• Skip to main content
  • Skip to primary sidebar
  • Skip to footer

Devine Concepts

Mobile Electronics Expert in Naples, Florida

  • Home
  • Services
    • Car Audio
    • Custom Installation
    • Driver Safety
    • Radar / Laser Detectors
  • About Us
    • Awards and Accolades
    • Meet the Team
    • Virtual Tour
  • Location
  • Contact Us
  • Facebook
  • Instagram
  • YouTube
  • Search

BestCarAudio.com

Product Spotlight: Rockford Fosgate T3S1-19 and T3S2-19 Superwoofers

BestCarAudio.com - February 12, 2024

Rockford Fosgate T3S1-19

When most people think of Rockford Fosgate, they remember that this brand has been delivering car audio products that enthusiasts have craved for over 50 years. Rockford Fosgate’s experience has made them a leader in the development of high-performance amplifiers, speakers and, of course, car audio subwoofers. Rockford has a truly incomparable solution for those who are truly fanatical about their bass. We’re talking about their flagship 19-inch Power Series T3S1-19 and T3S2-19 drivers. Let’s check them out.

Rockford Fosgate T3S1-19 and T3S2-19 Superwoofers

There are three series of subwoofers in the flagship Power Series. The T1 drivers are available in 10-, 12-, and 15-inch sizes. The T2 drivers start getting crazier with 13- and 16-inch diameters. At the top, we have the T3 19-inch drivers. To put that size into perspective, a typical 18-inch high-power subwoofer has an effective cone area of about 1,140 square centimeters. The T3 19-inch subwoofers have cones with a massive 1,472 square centimeter area. That’s an increase of 29%, which translates directly into an increase in efficiency and output.

Rockford Fosgate T3S1-19
The T3 19-inch superwoofers feature a cone made from two layers of glass fiber laminated on either side of an aramid fiber honeycomb core.

The T3 19-inch superwoofers are available in two models. The T3S1-19 has a single 1-ohm voice coil, while the T3S2-19 has a single 2-ohm coil. Speaking of voice coils, the aluminum voice coil former on these drivers has a diameter of 5 inches and includes a single edge-wound layer. Winding a flat wire around a cylinder on its edge isn’t easy to manufacture, but the single layer means no insulated air pockets of heat, as found on multi-layered coils. This means more thermal capacity, translating into more power handling and less thermal compression for improved overall efficiency.

The voice coil former is vented between the upper spider and the cone to release air pressure and heat at high excursion levels. Power ratings for the T3 19-inch drivers are 3,000 watts continuous with 6,000 watts as the peak. For daily duties, a single T2500-1bdCP is a great choice. Two T2500-1bdCP in PowerSync (strapped) mode will give you more than enough jam if you want to see who has the loudest system.

Keeping the massive 19-inch woofer cone under control is no easy feat, especially with linear excursion capabilities in the 2.7-inch range. As such, the chassis of the T3 woofers is very tall. The mounting depth is 15.62 inches. The chassis is a two-piece die-cast aluminum design with heat sink fins and extensive venting. The motor structure uses a dual-gap, multipole neodymium push/pull design with the voice coil having a dual winding design. A large neodymium magnet slug sits inside the voice coil and provides the electromotive force needed to move the cone. This geometry reduces inductance to numbers well below what some 10-inch woofers with 2-inch voice coils have. As such, the 19-inch woofers produce reasonable midbass – something many woofers today can’t claim at these power levels. As has been proven repeatedly, Rockford Fosgate doesn’t just do things big; it designs for sound quality and includes technologies that most other companies overlook to improve performance. Think of it like a Top Fuel Dragster combined with a Formula 1 car.

Rockford Fosgate T3S1-19
The T3S1-19 and T3S2-19 drivers stand almost 16 inches tall. This height allows for component placement that prevents cone rocking.

T3 Superwoofer Cone Assembly

The cones of the T3 superwoofers feature top and bottom layers of glass fiber that are laminated over a low-mass, high-strength aramid honeycomb core. This is the same construction used in aerospace applications. An aluminum dust cap ensures stability at high excursion levels.

