at www.BestCarAudio.com. Reproduction or use of any kind is prohibited without the express written permission of 1sixty8 media.