How to Test an Amplifier

Once you have come up with an idea of boosting up your audio system efficiency, amplifiers are the first products to think about. Even for newcomers, their choice turns out to be simplified, since there are a wide range of expert recommendations and pieces of advice on how not to miss that perfect solution which will suit your particular objectives.

As soon as you receive one, the task to see if it works shouldn’t be a challenge. However, a few really know where it is worth starting with. If you are about to hook up this electrical equipment, it is a must to ensure the right polarities are selected to link different gadgets. Otherwise, it might lead to a pitiful and costly damage to your system. Keep in mind the following steps to be aware of how to test an amplifier to see if it works.

Preliminary Verification and Validation

The very first thing consumers have to do is to check the quality of chassis. It is not recommended to make any sort of experiments with goods which have some bad-looking components, burn marks or melted parts (this is especially true for second-hand tools). If the amplifier seems to be in a good state, one of the simplest methods is just to make a proper connection of the machine’s wires with the battery.

Please note that power and ground wires are necessary for a hook-up. They are red and black correspondingly. The first one has to be connected with the positive battery’s post, while the second wire is to be linked to the negative post. Such a procedure doesn’t require mounting hassles, but a few amps may need to be grounded. In case an amplifier under the check works fine, customers will see the machine is switched on and the power light to turn on.

If this scenario doesn’t take place, there is another thing to test — all available fuses. The minimal quantity is one, and you can find it located in the machine’s chassis. Signs that signalize the problems lie not in the bad circuitry but in a damaged fuse are any corrosion or cracks in the latter. On the one hand, you can give a try to another amplifier. On the other hand, it is possible just to replace a fuse. That is a way of how to test an amplifier without a car.

Amplifier and Speaker Combo

When it is obvious the amplifier consumers possess is capable of accepting electrical signals and 12 volt power coming in, it is a high time to link it with the speaker. For that action, prepare RCA cables or speaker wires. If they are not included in the original amplifier box, you should take care of that beforehand.

When you are done but nothing happens, it is an indicator that the amp’s state isn’t as good as expected. If the speaker starts performing after connecting with the machine, check the sound quality is. The latter doesn’t have to be fuzzy or distorted. If that’s not your case and you hear clear and bright notes, congratulations — you have found a nice solution for your needs.

Multimeter Testing

The use of auxiliary tools may seem unnecessary and annoying for customers, but this method of testing will help you be up in arms and get a deeper insight into how your system performs. Multimeters are easy to purchase on the market, and they are absolutely affordable for different categories of users.

In plain English, such devices are applied when there is a need to test how appropriately the electronic circuit functions. They measure voltage, resistance, and current levels.

Some features vary, but basic principles are the same. If you would like to experience more user-friendly options, then digital multimeters have to be considered instead of analog alternatives. In order to get how to test an amplifier with a multimeter, feel free to follow the next steps:

• The first thing of the test is to locate the amplifier itself. For this method, it doesn’t really matter where you are going to install the product. Unlike general car solutions, amplifiers come in handy for bikes, boots, tracks, etc. The manual provided by the manufacturer isn’t recommended to omit. It is the right tool to avoid typical installation mistakes.
• There are cases when the amplifier is equipped with more than just one plug. Then users are to select the main one. For its identification, you may simply look for a 12V+ marking. In other cases, the wiring diagram will be of great value.
• Before connecting the multimeter to the amplifier, take a look at the amp’s fuse(s) and protection mode. The activation of this mode is an indicator that the solid performance of the equipment is under debate. For testing, this mode has to be switched off.
• When it is the right moment to implement a multimeter into your system, it is necessary to link the red lead of the device to the positive terminal with a “+” sign and the black one to the ground or common ground with the negative connection.
• The test itself will provide enthusiasts with information about what amount of volts comes out from the wires.
• The output frequency is to be analyzed when the multimeter wire is plugged in the output channel. If there is no text to appear, it means that your speakers don’t work. The reading points if there are any issues with the connection.

There are a few more tips for those customers who can’t find any connection issues but still fail to achieve the necessary results:

• One of the hidden problems that are performance-influential is the amp’s mount location. If it touches the vehicle’s metal though the screws or directly, you should either replace the device or add any non-conductive materials in-between in order to avoid the reaction of the kind.
• The right power and ground are necessary to make the amplifier work correctly. With additional devices like multimeters, you can check whether your eyes are not deceiving you. Zero ohms have to be shown on the display when the system is turned off. The voltmeter check should result in twelve volts in the switched-off state and fourteen volts in the running mode. If you see different information, the connections may be loose and thus the amp doesn’t receive enough “fuel” for its well-being.

Professional Measurement

For those enthusiasts who would like to check whether the data provided by the manufacturer is true to life, there is a more advanced check. Apart from verifying the amplifier output, individuals are eager to know the accuracy of gain, frequency response, signal-to-noise ratio, THD, and more. Instead of using separate instruments for each test, there are universal solutions like specialized audio analyzers to maintain this quality testing of sound products.

If you are to find any signs of poor sound fidelity, then an oscilloscope will be your lifesaver. In simple words, this machine is designed to test electrical currents by displaying the input waves and their shapes. It may be a complicated task for newcomers, but experts prefer it to verify signal distortion, blown fuses, improper biasing occur and has a bad impact on the system’s performance. There is a rule of thumb to bear in mind: the smoother the shape is, the better sound it represents.

Working with an oscilloscope, you will deal with the chassis ground and circuit board, so it is necessary to remove the panels of the amplifier to arrange this test. Once again, positive and negative leads of the amp and extra equipment are to be matched. The amplifier has to be running during the check, but, instead of connecting it to your speakers, link it to a function generator to get the right amount of power.

It would be easier to understand how to test an amplifier with an oscilloscope with the illustrative example. Feel free to check the link below: https://youtu.be/EpsUVc3lcMk.