The surround is made from injection-molded foam and uses Rockford Fosgate’s Vertical Attach Surround Technique (VAST) geometry to maximize the driver’s surface area. An aluminum clamping ring keeps the outer edge of the surround affixed to the chassis.

The Power Series T3 subwoofers use a pair of progressive Nomex spiders that are spaced several inches apart. This geometry is crucial to maintaining linear excursion at high power levels. Any rocking and the voice coil could make contact with the top plate. The tinsel leads from the voice coil are sewn to the upper spider to prevent noise and damage. Electrical connections to your amplifier(s) are made via a pair of massive spring-loaded terminals that can accept 4 AWG wiring. Just for some math fun, 6,000 watts into a 1-ohm load requires 77.4 amps of current continuously with peaks of over 92 amps. Yep, 4 AWG sounds about right.

Rockford Fosgate T3S1-19
A pair of Nomex spiders keeps the massive cone and voice coil assembly centered in the tight magnetic gap for improved efficiency.

Subwoofer Enclosure Simulations

By now, you should know that the Box Advisor tool on the Rockford Fosgate website is a valuable resource. We looked up the suggested enclosure for a T3S1-19 and were presented with a vented design with an internal volume of 8.0 cubic feet and a 69-square-inch vent that tunes the system to a ground-shaking 24 hertz. This would make a stunning subwoofer solution for a large home theater. In a van or SUV, it would be capable of scaring most audio enthusiasts. If you want maximum output for competitions, 6 cubic feet tuned to around 40 hertz will produce a nice peak where most vehicles are efficient. Based on the simulations, neither design has any power handling issues that are affected by excursion limitations above 20 Hz.

Rockford Fosgate doesn’t recommend a sealed enclosure for the T3S1-19 or T3S2-19, but it will work if you have 3.5 cubic feet of airspace. You’re probably better off with a 13-inch T2 in a vented enclosure. Unless, well, shock factor!

Rockford Fosgate T3S1-19
Predicted free-field frequency response and output of the Rockford Fosgate T3S1-19 in an 8-cubic-foot enclosure tuned to 24 hertz and driven with 3,000 watts.

Amazing Bass from the Rockford Fosgate T3S1-19 Superwoofers

If you have to have the biggest, baddest subwoofer on the streets, drop by a local authorized Rockford Fosgate retailer and ask about the mighty T3S1-19 and T3S2-19 superwoofers. You’ll need a well-constructed enclosure and lots of power to get the most out of one of these beasts, but the performance will be well worth the investment. For more information on the Power T3 superwoofers or any of the amazing car audio products from Rockford Fosgate, visit their website and follow them on Facebook, Instagram and YouTube.

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.

Filed Under: ARTICLES, PRODUCTS, RESOURCE LIBRARY Tagged With: Rockford Fosgate

Product Spotlight: Rockford Fosgate P3D2-10 and P3D4-10 Subwoofers

BestCarAudio.com - February 5, 2024

Rockford Fosgate P3D2-10

I can’t think of many name-brand car audio manufacturers offering more subwoofers than Rockford Fosgate. They have everything from affordable entry-level drivers with the Prime R2 series to competition-ready monsters in the Power series T3 Superwoofer. Near the middle of the pack are the impressive Punch P3 drivers that serve as the flagship of that series. Let’s take a close look at the P3D2-10 and P3D4-10 10-inch subwoofers.

Rockford Fosgate P3D2-10 and P3D4-10 Subwoofers

The P3-level 10-inch subwoofers in the Punch line are available in two voice coil configurations. The P3D2-10 has dual 2-ohm voice coils, which your installer can wire to be a 1- or 4-ohm load. The P3D4-10 has dual 4-ohm voice coils to be a 2- or 8-ohm driver. Many will wonder which is better. There is no better. The options exist to allow your installer to pick the right combination of voice coil impedance and driver quantity to optimize the power production capabilities of whatever amp you choose. Other than some minor variances because of the different mass of the voice coils, the two driver options are otherwise identical.

Rockford Fosgate P3D2-10
The Punch P3 subwoofers include an aluminum trim ring to conceal the mounting hardware.

