FAQ’s

If your amplifier’s main power wire has a fuse in-line that keeps “blowing”, it can be related to the wire itself or the amplifier. You can tell if the problem is in the power wire by disconnecting the amplifier from the power wire, and insulating the amplifier end of the wiring from grounding against the body of the car (using electrical tape for this will work just fine). Then, simply put another fuse into the wire – if it blows, then somewhere along that run of power wire you have a cut in the insulation (or jacket) where the wire itself is touching the metal of the car. Pay particular attention to the point in the car where the power wire runs from the engine compartment into the car’s interior. If the hole that was drilled does not have a grommet and is unprotected, the sharp edges of the hole may have worn through the insulation of the wire, causing it to “ground out”. Additionally, try looking for any point in the wire that may be caught by moving panels, doors, or trunk components. Any bare wire that sticks through the insulation should be trimmed back, and that break in the insulation should be repaired with electrical tape or heat-shrink tubing. If the fuse does not blow when the amplifier is not hooked up, then the amplifier is most likely the cause. In most cases, an amplifier will blow fuses due to internal damage caused by the way it was installed. Many times, an amplifier won’t show signs of improper installation until it’s too late, and blowing fuses indicates that damage has been done. An amplifier that blows the main power fuse immediately after you turn it on or when the fuse is inserted into the fuse holder is usually damaged in its power supply or output section, and will require serviced. Improper Gain and/or Bass control settings, low impedances, or blown/failing speakers are the most common causes of this trouble.

Most of the time, low-impedance loads are the primary cause of blowing out a channel or possible speaker failure. Refer to your owner’s manual for the minimum recommended impedance for your amplifier. Also be sure to check out our Woofer WiringWizard which shows proper wiring methods for subwoofers. Improper level settings can also cause problems with breaking amplifier channels. If an amplifier’s Gain or Bass controls are turned up too high, it can cause “excessive clipping”. Excessive clipping occurs when the gain or bass controls on the amplifier are set to a higher sensitivity than they should be, based on the signal level coming from the source unit (or another processor before the amplifier). Excessive clipping may make an amplifier shut down early from thermal or overload protection, or can cause speakers to sound distorted. Excessive clipping does not burn up speakers, excessive power does as we’ll explain below. For example, if you have a 4-Volt source unit and the gain control at the amplifier is set all the way up (it’s most sensitive position – it thinks you’re sending 500 millivolts (0.5 Volt) into the amp,) the amplifier will make full power almost immediately! As you turn the volume up higher, the amplifier makes maximum power right away and simply “holds” it there for a longer period of time. This extra time that the amp makes max power sounds like “distortion”, and sounds pretty bad, but it isn’t distortion – it’s the amplifier sending that extra energy (Power/Watts) directly to the speaker.  Excessive power applied to speakers can burn the voice coils! This problem can also be created by equalizers that have the bass levels adjusted way too high, as the specific frequency that gets boosted is being reproduced by the amplifier as best it can, but the amp cannot produce any more power than it already is making at that frequency, so it just “holds” the output level at maximum. The amplifier may shut down or blow its fuse to protect itself. If this scenario happens too many times, the amplifier will usually fail and require repair. In many cases, simply making the appropriate adjustments to the gain control will fix the problem.

Adjusting Gains by Ear This is the fastest and easiest method for adjusting system gains. The benefit is the cost which is FREE. It’s also fairly easy to do and only requires a screwdriver to adjust the gain controls. Step 1. Adjust source unit Bass, Treble, and Balance to their center position. Step 2. Adjust all amplifier gains and any Punch EQ to minimum. Without a Signal Processor Step 3. Play a music track with impactful bass, vocals and treble. Step 4. Increase the source unit volume to 3/4 (high performance source units to 7/8) maximum. Step 5. Increase the amplifier gain(s) until your preferred maximum loudness is achieved. If using amplifiers in bridged/mono mode or using two amplifiers in bd-SYNC mode, simultaneously increase both gain controls so they are balanced at the same level. With a Signal Processor Step 3. Adjust all signal processor levels to minimum. Step 4. Play a music track with impactful bass, vocals and treble. Step 5. Increase the source unit volume to 3/4 (high performance source units to 7/8) maximum. Step 6. Increase the signal processor level output until your preferred maximum loudness is achieved. If the maximum processor output level is reached and system still does not play loud enough, then slowly increase the amplifier gain controls until your preferred maximum loudness is achieved. If using amplifiers in bridged/mono mode or using two amplifiers in bd-SYNC mode, simultaneously increase both gain controls so they are balanced at the same level.

