Tag: amplifiers

How to Tune an Amplifier


In order to get the absolute best performance & sound quality from your amplifier it is very important to know exactly how to properly tune an amplifier. The most common misconception of tuning an amplifier is that the settings are intended to ‘give you the most power output’, this is not the case. This article will break down exactly what each common setting on an amplifier does and how to properly tune those settings.

For this example we are going to use the DC Audio 7.5k as an example. Onboard, it has the most common settings found throughout the market. The names might be a bit different, but they do the exact same thing, more on that later. Moreover, this article will cover each setting Right to Left – use the picture below to follow along – ending at the Gain, which is easily the most important setting of them all.
DC Audio 7.5k

  • Master/Slave Switch

  • The Master/Slave Switch is ONLY ever used when “Strapping” the amp with another identical-twin amp (i.e. Same Series, Model, etc..). Stay tuned for a future article on how this is done, But for this explanation we are assuming ONE amplifier one, so this switch must stay on MASTER. What does “Slave” do? Stay tuned for the explanation on “Strapping”.

  • Phase

  • Inverted Subwoofer
    The job of the phase setting is to do one thing: change the polarity/direction of the sub(s) being ran off the amp. The most common reason why you would want to use this setting is when you have an ‘inverted’ subwoofer*. You could, however, just as easily swap the polarities of each terminal and accomplish the same thing. Another reason why you would use the setting is if you have two drivers & two amps (one per driver), and one is “Out of Phase”. This means ONE driver is playing OUTWARD (away from the enclosure) and the ‘Out of Phase’ driver is playing INWARD (into the enclosure). What happens in this case is , in theory, the two sound waves coming off the driver cancel/eliminate each other, giving a very undesirable result. So when you hear someone say the driver is “out of phase” THIS is the go-to setting to try to fix that. Beyond that, rarely can an audible change be actually heard, but there are more variables beyond just the setting that will make a change.

    For our example, we assume the driver is wired properly, so this is left at 0

    *Inverted Subwoofers are often done for one of two reasons:

    1. To utilize the absolute most volume of the enclosure. Without a subwoofer displacing the air within the enclosure you have FULL use of that space.
    2. Because it looks cool. Yes, really.
  • LPF

  • Low Pass Filter.The LPF can be thought of as a “Ceiling”. The LPF will not allow the frequencies above where you set it to pass through. Technically speaking, there is a “Roll Off”, the LPF isn’t just a ‘wall’, but we won’t get into that here. The setting is intended to ‘filter out’ frequencies that which the driver – in this case a subwoofer – cannot play and/or will harm the driver if it does so. There isn’t a “right way” to set this, there is only the way the setup is configured and also what the limitations of the driver are.

    Suggestion: The most common (read: ‘dummy proof’) setting is 80Hz-120Hz

    Consider this, however, if the Full Range stage of your setup (i.e. Door Speakers) for some reason are incapable of playing below 120Hz , then you want the subwoofer to pick up at 120Hz; so the LPF will be set at 120Hz! This is because you wouldn’t want your sub Playing 80Hz and Down, then your Full Range Playing 120Hz and Up, because then you will have an inaudible gap between 80Hz-120Hz (i.e. Dead Space). For all intents and purposes we suggest to stick 80Hz; this will make sure all ‘mid-range’ is filtered out, and its often the most easily recognizable crossover point. Unfortunately, Most Amps do not tell you where a specific crossover point is , so you definitely need to ‘Eye Ball’ it. An overlap of frequencies – Sub vs Full Range – isn’t a “bad thing”, but for those who want the “Perfect Setup” you will have to have the right tools to hit the points you want. The only way of doing this is with the use of a Crossover Calibrator; we use the SMD CC-1 in our installation department to hit these points accurately.