Punch P3 Subwoofer Moving Parts

Let’s start by looking at the moving parts in the Rockford Fosgate P3D2-10 and P3D4-10 subwoofers. The drivers feature an anodized aluminum cone and dust cap. The cones are low in mass and rigid, and the aluminum helps extract heat from the voice coils wrapped around the anodized 2.5-inch aluminum voice coil former. A spun-laced Nomex reinforcement collar supports the joint between the former and the cone. Many overheated woofers fail at this joint, so this is a worthwhile upgrade in terms of longevity.

The tinsel leads from the voice coils are sewn to the oversized spider to ensure silent operation. At the top of the cone is a custom-tooled Santoprene rubber surround. The surround is bonded to the cone and then attached to the basket using Rockford Fosgate’s Vertical Attach Surround Technique, which optimizes the cone surface area. As a result, the P3 10-inch subwoofers have an effective radiating area (SD) of 360 square centimeters. Drivers rated similarly from competing brands are down at 345 or 327 square centimeters. When efficiency matters, so does cone area.

Rockford Fosgate P3D2-10
The VAST surround design increases the effective cone area to improve efficiency.

Basket and Magnet Assembly

The Punch P3 woofers have a unique deep-draw StampCast basket design. This basket design is stamped but looks like a cast basket, with to its geometry and crinkle-paint finish. The deep recesses on the sides of the four spokes add significant strength and rigidity to the design. Venting under the spider mounting plateau has also been included in the basket to improve power handling and make the driver more linear at high excursion levels.

The top edge of the basket features the FlexFit mounting slot design that allows for perfect alignment of the pad-printed artwork on the cone. The upper surface of the mounting lip is rubberized for a tidy appearance. A foam gasket is installed on the mounting surface to ensure an airtight seal to the enclosure. Finally, a machined aluminum trim ring gives the driver a tidy appearance and serves as the mount for the optional P2P3G-10 stamped mesh grille.

At the base of the basket is a massive magnet protected by a custom-tooled rubber boot. The pole piece includes a sizeable radiused vent in the center to relieve pressure under the dust cap and allow the inside of the voice coil to cool. Eight holes are drilled into the bottom plate to provide additional cooling under the voice coil.

Electrical connections are made by heavy-duty binding posts mounted at right angles to the basket. The wires enter the terminals from the bottom, keeping them out of the way when your installer is trying to load the driver into its enclosure.

Rockford Fosgate P3D2-10
The StampCast basket features a deep-draw design that provides excellent rigidity and strength.

Rockford Fosgate Punch P3D2-10 and P3D4-10 Specifications and Applications

In terms of specifications, Rockford Fosgate rates the P3 10-inch subwoofers as being capable of handling 500 watts continuously with peaks of 1,000 watts.

The drivers have a low-Q design, with the Qts being at 0.49 for the dual-two driver and 0.56 for the dual 4-ohm. The resonant frequency (Fs) is also low at 26.6 and 28 hertz, respectively. Finally, the equivalent compliance is relatively soft at 27 liters for either model. The Xmax specification is 15.2 millimeters for the D2 and 15.9 for the D4.

The Box Advisor tool on the Rockford Fosgate website suggests an acoustic suspension (sealed) enclosure volume of 0.59 cubic feet (net). This application results in a Qtc of 0.815 for the P3D2-10 driver with an F3 frequency that’s nice and low at 39.13 hertz. The suggested bass reflex (ported) enclosure has a net volume of 1.4 cubic feet with a vent tuned to 40 hertz. This enclosure, shown in red below, has an F3 frequency of 30 hertz and a nice bump centered around 45 Hz to give you a serious kick in the back. If you prefer a little rumble instead of boom, have your installer tune the enclosure to 32 hertz, and you’ll pick up about 6 dB of output at 25 hertz. None of the above enclosures have any power handling issues through the mid-band, though the vented enclosures would appreciate an infrasonic filter, as usual.

Rockford Fosgate P3D2-10
Predicted enclosure response: yellow, acoustic suspension; red, bass reflex.

Upgrade Your Car Stereo with Rockford Fosgate Punch Subwoofers

As two reviews on the Rockford Fosgate website note, these drivers are indeed little monsters. They have an impressive feature set that ensures reliability and linear performance. The electro-mechanical characteristics are optimized for impressive output, even from a small sealed enclosure. Finally, your installer can recommend any combination of Rockford Fosgate P3D2-10 or P3D4-10 subwoofers to optimize the output capabilities of almost any amplifier on the market.

If it’s time to add high-quality bass to your vehicle, drop by a local authorized Rockford Fosgate retailer and ask about the Punch P3 subwoofers. You can find a retailer using the locator tool on their website. Be sure to follow Rockford Fosgate on Facebook, Instagram and YouTube to learn about their new products and the amazing events they attend each year.

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.

Filed Under: ARTICLES, PRODUCTS, RESOURCE LIBRARY Tagged With: Rockford Fosgate

Differential Inputs are Your Friend

BestCarAudio.com - February 4, 2024

Differential InputsIn the 80s and 90s, it seemed like car audio installers were often having to resolve noise issues after installing a system that included an amplifier or signal processor. In many cases, the problem was called a ground loop. However, in some cases, the noise was present because one of the signal cables passed by a source of noise. The only solution was to reroute the wire. No matter what the problem was, or what cure was applied to resolve the problem, ultimately it wasted time and frustrated installers.

Noise problems are not as common these days. They do crop up from time to time, but certainly not with the same frequency as before. One simple technology that has helped to reduce noise issues is the inclusion of differential inputs of modern amplifiers and processors. In this article, we will explain what differential inputs are, how they work, and what benefits they offer.

Amplifier Input Circuitry – Single Ended Inputs

The RCA input connections on your amplifier have a relatively easy life. They do not need to pass any significant amount of current. They do not get connected and disconnect very often. They just sit there and do their thing.

Behind the connections, where the circuitry of the amplifier starts to do its job, there are two circuit designs commonly used. The aforementioned differential input, and single ended inputs.

In a single ended input design, the shield of the RCA cable is connected to ground through a resistor. This resistor is often around 1000 Ohms. The center pin of the RCA cable, which contains our audio signal, is connected to the preamp stage of the amplifier. The preamp stage includes the sensitivity control, crossovers and so forth.

The image below shows an RCA with a sine wave and noise on both the shield and the signal conductor.

Differential Inputs

When we feed the signal shown above into an amplifier with single-ended inputs, the noise on the ground wire is ignored, and the sine wave and noise on the signal wire are amplified. The unfortunate and unwanted result is below:

Differential Inputs

Amplifier Input Circuitry – Differential Inputs

In a device with a differential input design, the shield of the RCA cable is completely isolated from the chassis. Before the audio signal passes to the preamp stage of the amplifier, it goes through an op-amp. An op-amp (or operational amplifier) is a small IC that has two inputs and a single output. One input is labeled as +, and the other as -. When we put a signal on the + input, it is passed to the output of the device with little to no change. When we put a signal on the – input, the polarity of the signal is inverted and sent to the output. In a differential input configuration, the – input of the op-amp is also connected to the shield of the RCA.

If we have an audio signal on the + input, and nothing on the – connection, the audio signal is passed through to the output of the op-amp, then on to the pre-amp stage of our amplifier.

The image below shows an RCA with noise on the shield and the signal conductors.

Differential Inputs

If we have noise induced on the shield and signal conductor of the RCA, then the noise signal on the shield is inverted and passed to the output. The inverted noise signal adds to the non-inverted signal and cancels out.

Differential Inputs

We call the system a differential input because it is looking for the difference between the shield and the signal conductors. More accurately, it subtracts any signal that is common to both conductors from the output signal.

How does Noise get into the System?

When our interconnect cables run through the vehicle, they come close to all sorts of electrical noise devices. High-current wiring, computers, sensors, electric motors and even the alternator can produce radiated noise in the form of a pulsing magnetic field. When a conductor passes through this field, a current will be imposed on the wire.

When this imposed current (or signal) reaches our amplifier, it gets amplified. If the noise is a high-frequency buzz, then that buzz is amplified, and we hear it through our speakers. Yuck!