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Adjusting Gains by Meter This is the most cost effective method for adjusting system gains with predictable accuracy. This procedure references a DIY Distortion Meter as follows; 1) Mini-Amplified Speaker, 2) Source Unit Voltage Divider, and 3) Amplifier Voltage Divider. A link for building your own DIY Distortion Meter is at the end of this article. Step 1. Disconnect all speakers and RCA cables from source unit. Adjust Bass, Treble, and Balance to their center position. Step 2. Connect the RCA end of the “Source Unit Voltage Divider” to the source unit’s RCA output. Connect the 1/8″ jack end to the “Mini Amplified Speaker”. Step 3. Play a test tone, 1kHz @ 0dB. If source unit has a REPEAT TRACK function, press this button to provide adequate time to perform. Step 4. Turn on the “Mini Amplified Speaker” to a low listening level. Increase the source unit’s volume until the maximum output is produced without clipping (at clipping you can hear the tone change from clean to raspy). Stop the track when the test is complete. DO NOT change the source unit’s volume position. Without a Signal Processor Step 5. Reconnect RCAs between source unit and amplifier(s). Step 6. Disconnect all speakers from amplifier(s). Adjust all amplifier gains and any Punch EQ to minimum. Step 7. Connect the alligator clips from the “Amplifier Voltage Divider” to the amplifier’s speaker outputs. Connect the 1/8″ jack end to the “Mini Amplified Speaker”. Step 8. Play the test tone of your choice (0dB/-5dB/-10dB) for the desired gain overlap. Step 9. Increase amplifier gain(s) until maximum amplifier output is produced without clipping (again, listen for the tone to change from clean to raspy). If using amplifiers in bridged/mono mode or using two amplifiers in bd-SYNC mode, simultaneously increase both gain controls so they are balanced (at the same level). With a Signal Processor Step 5. Reconnect RCAs between source unit and signal processor(s). Step 6. Disconnect all speakers from amplifier(s). Adjust all amplifier gains and any Punch EQ to minimum. Step 7. Connect the alligator clips from the “Amplifier Voltage Divider” to the amplifier’s speaker outputs. Connect the 1/8″ jack end to the “Mini Amplified Speaker”. Step 8. Play the test tone of your choice (0dB/-5dB/-10dB) for the desired gain overlap. Step 9. Increase signal processor gain(s) until maximum amplifier output is produced without clipping (again, listen for the tone to change from clean to raspy). If the maximum processor output level is reached and system still does not play loud enough, then slowly increase the amplifier gain controls until amplifier reaches the threshold of clipping. If using amplifiers in bridged/mono mode or using two amplifiers in bd-SYNC mode, simultaneously increase both gain controls so they are balanced (at the same level).

Equalizers are used to help compensate for acoustical inaccuracies common in the automobile environment. The boost/cut controls on the equalizer increase or reduce emphasis in a specific octave of music. When used properly, an EQ can help overcome dips and peaks in the response curve. What to Listen For The sound of the audio system should be natural without excessive “hot spots” in the audio spectrum. A breakdown of the audio frequencies are listed below: Sub-Bass: Low frequencies produced by bass guitar, kick drums & drum machines should be easily recognizable and not be over-exaggerated. A desirable bass level should be present at the same relative amplitude as the rest of the frequency spectrum. Mid-Bass: Middle bass frequencies produced by bass guitar, piano and synthesizers should be reproduced with good detail. Listen to the intensity of drums and bass guitars because many vehicles have resonating problems (vibrations & rattles) that cause peaks in the response. Mid-Range: The middle frequencies produced by the human voice, guitar, percussion and brass instruments should sound realistic without any harshness or distortion. High-Frequencies: The high frequencies produced by cymbals, snare drum and higher notes on percussion instruments should sound accurate without excessive brightness. No blurring or hissing of the human voice should be heard. To Boost or Cut? Although it’s tempting to crank up each equalizer’s setting to the maximum boost level, this rarely achieves the desired result. What you’re actually doing is just increasing the amplitude of the system. By turning up the amplifier’s gain control, you can also achieve the same result and thus increase the signal-to-noise or “hiss” in your system (this is not necessarily a good thing). How to Equalize Properly Although it sounds strange, we recommend setting the equalizer boost/cut controls to the center (flat) position and using the EQ as a “cut-only” device. Use the equalizer to minimize the differences between neighboring frequencies. Use the equalizer to keep acoustic deviations under 3dB. If you find that you are using 9dB or more to “fix” a problem area, suspect something incorrect in the system design such as an incorrect crossover setting, improper speaker phase, or even a blown speaker.

The best method when matching speakers to amplifiers is to use the “RMS” power ratings instead of “Max/Peak” power ratings. It’s important to note that most speaker manufactures publish two different power ratings: Speaker “RMS” Power Rating The “Nominal” or “RMS” (root-mean-square) rating is the amount of power that can be applied to the speaker under normal circumstances. One of the primary factors that determine the power rating of a speaker is the size of it’s voice coil. A speaker with a high power rating uses a large voice coil, allowing more heat to be dissipated and therefore allows more power to be applied to the speaker. Use this power rating to match the speaker’s “RMS” capacity to an amplifier’s “RMS” output. For example: if your speakers are rated to handle 50 watts RMS each, then select an amplifier that will deliver approximately 50 watts RMS to each speaker. Speaker “Peak” Power Rating The second is the “Max” or “Peak” rating which is the maximum amount of power that can be applied for short periods of time without causing damage. If the peak power rating is exceeded for an extended period of time, there is danger of overheating and deforming the voice coil. Do not use this power rating for matching speakers to amplifiers. It is for informational purposes only. Do not match the speaker’s RMS power rating to an amplifier’s Max/Peak power output. For example: If your speakers are rated to handle 50 Watts RMS each, and you select an amplifier that will deliver 125 watts RMS per speaker, you will likely apply too much power for the speaker to handle. This can cause a voice coil to literally “burn” and possibly “short-out,” rendering it inoperable. In our question above “Do I need a 200 watt amplifier to drive a 200 watt speaker?” the answer is simply “no”. A 200 watt RMS power rating is how much power a speaker can handle, not how much it requires. Even a 200 watt speaker can sound great with only 30% (60 watts) power applied. However, you’ll have low SPL (sound pressure level) or “loudness” with this little power. Sample Amplifier Power Rating Chart: