More and more companies are offering motorcycle audio system upgrade solutions. Bikes like Harley-Davidson Road Glide and Street Glide can sound so much better with proper speakers and a high-power amplifier. In this article, we’ll cover four things you need to keep in mind when shopping for new tunes for your touring bike.

1. Installation Is Crucial to Performance and Reliability

How the new speakers, amplifier and perhaps a new radio are mounted, wired and configured plays a considerable role in the performance and reliability of your motorcycle audio system. New speakers are often much more substantial than the factory-installed products they replace. The speakers need to be mounted securely with corrosion-resistant fasteners. Of course, the speakers need to fit perfectly and seal tightly against the faring face for optimum performance.

Amplifiers can draw a lot of current from the battery and charging system when the volume is cranked. High-quality, appropriately sized wiring with solid electrical connections is mandatory to get the most efficient delivery.

2. Buy from a Brick-and-Mortar Retailer

If you’re going to have work done to your motorcycle, make sure that it’s by someone who will be available to support the products and services they sell you. Many bike enthusiasts buy audio upgrades at shows and rallies. If you have problems or need adjustments weeks or months after the purchase, you’ll need to find someone else to help and you’ll have to pay them for their time. Dealing with a local shop that specializes in motorcycle audio can save you a lot of headaches. A deal at a show isn’t a deal if you have to invest more money down the road.

3. Choose Premium Products

Face it: Your motorcycle is likely worth a lot of money. Inexpensive speakers and amplifiers aren’t apt to perform well or last as long as products from reputable companies. A motorcycle presents a challenging environment for audio equipment. Vibration is a huge factor, and when poorly designed audio components are used, they often fail in a few months.

Amplifiers need to be designed so that they are efficient and reliable — the fragile components inside need to be secured so that nothing will break. Speakers need to be weather-resistant in case you get caught in the rain. You also want a solution that is designed to handle prolonged UV exposure without drying out, chalking, cracking or fading. Woofer cones that fade or change color after prolonged exposure to the sun may become more brittle and eventually crack and fail. Regular car audio speakers simply aren’t a reliable option.

If you’re upgrading the radio on your bike, be sure to choose something that is weather resistant. You want a bright screen that’s easy to see in direct sunlight. You will also want something that can integrate with the handlebar stereo controls, if your bike has them.

4. Audio System Upgrades Need Tuning for Accurate Sound

We may have beat this topic to death, but it’s worth stating at least one more time. The factory-installed radios in 2014 and newer Harley-Davidson touring bikes have a slew of signal processing built into them. If you don’t address this tuning when upgrading the bike with a new amp and speakers, the system likely won’t sound right, and you could damage the new components. A reputable mobile enhancement retailer should have the tools to check the output of the radio on a Honda, Yamaha or BMW bike before they dive into an upgrade.

Your best bet is to purchase a digital signal processor (DSP) from the shop installing your equipment. They can use their audio test equipment to smooth the EQ curve in the radio and fine-tune the system to sound the way you want. Having the radio flashed to reduce the equalization settings is another option, but this process could be undone if you take your bike in for service. Likewise, there may be concerns about your warranty when you make alterations to the software.

Upgrade the Audio System on Your Motorcycle Today!

If you can’t crank the stereo on your motorcycle to the point that it gives you goosebumps, drop by your local specialty mobile enhancement retailer today and find out about the upgrades that are available. Don’t be afraid to research the suitability and reliability of their suggestions before you make a purchase. In the end, a little planning will keep your investment sounding great and last for years.

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 seems to be some misunderstanding about the relationship between subwoofer mounting depth requirements and performance relative to enclosure volume. We constantly see enthusiasts talk about having a 10-inch shallow sub mounted under a car or truck seat. Their expectation is full-size subwoofer performance without the need for a large enclosure. Let’s do a few simulations to see if they have any hope of getting the bass they want.

What Is ‘Great Bass’?

In our opinion, the purpose of a subwoofer is to extend the low-frequency output of an audio system such that the entire audio spectrum is covered. Unless they are massive (which causes other problems), the speakers in your doors or dash won’t play much below 50 Hz at high volume levels. The addition of a dedicated subwoofer with a dedicated amplifier can easily play to 20 or 25 Hz and relieves the smaller speakers of the task of playing these frequencies. As a result, the smaller speakers will sound better, and the subwoofer will give you the impact you expect from your audio system.