Another source of noise is a ground loop. In a ground loop, current is flowing on the shield of our interconnect to equalize the ground potential between two devices.

Differential InputsLet’s look at an example. Perhaps someone has installed a radio in the dash of a truck and grounded that radio to the dash support. In some cases, that dash support is isolated from the truck chassis with big rubber bushings. When we connect the RCA cables from our radio to an amplifier in the trunk that has single-ended inputs, the radio seeks an improved ground location through the RCA shield. The resistor in the amp prevents massive amounts of current from flowing, but there is often enough to induce noise in the signal conductor.

A quick test for a ground loop is to pull the RCA out of the amp until only the center pin is touching. If the noise goes away, you have a ground loop. A remedy is to install a ground loop isolator. A ground loop isolator is a device with a transformer in it. The audio signal is transferred through the magnetic interaction of the transformer windings. There is no direct electrical connection between the input and output cables. With no electrical connection present, current cannot flow. The drawback of a ground loop isolator is that it can detrimentally affect the frequency response of the signal passing through it.

Do the Interconnects Matter?

For differential inputs to work, we need the noise signal to be equal on both the signal and shield conductors of our RCA cables. In a coaxial cable design, the shield can block noise from getting to the center conductor. If you use coaxial interconnects with differential inputs, the noise on both conductors is not equal and can induce noise into the signal path.

Differential Inputs

The easiest way to ensure that any induced noise is equal on both conductors is to use a twisted pair interconnect. In a twisted pair configuration, both conductors have the same effective amount of shielding and subsequently, the same amount of noise.

Differential Inputs

Differential Inputs are Your Friend

The next time you are shopping for an amplifier or signal processor for your car, remember that one of the questions you should be asking is if it has differential inputs. While you can certainly build a great sounding audio system around an amp with single-ended inputs, there is no point of taking the risk of having noise or installation headaches. Your local mobile electronics specialist retailer would be happy to assist you in finding an amp or processor with differential inputs.

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.

Filed Under: ARTICLES, Car Audio, RESOURCE LIBRARY

Product Spotlight: Sony XS-162GS and XS-160GS 6.5-inch Speakers

BestCarAudio.com - January 29, 2024

Sony 6.5-inch

You’d think that the Sony product development team would deserve a break after releasing no less than nine new Mobile ES speakers and subwoofers over the past few years. While they might deserve it, they kept up the momentum by redesigning their popular GS-Series speakers. This Product Spotlight will examine Sony’s new XS-162GS component and XS-160GS coaxial 6.5-inch (16-cm) speakers.

Sony XS-162GS 6.5-inch Component Speakers

The XS-162GS is a 6.5-inch (16-cm) component speaker set that includes a pair of 6.5-inch (16-cm) woofers, two 13/16-inch (21-mm) soft dome tweeters, an inline passive crossover for the tweeter for discreet installation, and mounting hardware for the tweeters. The woofers in the set feature a high-quality stamped-steel chassis with a four-spoke design. The rigidity of the design is improved over typical stamped baskets by adding a reinforcing rib down the center of each spoke.

Sony 6.5-inch
The four spokes of the XS-162GS speaker basket feature a reinforcing rib for added strength.

The basket design includes two sets of mounting tabs, making it suitable for both three- and four-position mounting hardware when replacing a factory-installed speaker. The woofers have a total mounting depth of 1 7/8 inches and sit above the mounting surface by 7/16 inch. Your installer will need to leave extra room in front of the driver to ensure that the cone and surround don’t run into the speaker grille or a trim panel in your vehicle.

Sony 6.5-inch
Dimensions of the XS-162GS tweeters and woofers.

Each woofer is based around a composite polypropylene cone that delivers an excellent balance of bass and midrange frequencies. A foam rubber surround at the top edge of the cone features an air-filled matrix structure that’s low in mass while being durable. The result is a reliable and flexible connection that provides good damping characteristics.

