For well more than a decade, respectable mobile enhancement retailers around the world have understood the need for a digital signal processor to be included in any car audio system upgrade. Even if you’ve chosen the lowest-distortion speakers on the planet and your installer has agonized over placement and integration, they still need a way to compensate for the peaks and valleys in the frequency response that come with the confines of a vehicle interior. The same process is used to calibrate home and commercial theater systems, recording studios, clubs and concerts. Let’s look at a few reasons why having a DSP in your system is crucial to achieving realistic sound.

Accurate Crossover Settings

One benefit of having your installer tune your audio system with a DSP as opposed to an analog processor with knobs is accuracy. The potentiometers used on amplifiers and stand-alone processors are notoriously inaccurate. Your installer could turn a dial on an amplifier to a setting labeled 80 Hz and end up with an actual crossover point of anything from 70 to 90 Hz.

Because digital signal processors use mathematical algorithms to alter the audio signal, they are incredibly accurate. Your installer can set a high-pass filter at 2,500 Hz for your tweeters and know that there won’t be any issues with power handling from unwanted midrange energy. The same applies to a low-pass filter at the top of the midrange driver. You don’t want any overlap or underlap (a gap in the frequency response) that could affect frequency response.

Taming Frequency Response Issues

To keep this discussion simple, let’s use a two-way bookshelf speaker on a desk as our reference for measurements. The speaker uses a 5¼-inch woofer with a glass fiber/foam core cone and a hard dome tweeter. Half of an eight-channel amplifier with integrated digital signal processing powers the speakers in a fully active configuration. This last statement means there is a pair of amplifier channels dedicated to the woofers and a second pair dedicated to the tweeters. No passive crossovers are used anywhere in the system. These speakers are used in conjunction with a dedicated subwoofer, so a high-pass filter has been applied at 80 Hz.

If we measure the frequency response of the woofer and tweeter with the mic close to their respective cones, we see the response curves shown in Graphs 1 and 2. You can see that the response of the woofer is relatively flat, with no significant peaks or dips at any frequency.

If we take a second measurement (Graph 2) of the entire system (both the woofer and tweeter playing at the same timer) at a distance of one foot from the speaker, we can see that the reflections from the desk and nearby objects have imposed peaks and valleys in the response curve. The deviation is more than 13 dB. These changes add emphasis to specific frequencies, changing the tonal balance of the speaker and detracting from the accuracy of the listening experience.

If we apply compensation using the equalizer built into the amp, you can see that the response at the listening position is smoothed. The natural balance of the audio signal is much more realistic at the listening position.

The interior of your vehicle imparts much more significant changes in response because of the abundance of glass, vinyl, plastic and carpet surfaces. Proper equalization is even more important in your car or truck in terms of achieving great audio performance.

Just as with our explanation for the need for accurate crossover settings, using a DSP will allow for precise amounts of equalization. If the system needs a cut of 2 dB at 1 kHz, 4 dB of boost at 320 Hz and 3 dB of cut at 80 Hz, the DSP can deliver with exacting precision and repeatability.

Pathlength Compensation

If the product specialist you’re working with is designing what’s known as a single-seat audio system, then they will want to adjust the output of each speaker in the car or truck so that the sound arrives at your ears at the same time. Compensating means adding delay to the signals going to the closest speakers. Processor calibrations that provide good imaging for both seats are also available, but use a different tuning process with no left-to-right signal delay

The result, when executed properly, is that the music you hear will seem to come from a point between all the speakers. In most cases, this puts the performance on what’s known as a virtual soundstage that spreads the width of the vehicle. If the equalization process was executed properly, each performer should be placed in their relative position across the stage. This phenomenon is called imaging.

Without compensating for pathlength, the soundstage will be clumped to the left side of the vehicle. This detracts from the realism of the performance. The closer you sit to the speakers in the door, the worse the image pulls to the left.

It should be noted that many people prefer to be immersed in the middle of their music experience. If you prefer a “club” sound, your installer can deliver that with the addition of rear speakers and a modified system calibration process.

System Presets

Many digital signal processors allow for quick access to presets. If your car is set up for a single-seat tune, your installer may create a second preset that removes the signal delay and changes the way the system is equalized. They may also create a preset that provides that immersive club-like sound. This type of calibration can be great if there are passengers in the rear of the vehicle who want to enjoy the music.

Depending on the processor, presets can be loaded using simple analog switches, with a dedicated remote control or with a computerized system controller. The selection method depends on the processor you and your product specialist agree to for your system.

Enjoy Great Sound from Your Car Stereo

If you have an existing aftermarket car audio system or are planning an upgrade in the near future, ask your local specialty mobile enhancement retailer about how adding a DSP and having it professionally calibrated can improve the performance of the system. Few upgrades offer a more dramatic and beneficial improvement to the realism and detail of a mobile audio 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.

One of the biggest upgrades you can make to a basic car audio system is to add a high-power amplifier. The most significant benefit of adding an amplifier is the ability for you to play your music at higher levels without running into distortion. Choosing the right amp for your car or truck is a tricky feat. There are thousands of amplifiers on the market, each with its own benefits and drawbacks. Let’s look at a few things to consider when shopping for a car audio amp.