  • Bass Boost

  • The Bass Boost is fairly self explanatory. It literally boosts the frequencies that you send it. We DO NOT recommend using this setting, if at all possible, because drivers go here to die. Assuming the amp is tuned right, there is seldom a reason to come to this setting. The reason it exists is because:

      1. Manufacture’s need to compete with another, so if multiple amps have this setting, then theirs does too
      2. It can actually have a practical use

    The latter only ever happens when the Full Range completely over powers – or “Drowns Out” – the subwoofers’ outputs. In order to “balance” the setup, you go to the Bass Boost to give the output a bit more output. THIS ISN’T A VOLUME KNOB!! You are toying with introducing a distorted signal if this setting isn’t used responsibly. Use at your own risk.

    Suggestion: Leave at 0

  • Subsonic

  • For all intents and purposes think of the Subsonic as a HPF (High Pass Filter), the ‘opposite’ of the LPF, or as a “Floor”. The Subsonic will not allow the frequencies below where you set it to pass through. Like the LPF, this setting is intended to ‘filter out’ frequencies that which the driver – in this case a subwoofer – cannot play and/or will harm the driver if it does so. This setting is often established by the limitations of the driver. For example, the NVX VCW104 has a frequency response of 20Hz-220 Hz, which means it is physically incapable of playing below 20Hz. This tells us that if we want to protect the driver, we should set the subsonic to 20Hz. Many in the industry will say that the ideal setting, for this example, would be ~25Hz because “just because its capable of doing 20Hz doesn’t mean it Should”. The often cited analogy is “your car Redlines at ~7,000 RPMs, that doesn’t necessarily mean you SHOULD ride the engine at 7k just because it can”. Nevertheless, in a properly tuned setup, and with an able/responsible user, there is very little concern for setting this point to the limitation presented by the driver.

    Suggestion: Set to 20Hz , for most subwoofers

  • Gain

  • This is NOT a volume control!! Whatever you want to call this setting, it is intended to do One thing and that is to match the sensitivity of the source/headunit. So, in theory, if your headunit provides a solid 5v out of the preouts, then the Gain (Sensitivity, Level, Input Level, Sensitivity Input, (V)) will match that when set properly. Due to several variables it is more likely that it is not going to match EXACTLY (i.e. at 5v) but it will come fairly close. Unfortunately, without special tools or an oscilloscope it is very hard to get this “Right”. It isn’t impossible to set this without special tools however. In fact, most installer set up their customers’ amps by ear! This will be the most common method you – the reader – will use. In addition, there is also a creative way of using a common DMM (Digital Multimeter) & Ohm’s Law to establish an AC Voltage Figure to aim for when adjusting the Gain; a quick search for this method will generate a lot of useful information. However, it is important to know that using the DMM method ASSUMES that the figures/variables you use are SPOT ON , which – to be fair – is not likely. This is because the rated figures on an amp are often rounded up/down, and – worse – a lot of manufactures will give overrated figures. So, using this method can be precarious if you the figures aren’t True To Spec.

    Suggestion: Too many variables to provide a “right answer”

    To Recap:
    Master/Slave – Master (Assuming ONE Amp)
    Phase – 0
    LPF – 80Hz
    Bass Boost – 0
    Subsonic – 20Hz
    Gain – ____
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    What is a Bluetooth Amplifier


    One of the best perks of constantly evolving technology is the new products that hit the market every year. While Bluetooth amplifiers aren’t technically new, RE Audio released the BT900.4 Bluetooth amp about a year ago, they are becoming increasingly more common with Cerwin Vega, Infinity, JBL and Kicker releasing their own Bluetooth amps with more sure to hit the market soon.

    If you drive an older car, chances are you probably don’t have Bluetooth. A Bluetooth amp is perfect for you if you aren’t interested in taking out your factory stereo to add an aftermarket stereo with Bluetooth. Not only will you add Bluetooth to your vehicle, you’ll be able to amplify your speakers and improve the overall performance of your system.

