Memphis car audio

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Memphis car audio

Text of Memphis car audio

MAXIMIZE your MEMPHISUse this TOOLKIT to MAXIMIZE the enjoyment of your music by MAXIMIZING the performance of YOUR MEMPHIS CAR AUDIO system.VERSION 2.0Memphis Car Audio Quality Statement (what we believe about our products) We are confident there will be practically 0 failures if every Memphis Car Audio partner and customer installed and operated our products according to the product guidelines. A failureThank you very much for taking the time to invest in your stores future growth. Your business is very much a part of our business. As an independent Memphis Car Audio partner, you have already discovered what it takes to drive customers into your store. And you already employ talented installers and sales personnel. That is where having a great product line and a company that has your back fits into your stores profitability. is defined as any reason for one of our products to stop working properly. If you are not currently experiencing practically 0 failures with our products, we encourage you to become familiar with the contents of this manual. Your sales rep will work with you to help accomplish this goal. How to use this manual: Common Failures: This commentary provides further insight on typical causes for product failures. Product Application Guide: Designed to offer the best product combination between a given amplifier model and the desired quantity of subwoofers being powered. Each product family is color- coded for easier visibility. Please observe the proper wiring technique and recommended Memphis Car Audio enclosure (if available) under each subwoofer listed. The wiring action symbol(s) indicated are: "||" for parallel, "+||" for series-parallel and "||+" for parallel-series wiring. (See our subwoofer wiring diagram examples in this manual). Also, please note our recommended accessories for each amplifier application. Where an "X" is printed, no subwoofer models are available to work properly with that particular application. Extensive Product Application Guide: Created to help you determine all available subwoofer models that will work properly with each amplifier model. Compliance with this list is your first step in achieving lower product failures. Choose from a wider variety of subwoofer families and sizes on this list. Subwoofer Wiring Diagrams: Use these examples to establish the proper techniques necessary for series and parallel wiring. Subwoofer Power Handling Chart: Outlines the nature of each subwoofers power handling characteristics. Notice the yellow (optimum) regions, designed to give the best performance for each subwoofer model. Be sure to use the appropriate enclosure type based on which area of the power spectrum you are operating within. You should not apply an amount of power that falls in the Below Minimum Power category. The numbers above each color line indicate (from left to right): absolute minimum recommended power, lowest optimum power, highest optimum power, and absolute maximum recommended power. Exceeding the maximum recommended power number or going below the minimum recommended power will result in a voided warranty. Amplifier Gain Adjustments: Provides the correct settings for an amplifiers sensitivity range (gain) at the desired impedance. By not going beyond the AC output voltage listed for each amp, you ensure that an amplifier cannot create amplitude distortion (clipping), which in turn will greatly reduce the chance of product failures. For best accuracy, we suggest making final adjustments for crossover settings, subsonic filter, and bass boost settings before performing this process. To prevent damage to midrange speakers (or speakers that cannot be properly crossed over), we recommend disconnecting those speakers while performing this process. Enclosure Recommendations: All current Street Edge and Memphis Car Audio subwoofer models are listed on this chart for easy references to our recommended enclosure size. This chart is designed to interact with our Subwoofer Power Handling Chart recommendations. 1failureCommon failures and causesAmplifiersWhy does my amp go into protection mode and/or blow the fuse(s)?1. High gain or bass boost function setting, or improper crossover frequencyIf the amplifier gain (or bass boost) is too high versus the input signal, it will cause the amplifier to clip the output signal. The amplifier gain is actually a sensitivity control; it was designed to be set according to the audio input signal level. If less signal is available from the source unit into the amp, adjust the gain clockwise to match the amps sensitivity. If more signal is available from the source unit into the amp, less gain (counter-clockwise) is necessary to help the amp drive the signal to full output. Clipping an amp means to exceed the peak value of the amplifiers power supply voltage. This distortion of the waveform causes high current demand through the amplifiers output section. The transistors inside the amp will prompt the amps protection mode due to overload. Having a bass boost feature on the amplifier (or any external component, even the radio) can result in rapid clipping. A boost at a particular frequency (or band of frequencies) is added to the existing voltage- contributing to many amplifier failures! This can be best corrected by lowering the amp gain or bass boost (if applicable). This should be done by a certified installer.There are 3 common ways that amplitude distortion or clipping can be identified.x Use an oscilloscope to measure the signal voltage. If the peaks and troughs of the wave form are flattened out (figure 1) or the wave forms are not symmetrical, clipping is occurring.x Use a digital voltmeter to measure the voltage across the (+) and (-) speaker output terminals. This value should be less than (or equal to) the recommended amp rail voltage. If not, clipping is most likely occurring. (See the rail voltage chart in this guide.)x Some listeners can hear clipping audibly. The signal will sound choppy or have a static noiseor can be thought of as cutting in and out. Most listeners cannot hear this form of distortion unless the audio waveform is severely clipped.2. Not using the subsonic filter when appropriate (vented enclosures)A subsonic filter is designed to cut-off dangerously low frequencies from getting to the subwoofer, especially in a vented enclosure. The subwoofer(s) lose power handling rapidly when frequencies dip below the tuning frequency of a vented enclosure. A subsonic filter is a high pass filter that will remove unwanted and potentially damaging low frequencies from the subs. Subsonic filters are recommended for vented enclosures and are incorporated in our Class D amplifiers.3. Low battery voltageLow battery voltage (below 12V) creates the need for very high current demands to maintain constant output power through the amps power supply section. This causes heat and will reduce the available output voltage rail, even in an amplifier with a regulated power supply. This results in premature amplifier clipping, which may trigger the protection circuit. Conditions to check for this problem include (but are not limited to);x Poor ground wire connections (to the amp or the vehicle chassis)x Improper wire gauge being used for power and/or ground wirex Loose connections to other points (capacitors, battery(s), fuse or distribution block)x Not having sufficient capacity (batteries)x Not having a large enough alternator to keep batteries chargedWhen resistance enters the circuit path, voltage will drop across that resistance as current flows through it- leaving less available voltage at the amplifier. The alternator is the main device that constantly generates current (with the vehicle on). The battery(s) would be the reservoir that stores current and discharges it to the amp, and the amplifier is the root of current consumption. If there is a capacitor (or battery/or batteries) physically near the amp, it should be supplemental to the rest of your charging system.4. Low impedanceIf the speaker impedance goes below the amplifiers rated stability, high current flows through the amps output section transistors and may cause them to become saturated (shorted). This will most likely cause the amp to go into protection mode until the impedance becomes suitable for the amplifier to handle.Figure 15. DC offset DC offset generally comes from the source unit; it could potentially damage the input section of the amp and may be the root of the amplifiers protection status.6. Internal damageWhen an amp is internally damaged in locations other than the input power supply section, the unit will usually trigger the IC chip assigned to engage a protection fault condition. Therefore, there will not be an output under this condition. When this condition occurs, the amplifier must be repaired.What can I check for if my amplifier gets hot?1. Insufficient ventilation around the amplifier2. Loose connections to power/ground terminals on amplifier3. Low battery voltage at the amplifier4. Too low of an impedance connected to the amp5. An open audio signal ground in the RCA cables and/or within the amplifier traces6. Gain and/or amplifier settings improperly adjustedWhat is the relationship between using multiple amplifiers across multiple subwoofers that share a common airspace inside their enclosure?When multiple amplifiers are being used to power more than one voice coil (or subwoofer), symmetry among the amplifiers is of the utmost importance if the subs share a common airspace. This means that the low pass filter, subsonic filter, bass boost, and amp gain should all be set identically. Also, designing an enclosure with the subwoofers mounted equal distances from one another (and the port, if applicable) will help with an asymmetry problem. Do not mix single voice coil versions and dual voice coil versions of the same subwoofer in a common airspace together. If possible, use a small partition between multiple subs to cr