When quantifying bass performance, we talk about output capability and extension. Quantifying these characteristics is tricky, as the numbers depend on the vehicle into which the products are installed. Instead, we’ll use simulations from the BassBox Pro software to give you an idea of how different subwoofers perform in compact enclosure volumes. While not absolute in terms of in-car performance, the relative differences will be demonstrated clearly.

Sample 1 – Rockford Fosgate Subwoofers

Rockford Fosgate has dozens of differently sized subwoofers in their product line. Their solutions range from affordable entry-level products in the Prime Series to competition-grade Superwoofers in the Power Series. For this comparison, let’s look at a Punch P3 shallow 10-inch subwoofer and compare it to a full-depth version at the same feature level. The two subs will be the shallow-mount P3SD2-10 and the full-depth P3D2-10.

Because space is usually at a premium for shallow subwoofer installations, let’s take a look at how each of these subwoofers performs in a compact sealed enclosure with a net internal volume of 0.5 cubic foot. If you want to picture that enclosure, it might have a width of 13.5 inches, a depth of 5 inches and will need to be 22 inches long if constructed from ¾-inch-thick material (as it should be).

It would be easy to think that the shallow sub plays louder, as the peak output is 109.7 dB at 106.7 Hz compared to 109 dB at 75 Hz for the big driver. However, in almost every application, your subwoofers will be used with a low-pass filter that’s set somewhere around 60-70 Hz. As such, it’s the system efficiency below 70 Hz that will determine how much bass the sub produces for a given power level.

The P3D2-10 simulation predicts 103.2 dB of output at 40 Hz and 101.8 dB from the shallow sub at the same depth. In this case, the big woofer will be louder for a given enclosure size.

Sample 2 – JL Audio Subwoofers

Another company with a great selection of full-depth and shallow subwoofers is JL Audio. Let’s look at the big 10W3v3-4 to the shallow 10TW4-D8 driver. The big sub needs at least 5.93 inches of mounting depth, while the shallow TW3 driver requires only 3.25 inches. Let’s look at both of these drivers in a half-cubic-foot enclosure and see which is louder.

Here we see that both subwoofers are very similar below our crossover frequency. The big W3 sub is producing 102.9 dB at 40 Hz, and the shallow TW3 driver offers 102.6. In our opinion, that’s pretty much the same.

Sample 3 – Kicker Subwoofers

Let’s run these calculations one more time with a pair of Kicker subwoofers. This time, we’ll compare the 10-inch square dual-4-ohm L7R sub to its shallow-mount L7T brother. Both drivers are rated for 500 watts maximum power handling. The L7R requires 6.125 inches of mounting depth, while the L7T needs only 3.75 inches.

Just as with the JL subwoofers, the output of the shallow subwoofer is very similar to that of the big sub when driven with 300 watts of power. The L7R’s predicted output is 103.7 dB at 40 Hz, with the thinner L7T is calculated to produce 104.3 dB. You might be able to hear the difference, but not likely.

Are Shallow Subs the Same as Deep Subwoofers?

As one of our readers asked on Facebook, “So, the benefit is only shallow mounting depth, not a change in enclosure requirements?” He is right. The physics that govern output and low-frequency extension don’t change with a shallow subwoofer. Their benefit is minimized mounting depth, not magical deep-bass from microscopic enclosures. Your installer can create unique low-profile enclosures with a shallow sub, letting them mount them in spaces where a full-size sub doesn’t fit.

One thing to keep in mind is that shallow subwoofers may not have as much cone excursion capability as their full-sized brethren. The Kicker L7R has an Xmax spec of 13.9 millimeters, where the L7R is only 9.2 mm. The full-depth Rockford Fosgate P3D2-10 has an Xmax of 15.2 millimeters versus 8.4 mm for the shallow P3SD2-10. The chosen JL Audio subwoofers are the exception here. The TW3 has a rated Xmax of 15.2 millimeters, where the W3v3 sub is 14.0 mm. Both are good numbers, so it’s not a concern.

Do Shallow Subs Work in Small Enclosure?