    Why You Want One

    • Stream Music Through Your System Directly from Your Amplifier
    • Eliminate the Need of an Expensive Head Unit
    • Amplify Your System

    How Bluetooth Amplifiers Works

    Bluetooth Amplifier Diagram

    A Bluetooth amplifier is actually a pretty basic piece of equipment. It functions and installs just like any other amplifier would (they can be connected to a source unit, but it isn’t required), it just has an integrated Bluetooth module installed in it allowing you to connect virtually any Bluetooth enabled device (smartphones, tablets, etc.) to it wirelessly. Bluetooth amps eliminate the need of a traditional head unit because they allow the amp to double as the receiver.

    Kicker PXiBT50.2

    Common Applications

    One of the things that makes a Bluetooth amplifier great is the flexibility it provides you with. While a Bluetooth amplifier will make an excellent addition your car’s sound system, they are also a perfect fit for marine and power sports use, as well as just about any other application that requires an amplifier.

    In the Car

    A Bluetooth amplifier adds another, and perhaps the most efficient way to add Bluetooth to your car. Many older stereos don’t have built-in Bluetooth simply because it wasn’t a common feature. Until the release of Bluetooth amplifiers the only way to add Bluetooth to your vehicle was through a new, potentially costly, Bluetooth headunit or a Bluetooth adapter that was compatible with your stereo. With a Bluetooth amp you can knock out two birds with one stone. You’ll add the convenience of wireless Bluetooth streaming to your car while also amplifying your existing system. Some Bluetooth amps also include a wired microphone, enabling hands-free phone calls.

    On the Boat

    Bluetooth amplifiers aren’t just for use in your car, they’re also a great for streaming music out on the lake. Many boats don’t even have a sound system installed, so if you want to add a system you’re probably going to need to build it from the ground up. A marine rated Bluetooth amplifier allows you to skip over a head unit all together, saving you money while improving the performance of the rest of the system. And much like in your car if your boat does have a sound system and the head unit isn’t Bluetooth enabled, a Bluetooth amplifier can save you from having to change out the stereo.

    On the ATV

    For anyone interested in outdoor power sports, you know that free space is incredibly limited. Installing a sound system in an ATV, UTV, SSV or motorcycle can be a tricky proposition because of this and anything you can do to save space can be invaluable. A Bluetooth amp can consolidate your source unit and amplifier into one piece of equipment without sacrificing the ability to actually play music through your system.

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    Car Audio 101: Car Amplifiers

    An amplifier is really a simple piece of your aftermarket sound system. A car amplifier basically amplifies a signal from a source (in the case of a car sound system, your stereo) to a much greater signal. Signals from source units are typically fairly low voltage, which is fine for most speakers (but not subwoofers), amplifying your speakers will make them perform to their full potential. Now, your speakers can be powered by just your source unit, but a subwoofer will require an amplifier. Giving your system more power will improve both sound quality and how loud your system will play.

    When looking for an amplifier, it’s important to know what you intend to use it for. If you’re simply adding a subwoofer to your system you will only need a monoblock amp while with a complete system (4 speakers and a subwoofer) your best bet is either a 4 channel and a monoblock or a 5 channel amplifier. It is critical to the success of your sound system that you match up all of your equipment (speakers, subwoofer, source unit) with the right amplifier to make sure everything is powered properly to give you the best sound possible.

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    More Car Audio 101


    CEA-2006 Compliant Amplifiers

    CEA Rated Audio Components are a Sure Thing

    All CEA-2006 compliant amplifiers are tested using the same specifications so you can easily compare any CEA compliant amplifier. The old Consumer Electronics Association power amplifier rating system standard, the EIA 517B, was lax in its ways and allowed car audio manufactures to rate their amplifiers power output almost any way they choose, so long as it was listed. Thus trying to compare amplifiers was an apples-to-oranges ordeal.

    To make the amplifier comparison process easier for everyone to understand, any amplifier stamped with the CEA-2006 product mark can be compared evenly to other amplifiers with the same mark. This allows for an apples-to-apples comparison of all amplifiers which contain the CEA logo. Amplifiers are rated primarily by their Output Power and Signal-to-Noise Ratio which must appear in conjunction with the CEA-2006 logo on the product packaging.

    CEA-2006 Compliant Standard

    CEA-2006 Compliant Standard- Listed Amplifiers

    Manufacturers are required to:

    • Express output power as watts RMS
    • Measure with 14.4V DC supply
    • Utilize testing under a 4-ohm load
    • Have 1% or less total harmonic distortion in the amplifier’s output.

    The Signal-to-Noise ratio of an amplifier is how much extra noise is present in the amplifiers output signal compared to the signal being fed to it by a source. Basically, it’s the amount of “hiss”, “crackling” or “popping” you hear when your music is quiet or there is no music playing. CEA requires that this noise is compared to an output signal at 1 watt. Other amplifier specifications have been standardized for an equitable comparison. Many manufacturers are already using the CEA-2006 rating method and the list keeps growing, so be on the lookout for the CEA logo the next time you purchase an amplifier.

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    How to Tune and Adjust Amplifier Gains and Bass Boost


    You might want to force this into your head because tuning your equipment is one of the most important things you can do. Car amplifiers have lots of knobs and buttons that, when adjusted the right way, will make your subwoofers or speakers perform at their best. Improper tuning can create distortion, which can sound like buzzing, crackling, hissing, whomping, and various other noises that intrude on the instruments of your music. This is a ballpark method for setting up an amplifier, always refer to the owner’s manual first for more detailed and specific instructions. Most of us do not have an oscilloscope to properly tune a system, but the method outlined below will work well enough. Now let’s get down to tuning!

    Kicker IX500.4

    4-Channel Class D Amplifier- Kicker IX500.4
    Step 1: Setting Volume and Gain Control

    With your sound system off, disconnect the RCA cables that run to your amplifiers. Next, turn your system back on and turn the volume on your radio up to max, make sure no music is playing in the system. Disconnecting the RCAs makes sure nothing is playing through the amplifiers which would risk blowing your amplifier, speakers, subwoofers and eardrums. If your speakers run off of your radio and you have a subwoofer amplifier that your trying to set, disconnect all your speakers for safety, then reconnect them after you find the 75% volume level highlighted below. You can leave the speakers connected only if you are 100% sure no music is playing through your system. Most radios have a numerical association, for example the max volume could be denoted as “60” on the dial. The numbers for each radio differ; some might be at 10 max while others could be at 30 or even 100 max. Now that you have the max volume number, multiply it by .75, this will get you 75% of your max volume. For example, if our max volume is 60, then 0.75 x 60 = 45. Now that we have that figured out, turn your volume to zero and plug in your RCA cables or speakers if your running off the headunit. Now, turn the volume down to the 75% point (45 in this case) and turn the gain on your amplifier to zero. Set all bass boost and crossover filters to off, and make sure your headunits built-in EQ is set to “Flat”.

    We recommend you use a 1-kHz sine wave tone from a test disc for this next step. If you cannot get a test disk purchase a store bought CD with your favorite music and use it instead. With your sound system off, plug in your speakers if you disconnected them and RCA cables and then turn your system back on. Now start playing the tone, slowly turn the gain up on the amplifier until you hear distortion, also known as clipping. Back off the gain about 1/8th a turn or until it becomes clear again. Remember to mark the gain level and the volume level should you need to reset them at a later date. This is the maximum volume your system will play before it might start clipping the signal. If you have multiple amplifiers, use this method for each amplifier separately. So, hook up only one amplifier at a time, unhook it and move on to the next one.

    AutoSound 2000 CD-104

    Amplifier Level Setting CD- AutoSound 2000 CD-104
    Step 2: Tuning Frequencies

    Time to adjust the built-in crossovers on the amplifiers in your system. Most subwoofer amplifiers have a Low-Pass Filter which prevents higher frequencies from reaching your subs. Subwoofers are designed to reproduce low frequency bass tones, so a low-pass filter is very important. A great starting point is around 80 to 100Hz on the low-pass crossover. Disconnect all other amplifiers and play your favorite music type from a CD at 75% volume. While listening to what the subwoofer is playing, slowly adjust the low pass filter from high to low until the mid-frequencies and high-frequencies disappear. You need to filter out cymbals, vocals, guitars, strings, and any other instruments that are not bass or low drum type. If you experience any popping or muddy sounding music from the subwoofer, turn the filter down lower.

    For your speaker amplifier, you will have a Low-Pass and a High-Pass filter set on a switch so you can choose which to use. The High-Pass filter lets all frequencies above the setting to go through to your speakers while preventing the lower bass notes from getting through. Disconnect all other amplifiers and start playing your favorite music from a store bought CD. Your subwoofer will handle the lower notes, so a great place to start on the high-pass filter is where you set your low-pass filter on your subwoofer amplifier if you are using one. If not, a good starting place is between 60 and 80Hz. Listen to your speakers as you adjust the high-pass filter slowly. Get rid of any bass or low drum kicks that might cause distortion in your speakers.

    Step 3: Bass Boost

    If your subwoofer has a death wish, this is often the way to grant that wish. Bass boost can be very effective but it is rarely ever set correctly. The objective of the bass boost, should you want to use it, is to get more kick out of your subwoofer. For most, the bass boost is best left untouched, but you’re not most are you? Ok, so set your gain to zero, and toggle your bass boost button, switch, or turn dial. Play your favorite music and slowly turn the gain up until you get distortion. Back off the gain setting until the woofer is clear again, then start adjusting the low-pass filter. You will need to mess with the low pass and gain until you feel your woofer sounds just right. Bottom line; if you’re going to turn the bass boost up, make sure to turn the gain down. Bass Boost is not a toy and must be used responsibly.

    Step 4: Mix it All Together

    Kicker IX500.4

    Speaker Polarity Checker- PAC TLPTG2
    Phew, final step! Let’s connect all amplifiers in the system, turn the radio down to zero and start playing that CD. Slowly turn the radio up until you hear distortion or you reach that 75% limit, do not ever go past that limit. If everything was done correctly, all speakers and subwoofers should be distortion free until that point. If the bass is overpowering the speakers at the 75% volume point, lower the gain on your subwoofer amplifier until it blends well with your speakers. Do not adjust the full-range speaker amplifier to match the subwoofer(s). If your bass is not sufficient enough for your needs, you will need to upgrade to a bigger subwoofer and a more powerful amplifier.

    If you can’t seem to get your system to sound just right, we highly recommend you take it to a professional. It is possible your components could be damaged, connected improperly, or simply not efficient or of enough quality to produce the sound you need. Simple things such as replacing power, ground, and speaker wire with higher quality cable could help improve the sound of your system. It is also possible that the polarity on your speakers could be switched, resulting in awkward sound reproduction. A polarity checker can fix that issue quickly. If you listen to a wide range of music, try readjusting your gain controls using different CDs with different music types to get the most even sound. Tuning is all about hearing the difference.


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    What Types of Wiring Do I Need to Install an Amplifier?


    Power wire…ground wire…everything seems to involve wires. There is no escaping it, your amplifier needs wires or it won’t provide you with high quality sound. To make sure you have everything your amplifier needs, I am going to give you a brief overview of all the necessary wires that the average amplifier uses. To make the process simple, many manufactures offer complete amplifier installation kits which come with everything you need.

    Kicker 09ZCK4

    Complete 2-Channel Amplifier Installation Kit 

    Power and Ground Wires: The job of an amplifier is to amplify a signal from the radio or source unit. However, without sufficient power to do so, the amplifier is non-effective. A proper power and ground wire are required to provide current to any amplifier. A 4 gauge cable is the standard size for most amplifiers, however other sizes exist. The ground wire gauge must be the same as the power wire, and no more than 3ft from the amplifier. For more information on this, see our article on Power and Ground Cable.