How Many Amplifier Channels Do I Need?

The first consideration in buying a car audio amplifier is the number of channels you’ll need. Amplifiers come in everything from one to eight channels. Single-channel amplifiers are typically designed to power a subwoofer, while multichannel amps are great for actively filtered audio systems or upgrading modern premium audio systems. If you have a single set of 6×9 speakers on the rear parcel shelf on your Monte Carlo, then a two-channel amp will be perfect. If you want to deliver more power to the front and rear speakers in your Civic or pickup truck, then you will want to look at a four-channel amp.

You will want to consider future needs for your system when picking an amp. Thirty years ago, most amplifiers were two- or four-channel designs. Many systems used a four-channel amp to power a set of speakers in the front of the vehicle and the rear channels in a bridged configuration to drive a subwoofer.

These days, five- and six-channel amplifiers are quite popular. You can choose a five-channel amp to run the front and rear speakers along with a subwoofer and have complete control over the output of each set. As the popularity of fully active audio systems has increased, many five- and six-channel amps are running a subwoofer, a set of 6.5-inch midrange speakers and a set of tweeters. When configured properly, active audio systems sound amazing.

Amplifier Power Considerations

Picking the right amount of power is tricky. You can easily choose an amp that offers more power than you can use, especially for midrange speakers and tweeters. The trick is to choose one that will let you play the system loudly enough to meet your needs without distortion. If you shoot for a multichannel amp rated at 75 to 80 watts per channel, you should have enough for enthusiastic listening levels. If you are determined to keep the volume cranked to 11, then look for an amp in the 125 to 150 watts-per-channel range. You will, of course, need to make sure your speakers can handle that amount of power.

Choosing a subwoofer amp is a bit more complicated. These days, power is relatively inexpensive. A 600-watt subwoofer amplifier is more than enough for all but the most robust of subwoofers and should allow you to enjoy deep bass without running into distortion. If you are a bass-head, then consider something in the 1000- to 1500-watt range and upgrade to a pair of subwoofers to ensure that they can handle the heat created by all that power.

Amplifier Quality Determines Clarity

One thing that seems to get overlooked far too often is the quality of the amplifier people choose for their vehicles. We fully admit that navigating the thousands of options available is a daunting task. Let’s try to provide some insight about what specifications determine quality.

First and foremost, the specified frequency response can provide some insight. If you are looking at an amp rated at 20Hz to 20kHz with no deviation spec, well, that information verges on useless. If the spec includes a -1 dB tolerance, you know the amp should have no problem covering the entire audio spectrum with very little deviation. A tolerance of 0.3 dB is an ever better measurement spec. For something that may be better at reproducing your music, look for an even wider frequency range. A spec of 10 Hz to 50 kHz tells you that the designer has gone out of his or her way to create something special. Most DSP-equipped amplifiers are limited to 22 kHz on the top end.

Another telling factor in the quality and clarity of an amplifier is its signal-to-noise ratio specification. This measurement tells us just how much noise is added to the audio signal. Of course, less noise is better. The CTA-2006B standard, if followed (and it should be), specifies that noise measurements are taken at an output level of 1 watt when connected to a 4-ohm load. A mediocre amp will be in the -70 dB or higher range; a good amp would be -70 to -85 dB, and great amp would have a noise floor that is below -85 dB.

If you happen across a specification in the 100+ dB range, those measurements are taken at full power rather than at 1 watt. These numbers are not comparable. Look for the CTA-2006B spec when comparing numbers.

The real tell for the quality of an amplifier is its distortion specification. Sadly, most companies only provide something useless like <1% in association with a power spec. I can assure you that you won’t like the sound of an amp that adds 0.5% distortion to the audio signal. Ideally, amplifier manufacturers should provide a spec at the same 1-watt output level as the S/N ratio measurement. Anyways, what you need to know is that lower distortion is always better. You can most certainly hear the difference between amplifiers rated for 0.1, 0.01 and 0.001%.

Amplifier Features Add System Flexibility

You are going to want to pick an amplifier with a flexible input voltage range. 0.25 to 4V is good for most applications. Unless you have a digital signal processor, you will want an amp with electronic crossovers built in. It’s crucially important to the longevity and the performance of your speakers to ensure that they aren’t sent too much bass. Likewise, sending midrange information to a woofer sounds pretty bad.

If the amp you need will be used to power a subwoofer, then it should include a remote level control. Being able to fine-tune the sub for different types of music is, quite frankly, a lot of fun! We all know bass doesn’t have to be boring.

If you want to extract the best possible performance from your mobile sound system, look for an amplifier with an integrated digital signal processor. Providing your installer with the ability to add signal delay, accurate crossovers and equalization to your speakers is the biggest upgrade you can make to a car audio system. The acoustics of a car or truck are quite bad. Taming the peaks and valleys caused by reflections will restore the natural balance of your audio system.

Expert Installation Is Crucial

Once the product specialist at your local mobile enhancement retailer has helped you choose a high-quality amp for your system, you will want to have them install it for you. They have the tools and training to mount the amp securely, run all the power wire and signal cables carefully, and most importantly, configure the system to deliver great output with a minimum amount of background noise. After your new amplifier is installed, you can crank the volume and enjoy your music like you are front-row center at a concert without having to hear the system distort. Isn’t that what enjoying your music is all about?

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 car audio, what does being the best mean? Is the best amplifier one that makes the most power, adds the least noise, has the most features or is housed in a compact chassis that fits into your center console? Do the so-called best speakers produce a lot of bass or feature exotic materials? Does the best subwoofer play the lowest, or is it the one that’ll be the loudest? Describing something as the best is overused and imprecise. If you have even the vaguest understanding of electronics and the laws of physics, you might even see this adjective as a warning signal to keep looking.

We Want You to Have the Best

If you read any number of the hundreds of articles here at www.BestCarAudio.com, then it should be very clear that our focus is on premium products, world-class customer service and a desire to provide our readers with a genuine understanding of how mobile entertainment equipment works. We take pride in the research that goes into the content we create. It’s our goal to educate consumers about the products and services available for their vehicles.

If you spend any amount of time on social media, you’ll see manufacturers, distributors and retailers describe their car audio products and services as being the best. Describing something this way is an absolute statement. It is intended to imply that their solution is of the highest performance available. With more than 30 years of experience in the mobile enhancement industry, I can usually give you five reasons why their statement is invalid or, at least, incomplete. Does that mean the product can’t still be a great solution? No, it might be excellent. The question is, is it truly “the best”?

What Is the Best Car Audio Amplifier?

If you put a gun to my head and asked, “Dave, what is the best car audio amplifier?” I couldn’t give you a straight answer. Are you looking for the best sounding amplifier for subwoofers, for midrange drivers or one for SPL competitions? Does the amp need to be under a certain price point? Does the size of the amplifier matter? How many channels does it need to have? Is digital signal processing important? Do you care about after-sales support and a warranty?

I’ve had the fortunate opportunity to audition some of the most prestigious amplifiers ever created. Some of these amplifiers have five-digit price tags or have been calibrated by hand to reduce distortion at the expense of efficiency at low levels. Connected to my reference speakers in my lab, I know which of these would proudly serve as my benchmark, which ones offer exceptional performance for their price and which are nothing more than a feat of marketing nonsense housed in a fancy case.

I was talking with a friend last week who had just taken possession of an $8,400 four-channel amplifier for a client’s vehicle. After listening to the amp, he asked me how it could sound so much better than anything else he’d ever heard. I’ve dedicated a disproportionate amount of time to researching what separates one amp from another. The bottom line on this discussion was that the amplifier adds very little distortion or noise to the signal. In terms of competing products, this amp is likely an order of magnitude better than almost anything else currently available. Is it, therefore, the best amp available? Well, it isn’t if you are on a budget. It’s also huge, and that might pose a problem. With that said, it seems it’s pretty darned amazing.

What Are the Best Car Audio Speakers?

Another question that comes up time and time again is about the best speakers. Whether I’m browsing a high-end home audio group or reading questions and comments on Reddit (and shaking my head), I see people asking about the best speakers for their cars. I usually offer up a high-quality solution involving a three-way speaker set that runs about $2,400. I’ve heard a lot of speakers that cost a lot more, but they don’t play louder and all add more distortion to the signal than these. Sadly, the reply to my suggestion is that it’s too expensive. Weird; I thought they asked for the best.

While it seems that many in the mobile electronics industry don’t know this, the quality of a speaker is absolutely measurable. Its ability to handle power, how far the cone can move (and thus how loudly it will play), its mechanical and electrical linearity versus cone position, its efficiency and frequency response and how much distortion it adds to the signal are, or at least should be, part of the design process.

I often refer people to the JBL Synthesis website with a suggestion to read the development white paper on their innocent-looking 4367 Loudspeaker. If you can grasp the effort put into the design of the 15-inch woofer and the 3-inch compression driver, then you’ll quickly learn about what to look for when choosing speakers for your car, assuming you want the best.

Train Your Ears to Learn What is The Best

The last comment I’ll make before closing is about people who make statements like, “This is the best subwoofer I’ve ever heard.” In looking at the products associated with that sentiment, my first thought is typically, “Wow; you need to audition more subwoofers.” I’m not trying to be arrogant – that’s not my style. Not everyone is fortunate enough to have auditioned more than 100 different subs under very controlled conditions. I understand that completely.

Now, that person’s statement may be true, if you consider that they truly think it’s the best of all the subwoofers they’ve ever heard. Regardless, even with that taken into consideration, the usefulness of the statement remains questionable. Think of it this way: The first car you drive is the best car you have ever driven. What if that’s a Ford Tempo? (Sorry, bad flashbacks to the ’80s.)

If you want to choose the right audio products for your car, truck, boat or motorcycle, get out there and start auditioning. Go to shows and cruises and ask to listen to people’s systems. Learn what separates the good from the great in terms of performance and, most certainly, search through the hundreds of articles here at www.BestCarAudio.com to learn why you hear what you hear. As always, Happy Listening!
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.