The answer to this is that every subwoofer needs a certain amount of air volume behind the cone to perform. Subwoofers with shallow designs don’t produce more deep bass from a small enclosure. We’ve heard both deep and shallow subs in 0.2- and 0.3-cubic-foot enclosures. They sound terrible. Our take-away from this series of simulations is a recommendation to resist asking the local specialist mobile retailer you are working with to design and fabricate an enclosure that doesn’t provide the subwoofers you’ve chosen with adequate space. You’ll likely find that you’ll get more deep bass by using fewer subs in a properly designed system.

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.

If you’ve been a reader of BestCarAudio.com, you know we’ve published a lot of articles about distortion. We include detailed measurements of harmonic and intermodulation distortion in our Test Drive Reviews to help show you the quality and performance differences between products. In this article, we’ll make a series of speaker distortion measurements using our new Clio audio analysis hardware to explain why investing in the best quality speakers you can afford is crucially important.

An Overview on Distortion

Before we start talking about distortion, we ask that you forget about amplifier clipping. That’s not what we’re talking about here. Yes, clipping IS the addition of significant amounts of unwanted information to an audio signal. With that said, clipping should only happen when an audio system isn’t designed or operated correctly.

The distortion we are discussing happens in low, mid and high volume levels and comes from every component in the audio signal path. Source components in an audio system add a small amount of distortion. Quality amplifiers shouldn’t add much unwanted information when operated in their linear range. On the other hand, speakers can easily add a lot of distortion.

Any time information is added to the original recording, that’s distortion. It could be hiss from an improperly configured processor or harmonics from a poorly designed amplifier. Have a look at this article (https://www.bestcaraudio.com/what-do-better-car-audio-amplifiers-sound-like/) that discusses the performance differences between low-, medium- and high-quality car audio amplifiers to get a feeling for just what they add to an audio signal.

Let’s look at a theoretical example of distortion before we dive into measuring any speakers. Imagine that we’ve created a single-frequency test tone to evaluate the distortion characteristics of audio equipment.

The graph above shows a spike at 1 kHz. There’s nothing else of significance in the display.

Next, we might play the above recording of a 1 kHz tone through a medium-quality source unit. Though it can be subtle, every audio component will add a number of harmonics to the signal. The output of our head unit might look like the graph below.

The graph above shows the same 1 kHz tone, but harmonics have been added to the signal at 2, 3, 4 and 5 kilohertz. The loudest harmonic, measured at 80 dB below the original signal, would represent a signal distortion of 0.010%.

The source unit has added information to the audio signal that wasn’t in the original recording. For example, the small spike at 2 kHz is second-order harmonic, the spike at 3 kHz is third-order, and so on. The relative level of the even and odd harmonics can give the audio component a harsh sound or make it sound unintentionally warm. Either way, the sound has changed from the original recording, and that’s not what we want any audio device to do.

Passing that slightly distorted audio signal into an amplifier will have the same effect. It will create multiples of any and every frequency that passes through it. So, it will add more unwanted information at 1, 2, 3 and 4 kilohertz, along with harmonics of each of those frequencies as they were present in the signal going into the amp. Below about -110 dB, you aren’t going to hear that information. We’ll get into another deep discussion of intermodulation distortion as we prepare to evaluate speaker configurations.

Let’s Test a Car Audio Speaker

It’s easy to create a low-quality speaker. Guess at a cone mass, pair that with some random voice coils, spiders and surrounds, then glue them together, plop those parts in existing baskets and put a label on the box. If you think there are speakers on the market that aren’t created this way, you’re wrong.

A good speaker is typically designed backward, from a target performance objective. For example, the aim could be a smooth response through a particular range of frequencies, enhanced low-frequency extension or maximum output efficiency. Most often, a group of these characteristics are combined during the development phase. Once the guidelines have been established, an engineer can model different components in simulation software. Once a plan is in place, parts can be developed to hit target mass, dimensional, compliance and electrical characteristics.

The companies with a wealth of knowledge in designing and testing speakers have a foundation for what works in each application. As such, hitting a target performance goal is more efficient and the results more accurate. Some companies use test equipment that combines acoustic measurements with laser-based cone movement measurements to evaluate samples and adjust or fine-tune the design. Hardware like this is available from Clio and Klippel.