    Speaker Wire: Whether you are wiring up subwoofers or speakers, speaker wire is used to make the connection. A monoblock amplifier will have 2 to 4 speaker terminals to make the connection to your subwoofers. A 2-channel will have 4 input terminals and a 4-channel will have 8 terminals.

    RCA Cables: Amplifiers need an input signal to provide the musical data for the amp to output to the speakers. RCA cables are commonly used to carry audio or video signals from one device to another. A single cable is used for each channel on the amplifier, and they come in pairs of 2. A 2-channel amplifier will use a one pair RCA cable, and a 4-channel amplifier will use 2 pair RCA cable, etc..

    Remote Turn-on Wire: Just connecting power and ground to an amplifier is not enough. The remote turn on lead wire is responsible for telling the amplifier to turn on when the vehicle or accessory power is activated. This wire connects to the blue-white turn on wire or blue power antenna on the wiring harness of most aftermarket receivers.

    Speaker Level Inputs: Some amplifiers come with speaker level inputs, most commonly found on 4-channel speaker amplifiers. Speaker level inputs are used in place of RCA cables to provide a signal input to the amplifier using speaker wire connected to your actual speakers. This method is most commonly found on systems where the owner does not wish to replace the OEM radio.

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    How to Match a Subwoofer and an Amplifier

    As you scavenge deeper into the realm of car audio, you begin to realize that figuring out the proper amplifier/subwoofer setup is a lot harder than just matching power ratings. As you sift through all of the different manufacturers, you might notice that the word “ohms” appears often.  Have you found yourself wondering, “Well the subwoofer is 2 ohms, so I should probably get an amplifier at 2 ohms?” In most cases you would be incorrect, for various reasons. To avoid confusion, we’ll let scientists deal with Ohm’s Law and instead focus on the actual matching process. In this article I will explain to you how to match a subwoofer and amplifier so you do not end up blowing any fuses, mentally or physically.

    There are a few criteria we have to look at first. For example, the distinction between a monoblock amplifier and a 2-channel amplifier, as well as the difference of a single voice coil subwoofer versus a dual voice coil subwoofer. I will discuss these categorically and explain each one, so when it is all said and done, you just have to match up your equipment in a chart to find the answer! Let’s start with some terminology:


    This does not refer to the channels that you switch between on your TV while trying to find the Lakers game, and it does not refer to a channel that is filled with water. In the audio world, the word “channel” refers to the stream of data on one line, or in the case of amplifiers, one cable of power. A single channel amplifier has one terminal that distributes power to a speaker, while a two channel amplifier has two terminals that distribute power. Likewise with 4 and 5 channels amplifiers, it’s the number of routes available for information or power to flow.

    If you have ever heard the terms “mono” and “stereo” you most likely link that to a sound system. If music is recorded in “stereo,” it means that it has a left and right side, so the left side might output the sound of the guitar while the right side pumps out the vocals. Stereo is effectively 2-channels, so the recording engineers can choose to have certain music play on one side or the other at any given time.


    When you bridge two channels together, they create one channel. This is used most often in 2 or 4 channel amplifiers. If you have two channels but only want to run one speaker, the channels can be bridged, or wired together, to create one single channel. It’s exactly like a wooden bridge in that it connects two paths together as one (Learn more about amplifier bridging).

    Monoblock and Class D Amplifiers

    Monoblock and Class D amplifiers have only one channel that is typically used for powering one subwoofer at lower frequencies. I find this type of amp to be the best choice for running one or two subwoofers. How do you run two subwoofers off of an amplifier that has only one channel? This can be a headache for those who do not know the difference between series and parallel wiring. If you have two subwoofers, you can wire the subwoofers together in series or parallel and then wire them to the amplifier.

