how to repair amplifier no sound Woman Sitting Near Technician Repairing Amplifier

Advice On How To Repair An Amplifier With No Sound 

Do you love listening to music? If you do, then you’ve probably invested in your home sound system by purchasing an amplifier.

Amplifiers allow you to control the balance of the audio so it sounds exactly how you want it to. But using them can be problematic if the amplifier begins to malfunction.

Here are some common issues people may experience when using an amplifier:

  • They won’t turn on
  • The sound being produced is distorted
  • There is a humming sound coming from the speakers
  • There isn’t any sound coming out of them at all

In this article, we will provide you with help on how to repair amplifier no sound.

But before we do that, let us explain a little bit more about what an amplifier does.

What Is a Power Amplifier?

Power Amplifier on Table

A power amplifier is an electronic device that helps to magnify and control the output of the audio source signal from a piece of home audio equipment – such as a CD player or an AM-FM receiver. This output signal is often passed through to a set of speakers.

An amplifier has several main components, including a power amp, preamp, and speaker. It is the preamp that helps to convert the audio signal into an electrical current.

The amp then receives these electrical currents and adds voltage to them, allowing the signal to be sent to the speakers.

Common Problems with Amplifiers

There are quite a few things that could go wrong with an amplifier. Before trying to perform any repairs on your equipment, you first need to identify the problem.

Of all the problems that may result in an amplifier not working, the most common one is the result of a person not knowing how to use the equipment correctly.

So you’ve turned it on and the light at the front is on showing that power is being received by the amp, yet there still isn’t any sound. This could be a result of the wires between the amp and the speaker not being connected properly. It could also be as simple as the operator failing to select the speaker button.

Also, you may find that it is because the wire leading from the amp to the power supply has been damaged. In this scenario you need to be careful – if too much power passes through the wiring, it could result in a blown fuse.

But one of the most common reasons for an amp having problems is that the jacks or electrical contacts in it have suffered from oxidation. The jack is the connector that is used to complete the circuit between various components (the amplifier, the speakers, or the preamp, for example). If the jack becomes dirty or covered in gunk then it will have reduced capacity to conduct electricity, which in turn means that the device it is connected to will not receive a signal.

In fact, what you will often find is that the problem doesn’t involve the amplifier at all, but is in fact due to an issue with the connection between it and the other device.

The quickest way to figure this out is by using a multimeter or a continuity tester. Either of these devices will allow you to check if there is a signal passing between the amp and speakers. This is something that you should do before you even consider opening up the amp to see if there is a problem inside.

How To Identify An Amp Problem

Identifying a problem with an amp is relatively easy. You will either have no power, no sound, or the sound being produced is terrible.

When it comes to discovering the source of the issue, this can prove a little more complicated. In some cases, you may find that the problem lies in the audio unit that feeds into the amp – such as an external CD player, built-in AM-FM receiver, or speaker.

Tips To Help Fix It

One of the first things you should do is remove all audio sources from the amp. Then use only the internal receiver in the amp to help determine if the unit is getting power or if the sound is good.

As soon as you open up the amp, look closely at the wiring. Has any of it come loose, or has anything been burnt? If there is an issue with the wiring, then you know this is probably the reason why you are not getting any sound from your amp.

As soon as you have identified the problem, you can then get on with carrying out the necessary repairs. However, before you even begin taking the amp apart, make sure that you have all the relevant tools and materials at hand.

What Will You Need To Repair An Amplifier?

Electronics repairs the audio amplifier

Whenever you are going to open up an amp to carry out any repairs or just to clean it, you will need the following essential tools:

  • The user’s manual for the amp
  • A Philips-head screwdriver
  • Some replacement fuses, transistors, and resistors
  • A soldering iron along with solder
  • An electrical contact cleaner or a can of compressed air
  • A Voltmeter

As soon as you have all these items together, you can move on to the next stage – how to repair the amplifier with no sound.

The Amp Is On, But No Sound Is Coming Out

You notice that your amp is working, but there isn’t any sound coming out. Well, there are a few reasons why this might be happening, and we look at some of the most common ones below.

Typically, in this situation, you will often hear some kind of sound coming out of the speakers, even if the signal path has been cut off.

If you listen carefully, you may hear hissing, humming, reverb crash, or popping sounds emanating from the speakers, especially when you disconnect or connect inputs.