The woofers in the XS-162GS set feature a phase plug design that’s a direct descendant of the Mobile ES XS-162ES speakers. The Dynamic Air Diffuser phase plug eliminates the need for a dust cap, which can add high-frequency distortion to the speaker. Further, the exposed ridges provide a significant amount of surface area to help extract heat from the voice coil and motor assembly. Sony uses a progressive-rate spider, another component brought over from the Mobile ES line, at the base of the cone to maximize physical power handling while providing precise compliance for accurate bass performance. A single ferrite magnet serves as the heart of each speaker.

Sony 6.5-inch
The Dynamic Air Diffuser phase plug improves power handling and reduces distortion for clearer sound.

The tweeters in the set feature a silk dome material with a diameter of 13/16 inch (21 millimeters). Each tweeter has a super-efficient neodymium magnet for excellent efficiency. The assembly is housed in a custom-tooled frame with a perforated mesh grille. Sony includes flush, angled and flat surface-mount accessories to optimize the installation. Filtering for the tweeter is handled by a passive crossover in line with the tweeter speaker wires.

Sony 6.5-inch
Sony includes flush, angled and flat surface-mounting hardware for the silk dome tweeters in the XS-162GS set.

The XS-162GS set has a continuous power rating of 45 watts that complies with the CTA-2031 measurement standard. Peak power is 250 watts. Efficiency is 89 dB at 1W/1M with a tolerance of 2 dB SPL. Finally, frequency response is specified as 45 Hz to 24 kHz using the IEC 60268-5 standard.

Sony XS-160GS 6.5-inch Coaxial Speakers

The sister speakers to the above are the XS-160GS 6.5-inch coaxial set. This speaker system includes a pair of two-way coaxial 6.5-inch (16-cm) speakers along with appropriate mounting fasteners. The basket design for the coaxial speakers is the same as those found on the component speaker woofers with seven mounting tabs. The woofer design is the same as the XS-162GS component speakers with a composite polypropylene woofer cone, foam rubber surround and progressive rate spider.

Sony 6.5-inch
The coaxial design of the XS-160GS is a direct descendant of the Mobile ES XS-160ES speakers.

Where the speakers differ is in the tweeters. The top of the Dynamic Air Diffuser post in the driver’s center is home to the 13/16-inch (21-mm) tweeter, with its integrated phase plug built into the mounting assembly. In both instances, the integrated phase plug, another trickle-down technology from the Mobile ES speakers, helps improve tweeter output around the crossover point. This improved midrange output allows Sony to lower the crossover point and reduce directivity issues typical in two-way systems that use a relatively large woofer. These tweeters share the same neodymium magnet design for excellent efficiency and compact dimensions.

All the specifications for the XS-160GS coaxial speakers mimic those of the component speakers with power handling rated at 45 watts continuous and 250 watts peak. Efficiency and frequency response numbers are also the same at 89 dB 1W/1M and 45 hertz to 24 kHz.

Sony 6.5-inch

Environmentally Friendly Packaging

Sony has committed to significantly reducing environmental impact by simplifying the packaging design for the GS speakers. Gone are the fancy full-color graphics, now replaced with single-color line art, reducing the amount of ink by about 90%. The internal packaging is now paper-based, further reducing environmental impact.

Great Sound with a Great Warranty

Sony backs the XS-162GS and XS-160GS speakers with a three-year warranty that covers defects in materials or workmanship during ordinary consumer use. As with all speakers, you’re on your own if you overpower them with a large amplifier or too much distortion and damage them.

We have each set on their way to our labs for a Test Drive Review, so we can share how they perform shortly. In the meantime, if you want a great set of speakers to connect to a factory-installed or aftermarket radio, drop by a local authorized Sony retailer and ask for a demonstration of the new 6.5-inch (16-cm) GS series speakers. You can find an authorized Sony car audio retailer using their dealer locator. For more information about Sony Car Audio products, follow them on Facebook.

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.

Filed Under: ARTICLES, PRODUCTS, RESOURCE LIBRARY Tagged With: Sony

Bench Battle: Headunit Features vs. Performance

BestCarAudio.com - January 7, 2024

Headunit FeaturesAwhile ago, a client asked us what you get when you buy a “better” headunit. The usual answer is that you get more features and improved functionality. Those of us with a drive for the ultimate in sound quality and realism from our mobile electronics systems choose products in hopes of them receiving improved sound quality. Beyond frequency response and noise, what else makes one radio sound better than another?