    Two Channel Amplifiers

    A two channel amplifier can be wired in a few different ways because it has two channels which you can bridge together to create one channel. You can run one channel to each subwoofer, which acts as though each sub has its own monoblock amplifier hooked up to it. You can bridge the channels together into one channel and run one subwoofer or more, but this option forces you to run the amplifier at a 4 ohm load. While two-channel amps are a good option, I prefer to run a monoblock amplifier system.

    Four Channel Amplifiers

    A four channel amplifier has, well, four channels. This type of amplifier is mostly used to power speakers, not subwoofers. The average car has four speakers, two in the front and two in the back. Each channel connects to one speaker. Simple enough, right? But we can make this somewhat complicated by using subwoofers instead and bridging the channels together. If you have four channels (1,2,3,4), you can bridge channels 1 and 2 together, and then bridge channel 3 and 4 together. So you end up with two channels total. You cannot bridge those two channels into one channel; it will end up destroying your amplifier. The majority of the time, when a channel has been bridged, it turns into a four ohm channel. So if you have two channels, each at 2 ohms, and then bridge them together, it turns into four ohms (I will address ohms soon, so don’t worry!).

    Single/Dual Voice Coil Subwoofers

    Now I have to introduce the two major types of voice coils, Single Voice Coil (SCV) and the Dual Voice Coil (DVC). You will see this a lot as you look through different subwoofers. A SVC subwoofer has one voice coil and one set of terminals, one positive (+) and one negative (-). A DVC subwoofer has two voice coils, each with its own set of terminals. Because of this, DVC subwoofers offer more wiring options than SVC speakers. You will see that most DVC subwoofers can be wired at two different ohm levels, unlike a SVC which can be wired at only one ohm level. There is little to no difference in sound quality between the two types of subwoofers.


    First let’s check the dictionary’s definition of an ohm. “A unit of electrical resistance equal to that of a conductor in which a current of one ampere is produced by a potential of one volt across its terminals.” Confusing right? Don’t worry, sometimes I have trouble understanding it too! Basically, it’s the resistance to the flow of energy. The higher the ohm, the more resistance. So, 2 ohms has less resistance than 4 ohms. Amplifiers often give their power ratings at 2 ohms and 4 ohms. You will notice that the power rating at 4 ohms is less than the power rating at 2 ohms, or even 1 ohm on some amplifiers. The goal is to buy an amplifier and subwoofers that will give you the most power when you wire them together.

    Parallel Wiring

    If you have two parallel lines, it usually means they run next to each other but never touch. Parallel wiring is similar to it. If you wire in parallel, you would hook all of the positive speaker terminals together on one line, and all of the negative speaker terminals on the other.

    Series Wiring

    Series wiring can become a bit confusing. You take a single current path and arrange it among all of the components. It effectively makes a chain, so everything is hooked together as one. The parallel wiring, you would hook together similar terminals only, instead of wiring everything together.

    Series/Parallel Wiring Charts

    Single Subwoofer Wiring

    OHMS Voice Coil Parallel Series
    1 Ohm DVC 0.5 Ohms 2 Ohms
    2 Ohm DVC 1 Ohm 4 Ohms
    4 Ohm DVC 2 Ohms 8 Ohms
    6 Ohm DVC 3 Ohms 12 Ohms
    4 Ohm SVC N/A 4 Ohms
    8 Ohm SVC N/A 8 Ohms

    Dual Subwoofer Wiring

    OHMS Voice Coil Parallel Series
    1 Ohm DVC 1 Ohm 4 Ohm
    2 Ohm DVC 0.5 Ohm 2 Ohm
    4 Ohm DVC 1 Ohm 4 Ohm
    6 Ohm DVC 1.5 Ohm 6 Ohm
    4 Ohm SVC 2 Ohm 8 Ohm
    8 Ohm SVC 4 Ohm N/A