Also, the issue may not be with your amplifier but with the actual speakers. It could be that the speaker has blown or the output transformer is faulty or open.

How To Fix Amplifier No Sound

In most cases, this problem is relatively easy to fix by opening up the amp and double-checking all connections between it and any device.

With amps that use Bluetooth connectivity, we would recommend trying to pair the device with it once again.

Hopefully, you’ll find that carrying out these simple tasks will soon have sound coming out again.

Steps On How To Repair Amplifier No Sound

Step 1

Turn the amplifier off at the main power supply and allow it to cool down for a few minutes. At the same time, make sure that the volume is set at zero.

Step 2

Now turn the amp back on once you’ve let it cool down. Check to make sure that the LED indicator is illuminated. This will show that the amp is receiving power.

Next, turn the volume up slightly to see if it will operate normally. Is there any sound coming out? If there is some sound, but the quality isn’t excellent, the amp is working but not to its full potential.

However, if there isn’t any sound coming out of the speakers at all, something is more likely broken.

Step 3

You must unscrew the amp’s back panel and remove the chassis. Once the chassis is removed, unscrew its lid, giving you access to the circuit board.

You need to look closely for any signs of damage, such as a blown transistor or fuse. They will have a brown color. If this is the problem, simply replace them with an identical part.

Step 4

Look at the wiring and soldering joints. Trace the circuit wiring from the input and gently pull on it. If it feels a bit slack, this could be the result of a loose connection.

To help improve this connection, use your soldering iron with a bit of solder to reconnect the wires. After you’ve finished soldering the wires together, remove any solder residue.

Step 5

Examine the amps circuit board, be sure to check if any capacitors or resistors have come loose. When this happens, the circuit gets shorted. The whole board will fail because the resistor is no longer performing its job of regulating the current.

Step 6

Here you will need to test the resistors. You will need a voltmeter that you place directly on the first resistor in the signal chain. Ensure the meter is set to “resistance” and turn the amp on.

When you turn on the amp, the voltmeter should provide a reading within 5% of the value of the resistor. This figure can be found printed on the side of each resistor. If the figure isn’t close to the variance, you have a malfunctioning resistor.

If you don’t get any reading, this shows that the resistor is blown.

Step 7

You will now need to turn the amp off to replace the blown resistor.

To do this, you first need to disconnect the solder joint from the base of the circuit board to allow you to remove the blown resistor. Then, simply replace it with an identical resistor and solder it into place.

Step 8

You need to unscrew the housing for the transformer to test its primary wiring. Before doing this, make sure the amp is turned off. Now attach the voltmeter to the wiring and turn the amp back on. Ideally, the reading should be around the same as power handling.

If you aren’t getting any reading, this clearly shows that the transformer coils have been shorted. However, if you are getting a high reading, it indicates that there is a leak from the transformer.

In both of these situations, the transformer will need to be replaced.

What To Do If The Amp Sound Is Distorted

Amplifier on hardwood floor

Some sound distortion can occur in amps that are damaged or faulty. However, the most common culprit behind such a problem is that of clipping.

This problem arises when there is a problem between the amp and the power supply voltage. To put it in basic terms it means that you are forcing the amp to use more power than it can generate.

Distortion can also occur if you regularly crank the volume up as loud as possible. It is important to remember that like any electrical device, amplifiers have their limits.

So How Do I Fix It?

If the distortion is due to clipping, then the quickest and easiest way to rectify the situation is to turn the volume down. Not only will this help to reduce the clipping, it will also help to get rid of the sound distortion as well.

However, if the distortion is a result of the amp being faulty or damaged, then you should seek out professional help to fix the situation.

Of course, it is a good idea to read through the owner’s manual that came with the amplifier (if you still have it) to see what they suggest you do to resolve such problems. You may find that the answer is something that is so simple, you may have never thought to do it in the first place.

Final Thoughts

We hope you find the above information on how to repair an amp with no sound helpful.

When carrying out such work, ensure that no part of your body is in contact with the amp as you test the transformer or resistors.

If you are unsure how to carry out such tests safely, ask a qualified technician or electrician to do them for you. This is because many power amplifiers store quite a lot of voltage in them that could be potentially dangerous to you.

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