No matter how hard the engineer tries, designing and producing moving coil loudspeakers is challenging. A little too much or too little glue can change performance. A misalignment of the vertical height of the coil to the cone and spider can result in non-linear performance. It’s easy to get this all wrong, and as such, it’s difficult to produce speaker products that are consistent in offering excellent performance.

Let’s Measure Speaker Distortion

We will start this evaluation of speaker distortion by testing a 6.5-inch coaxial speaker that was introduced to the car audio market in 2004. I knew from the first time I heard it that there was something odd with the design. First, there’s a sharpness in the upper midrange that’s quite unpleasant. The second reason I chose this driver is that it has the tweeter mounted right at the base of the woofer cone. (Why this is important will be revealed in an upcoming article.)

Let’s set the speaker up in my 2.2-cubic-foot test enclosure and measure the driver’s frequency response at a drive level of 1 volt and the microphone at 0.5 meter. The results are in the graph below. Ignore what’s happening below 30 Hz – those are room reflections.

The measurement above tells us a few things. First, there’s a nasty dip of 10 dB at 5 kHz and a second dip that extends from 6.5 to 7.4 kHz. Second, it also has a LOT of energy in the top end, rising steadily from 2 kHz to be almost 10 dB louder than the midrange level. Even if these measurements don’t correlate directly to what might be found in an anechoic chamber, they give us a clear idea about what’s going on with the speaker design.

Let’s Look at Distortion

The Clio measurement system can measure total harmonic distortion and precisely quantify second- and third-order harmonic content. So let’s sweep this speaker again at the same drive level and look at the distortion output. Once again, please ignore the bass information below 30 Hz.

The red trace is the measured frequency response of the speaker that we saw previously. The blue trace is the level of unwanted second-order harmonic distortion. The green trace is the level of third-order harmonic distortion. Finally, the violet trace is the sum of all the distortion content produced by this speaker.

To clarify these measurements, when the speaker is fed a signal at 200 Hz and reproduces that tone at an output level of 85 dB, it will also produce output at 400 Hz at a level of 42 dB and 800 Hz at 34 dB. The 400 and 800 Hz sounds were NOT in the original recording. These characteristics repeat for every audible frequency. So tones at 201 Hz have 402 and 804 Hz harmonics added, 202 Hz tones have 404 and 808 Hz harmonics, and so on across the entire frequency spectrum.

We can see that below 500 Hz, distortion increases quickly as frequency decreases. This phenomenon becomes clearly apparent at about 125 Hz where the total distortion jumps to 21 dB below the primary signal. That’s equivalent to about 10% THD. From 500 to 1 kHz, the distortion level is fairly constant at around 45 to 50 dB below the fundamental signal. That works out to between 0.3 and 0.5% THD.

The type of distortion that is added changes based on frequency as well. Below 500 Hz, the distortion is primarily the second-order blue trace. This kind of distortion is usually because of variances in suspension compliance and magnetic field linearity. Above 500 Hz, the distortion becomes primarily third-order, which can be attributed to changes in inductance. Above 1 kHz, distortion is usually based on cone and surround resonances. When we refer to changes in a characteristic, we are talking about variations in cone position and drive level.

The Tip of the Iceberg in Speaker Distortion

As mentioned, this is a preliminary introduction to speaker distortion. We’ll follow up with additional tests on speakers over the next few months to help explain the differences between low-quality and premium solutions. In the meantime, if you’re shopping for speakers, let your ears do the math for you. Drop by your local specialty mobile enhancement retailer to audition the upgrade solutions available for your car or truck.

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.

If you’ve scheduled an appointment with a local specialty mobile enhancement retailer to have your car or truck upgraded, there are a few things you’ll want to know to make the most of this opportunity. Whether the upgrade involves a new set of speakers, a multimedia receiver with a backup camera or a remote car starter, having the vehicle in a condition that will ensure that the technician can get to work quickly can save a lot of time. We’ve put together this simple guide to help make you a better customer and ensure that your project is completed on time and budget.