    Combining Subs and Amps

    Hopefully you have a greater understanding after reading the terminology section. This next section is aimed at helping you find the perfect amplifier and subwoofer combination. If you did not understand any of the terminology, the subwoofer wiring chart will help you out. The chart is based on a one channel amplifier wiring setup. If you have two subwoofers, it assumes you are wiring them to a single channel. If you have two subwoofers and two channels, you would look at the “1 Sub” section, because each sub gets its own channel. In the end, the power of the amplifier needs to equal the power of the subwoofers. For example, and amplifier that has 400 watts should be paired with one subwoofer that runs at 400 watts, or two subwoofers that run at 200 watts each. Regardless of the combination, the main goal is to equal out the power while running the products at their respective continuous power ratings.

    Alright, so let’s say you buy two Kicker 10CVR124 subwoofers. Each sub has an RMS power rating of 400 watts, and each subwoofer is a 4 ohms, Dual voice coil sub. Scan the chart for 2 subwoofers, then find the matching ohm level and voice coil type. So, we look for the DVC (Dual Voice Coil) and then the 4 Ohms right next to it. From here we see that It lists the ohm levels that wiring these subwoofers together in series or parallel will produce. So looking at the chart it says these two subwoofers can be wired in parallel at 1 ohm or series at 4 ohms. Remember what I said about the ohms? The lower ohm level has less resistance. So let’s choose a 1 ohm stable amplifier to give these subwoofers the most power! Because each subwoofer runs at 400 watts RMS, we need to find an amplifier that runs at around 800 watts RMS.

    Let’s look at a Monoblock, or single channel amplifier. The Rockford Fosgate R750-1D monoblock amplifier puts out 750 watts at 1 ohm at one channel. While it is not exactly 800 watts, we do not have to be perfect. Just don’t go too much over or under. As it is, this would be a near perfect match. If you decided to wire the subs at 4 ohms, you would have to find an amplifier that puts out 800 watts of power at 4 ohms, which can be very expensive.

    Let’s keep the same subwoofers but choose a two channel amplifier. Assume we will not bridge the channels. This changes things a bit, because you need to act as though you have one subwoofer instead of two given that each subwoofer has its own channel. So in this case, we look at the chart for 1 subwoofer, with a dual voice coil, at 4 ohms. It says in Parallel it wires to 2 ohms, and in series it wires at 8 ohms. Lets choose the 2 ohm stable amp to get the most power. I found an RE Audio CTX-1600.2 amplifier which has 700 watts of power bridged at 4 ohms (each channel has 350 watts of power at 2 ohms). Each subwoofer gets one channel, so each subwoofer gets 350 watts to it. This is just about right since each subwoofer has an RMS power rating of 400 watts.

    If you took the same amplifier and bridged the channels together, once bridged they stay at 4 ohms. So while these subwoofers would still work, you would have to look back at the 2 subwoofer chart. It has to be wired in series, because this amplifier is not 1 ohm stable.

    I would not recommend a 4-Channel amplifier for subwoofers, but if you have to have one, just know that you will not be able to find an amplifier that puts out 400 watts each channel. However, you could bridge each of the channels together, making it a 2 channel amplifier. In this case you would need to bridge a 4-Channel amp with power levels at 200 watts per channel. Once bridged it turns into 400 watts at 2 channels. Does this work with our subs? According to the chart, a bridged four channel amp is classified as a two channel amp. Since each sub gets a channel, you will also look at the 1 Sub section on the chart. The chart tells us that a 4 ohm dual voice coil wires to 2 ohms or 8 ohms, not 4 ohms. Since the subwoofers we choose can only be wired at 4 ohms, you would need to find a different set of subwoofers that are suitable for 2 or 8 ohm loads.

    Now you should be ready to start building your own system. Besides an amplifier and subwoofers, you will need to purchase speaker wire, wiring kits among other install accessories. Call us at 1-877-BUY-SONIC if you have any questions along the way.

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