We invited two head unit specimens to the Best Car Audio test bench for a little head-to-head battle. The first subject is a modern multimedia station that is equipped with navigation, smartphone integration and the general Bluetooth goodness. The challenger is a veteran, but premium, CD receiver. It has never heard of MP3 files, doesn’t understand the concept of satellite radio and thinks Bluetooth is the result of eating blueberry pie. However, in its day, it was one of the best. We do not need to mention names here, but we will call this the bench battle of features versus performance.

The Equalizer – Premium Test Equipment

Measuring the frequency response of a car audio product is relatively easy if you can feed a known signal into the device. When it comes to measuring a signal source, that is responsible for generating the signal, so all we can do is measure the output. We have a high-end digital interface on our bench. It offers a flat frequency response from 5 Hz to 92 kHz with a tolerance of 1 dB. The signal to noise ratio is an amazing 116 dBA and distortion is specified at less than 0.00032%. These specifications exceed those of both source units we are going to test.

Frequency Response Measurement

Testing the frequency response of a source unit requires some trickery. We have developed a reliable method that has proven itself time after time. The image below shows the frequency response of the reference signal. It has a slight incline in the high-frequency region, but everything is within a tolerance of about 1 dB. We converted this 192 kHz, 24-bit test track down to the CD standard of 44.1 kHz and 16 bit. Response to 22.05 kHz remains ruler-flat.

Headunit Features
Reference White Noise Signal

Frequency Response Results

Before we get into the results, we want to explain how to use the measurement graphs. The test track uses random noise as part of the test procedure. We process that after the test is complete. What you want to observe is the trend of the charts. A small peak or valley is not an anomaly in this scenario. Average the curve in your mind to see the overall trend.

The CD receiver: We played our test track from a standard CD audio file to make sure both source units were given the same information. The frequency response of the unit showed a typical response. The high-frequency filter kicks in around 17 kHz, which is normal for consumer products.

The DVD receiver: We played the same CD in the DVD receiver to see how it responded. The manufacturer of the DVD receiver has included a 2 dB boost on the top end that starts at 7 kHz and peaks at just over 2 dB at 15 kHz. The high-frequency filter response is similar to that of the CD player.

The high-frequency boost is not a big deal in terms of how a system sounds. Most of us have some high-frequency attenuation in our hearing, so this helps put some of the sizzle and air back into our music. It would be worth checking whether the source unit output clips when a 0 dB 15 kHz tone is played. This article is not a product review, so we will save that for someone else to tackle.

Headunit Features
Frequency Response Comparison

Bring the Noise

Our next challenge for the new versus old shootout is a little more technical: We wanted to see how each unit performed regarding background noise. This test is often reserved for lab environments, but can quantify the effort put into the component selection and system design.

For this test, we used a 1 kHz test tone recorded at -90 dB relative to full scale. Because the two source units have different pre-amp capabilities, we adjusted them so the output of the 1 kHz tone was equal in amplitude. This would best depict the noise imposed on the signal.

Headunit Features
1khz Noise Test

The CD receiver: We can see that the background noise relative to the signal is very quiet. There is a little bump at 60 Hz that was created by the power supply on our test bench. Otherwise, the test was impressive.

The DVD receiver: The background noise relative to the 1 kHz is 10 to 15 dB louder than that of the CD receiver at higher frequencies. There are also some spurious harmonic distortions in the output signal, mostly above 1 kHz. The large bump in noise in the low-frequency region could be caused by our 60 Hz 120 volt power supply causing some harmonics. The bandwidth is really wide, so it is hard to determine for sure.

A Distorted Perspective

We decided to repeat the test with a full-amplitude 1 kHz sine wave to see what harmonic content would be created at higher internal levels. The limits of the FFT analysis in our software starts to show up here. The flat horizontal line on the left of the chart and the angled line on the right are due to the analysis software and don’t represent noise.

Headunit Features
1kHz Noise Test 0dB

The CD receiver: We noted two small harmonics at 14,750 and 165,000 Hz, with a slight harmonic at 12,000 Hz. Otherwise, the signal was very pure.