Please Arrive on Time

Mobile enhancement retailers work on a schedule. They’ve scheduled your car or truck for a certain amount of time to accomplish a task. In most cases, other clients are scheduled before and after you. If you show up five or 10 minutes late, that’s not only frustrating, but it can affect the entire day’s schedule and put other customers’ projects behind.

If you have an appointment, we suggest showing up about 15 minutes early. This extra time will give you and the product specialist a chance to confirm the details of the installation and allow the technician to pull the car or truck in and get the product prepared. If you’re having a new multimedia radio installed, the shop may have questions about where a USB connection for CarPlay and Android Auto should be located. If the upgrade is a remote starter, you and the specialist might want to review options like trunk or hatch release or automatic rear window defroster activation. In most cases, these items would have been covered before the quote was provided, but it’s always worth talking about as it’s easier to add them at the time of the installation as opposed to a few weeks or months later.

Please Bring What’s Required

In the rare case where you have the equipment to be installed in your possession before an installation appointment, please be sure to bring it with you. This applies to audio installations as well as remote starters. Many times, the starter and accompanying installation have been purchased in advance so the system could be presented as a gift. Make sure you bring everything with you on installation day. If you’ve opened the package, be sure to put everything back. A missing harness or remote might prevent the project from being completed and could result in additional costs.

Speaking of remote car starters, the specialists at the retailer you are working with might have asked you to bring both keys for the vehicle. This may be necessary to program the interface module to the vehicle. Without them, the installation can’t be completed. If you aren’t sure if you need to bring both keys, please bring them anyhow.

Would You Mind Taking Your Stuff Out of the Vehicle?

This is one of the biggest frustrations for installation technicians. Imagine you’ve scheduled your car or SUV for a subwoofer system installation, but the cargo area is full of sports equipment, work supplies or tools, or even purchases from a recent shopping trip. The technician will need to spend time moving these items before they can start work. This extra work can easily add five minutes to the beginning and end of each project. By the end of the day, it’s not unreasonable for them to have wasted half an hour just moving personal belongings when they could have spent that time upgrading client vehicles.

If you have an appointment, empty your vehicle. Start at the front and work backward with a basket or bag. Empty the center console, the storage compartments in the doors, items from the floor and the back seat. Clear out the cargo area of any items as well. Please do these things even if you don’t think those areas will need to be accessed. Sometimes a technician will have to run wiring through the vehicle for a remote starter or audio system installation. Anytime there’s stuff in the way, time is wasted. Trust us when we say that they appreciate you having the vehicle ready.

Give the Vehicle a Quick Cleaning

It only takes 15 minutes to run a car or truck through a touchless car wash before an installation. Getting dirt and debris out of the door sills will help a technician installing a remote starter stay clean. Clean fenders and the area around the trunk or hatch can prevent scratches, even if a fender cover is being used. The technician working on your vehicle will need to access the battery if an amplifier installation is involved in an upgrade, so they will be moving all over the vehicle.

If you can, vacuum the interior before you show up for an appointment. Some of us are fanatical about keeping the interiors of our cars and trucks clean – some aren’t. Nobody wants to work around old drink cups, food wrappers, stray French fries or used straws. If you can vacuum out sand and gravel, our floor mats will be cleaner for the next client.

Winter Installation Appointments

You can do a few things to help us work more efficiently when it’s cold out. First, if possible, please visit the car wash just before you arrive. Getting as much slush and snow off the vehicle and out of the wheel wells reduces dripping and puddles as the vehicle warms up in our bay.

If we have to remove interior trim panels from the vehicle to install a radio or speakers or run wiring, things go much better if the car has warmed up. Plastics are more fragile when they’re cold. The last thing we want is for something to break. If we’re having a busy day, it might be difficult to factor in time to let the interior warm up. If you’ve got the car up to temperature and the heater’s been on, we can get to work right away and ensure that your vehicle leaves our bay in the same or better condition than when it arrived.

Your Local Specialty Mobile Enhancement Retailer Says Thanks

It’s not easy to run a mobile enhancement business. Anything you as a client can do to help every project run smoothly and efficiently is genuinely appreciated. If there’s an audio component that needs to be replaced, if you’re interested in getting better sound from your stereo or are shopping for a remote car starter to make your vehicle more comfortable, please drop by one of the specialty mobile enhancement retailers near you. They’d be happy to help!

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.