The DVD receiver: Harmonic distortion was clearly present at 1 kHz intervals starting at 2 kHz. It is worth noting that the first resonance is 45 dB quieter than the reference signal. If you were just playing the test tone, you might be able to hear it, but only just barely.

The Grand Finale – Intermodulation Distortion

Testing for intermodulation distortion is, well, mean. Out intermodulation distortion test is comprised of a CD test tone with 19 and 20 kHz sine waves played simultaneously. The spectral response of the test track can be seen below.

Headunit Features
Intermodulation Reference

The CD receiver: When you are looking at an intermodulation comparison test, you are looking for frequency content that wasn’t in the original file. In the case of the CD receiver, we can see a very small bump at 1 kHz. This is significant because it is the difference between 19 kHz and 20 kHz. This would be considered an excellent result. A few other spikes show up at 3,500, 4,500 and 9,500 Hz, but they are still quite low – peaking at -93 dB relative to the test signal level of –15 dB.

The DVD receiver: We cannot really explain what happened here. There is 1 kHz content only 20 dB down from the 19k Hz and 20 kHz tones. Then harmonics upon harmonics of this up to 21 kHz. This test shows why some source units sound accurate and pure, while others do not.

Headunit Features
Intermodulation Comparison

Are Headunit Features Worth the Trade-off?

A few months ago, we published an article about harmonic distortion. That served to establish the basic understanding of how distortion creates content that wasn’t present in an original audio file. Our intent in this comparison is not to put down the modern DVD receiver, but to show what happens when manufacturers forego the bells and whistles and simply focus on all-out performance.

The same tests that apply to these source units are also common in amplifiers and speakers. We will subject an amplifier to the same mean and nasty tests in the coming months.

Don’t ever let price, perception or age dictate how you think a product sounds. Work with your mobile electronics specialist retailer to listen and compare for yourself. You will be amazed at what you hear.

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.

Filed Under: ARTICLES, Car Audio, RESOURCE LIBRARY

  • « Go to Previous Page
  • Page 1
  • Interim pages omitted …
  • Page 8
  • Page 9
  • Page 10
  • Page 11
  • Page 12
  • Interim pages omitted …
  • Page 33
  • Go to Next Page »

Primary Sidebar

About Us

About Us

Devine Concepts is a mobile electronics retailer based in Naples, Florida. We are led by Adam Devine, a 20-year veteran in the industry and a Mobile Electronics Association top 50 … [Read More...]

Take a Tour of Our Facility

virtual tour

We invite you to tour our facility virtually. We hope you love what you see. (It’s even better in person!)

Car Audio

Car Audio

Devine Concepts in Naples, Florida, specializes in car audio. While some shops offer this as one of their services, it is the main focus in our facility. In fact, our owner Adam … [Read More...]

Radar / Laser Detectors

Radar / Laser Detectors

One of the specialties at Devine Concepts in Naples, Florida, is laser and radar detectors. We offer both portable and custom-installed solutions to our clients. It is our opinion … [Read More...]

Custom Installation

Custom Installation

Custom Installation

Devine Concepts in Naples, Florida, was founded in 2018 by Adam Devine, an MECP Master Installer with more than 20 years of experience,  and one of the most-awarded mobile … [Read More...]

Footer

Location


Get Directions to Devine Concepts

Address

Devine Concepts
14848 Old 41 Rd
Suite 9,
Naples, FL 34110
Phone: (239) 451-3210

Services

  • Car Audio
  • Custom Installation
  • Driver Safety
  • Radar / Laser Detectors

Connect with Us

  • Facebook
  • Instagram
  • YouTube

Store Hours

SundayClosed
Monday9:00 AM - 5:00 PM
Tuesday9:00 AM - 5:00 PM
Wednesday9:00 AM - 5:00 PM
Thursday9:00 AM - 5:00 PM
Friday9:00 AM - 5:00 PM
SaturdayClosed

Copyright © 2025 Devine Concepts · Privacy Policy · Website by 1sixty8 media, inc. · Log in