When setting up a home theater, you need a receiver with two or more channels to create your desired cinematic surround sound experience. This is true once you have a 2.0 stereo system and higher grade surround sound systems.
If any of your receiver channels is blown, that means you have one less channel to connect a speaker which can really diminish your surround sound experience. In this article, we will show you how to fix a blown channel on a receiver.
To fix a blown channel on a receiver, start by checking if the controls are corroded and clean them. If that is not the case, check all cable connections, check the fuse, and fix any overheating issues.
Which Receiver Channels are Often Blown?
Any receiver channel can be blown at any time, especially when you turn up the volume too loud. In fact, all your channels can be blown at the same time. This means if you are using a stereo receiver, you can lose the two channels at once.
On the other hand, if you are using a surround sound receiver or AV receiver, you can lose all the multiple channels at once, rendering the receiver completely useless.
Remember that a typical 5.1 AV receiver has five channels, meaning they have 5 built-in amps with preamp connections in addition to a subwoofer preamp output.
Remember that modern receivers have advanced “protection circuits” that can identify dangerous volume levels and shut down automatically. In other words, they work as digital fuses. This limits the chances of your hardware getting damaged or blown, but it is still possible.
Any receiver channel can be blown. But the process of fixing them begins by evaluating the nature of the damage.
Is Your Receiver Channel Really Blown?
Before going into the various fixes for a blown receiver channel, you need to check if the channel is really blown. For example, many people seek out methods of connecting external speakers to their TV without a receiver if the channels are blown before trying to fix the issues with the receiver.
Just because a speaker connected to a certain channel is not working doesn’t necessarily mean the channel is blown.
Firstly, you need to switch out the speaker and also swap the connection cable and see what happens. If the replacement speaker doesn’t work or is still distorted, then you know there is an issue.
The most common possibility is the volume or balance controls are dirty or corroded. In this case, you might want to check and have the controls cleaned especially if you are experiencing distortion. They should be cleaned with contact cleaner. If this doesn’t fix the problem, please continue with the steps below.
The following are the tools that you will need to attempt fixing your receiver:
- Phillips screwdrivers
- Soldering iron and solder
- Electrical contact cleaner spray – (Cleaning input jacks and speaker terminals)
- Compressed air
- Multimeter or continuity meter
Steps to Fix Blown Channel on a Receiver
1: Check Cable Connections
Firstly, turn everything off. Now, evaluate all the cables and confirm whether they are properly inserted into the receiver and any other important hardware in your sound system.
If you are using wired speakers, be sure the cables are firmly plugged into the receiver’s speaker connection ports.
If the system is properly connected, there could be a different problem, so move on to the next step.
2: Examine the Fuse
Step 1: Check If a Fuse Is Blown
In most cases, the real issue is that the fuse gets blown and not the channels themselves. If you play the volume too high on the receiver, the fuses may short out or the knob on the fuse knob on the back of the receiver may turn off.
Unplug the receiver for safety reasons, then check your system and ensure there are no electrical issues and all the devices are properly matched then and turn the knob on. For example, a fuse may blow because something it feeds shorted to ground.
If that fails to solve the issue, carefully check whether the fuse is damaged. You can tell it is damaged if the metal filament in the middle is broken or appears black.
Check the fuse using a continuity meter or a multimeter. You can get a multimeter/continuity metetr on Amaon like the AstroAI Digital Multimeter with Meter Continuity Test. Again, sometimes you may notice a dark discoloration within the fuse, indicating that it is blown.
Irrespective of the condition of your channels on your receiver, you must first fix the fuse if it is damaged before you can solve any other issue. In other words, to fix blown channels, you must start by fixing the issue that caused the blown fuse and then replacing your damaged fuses.
Step 2: Pull the Fuses Out
Ensure you check the system for any electrical issue and ensure correct impedance matching.
Now, carefully pull out the damaged fuses to assess them further. Sometimes, you can only tell whether the metal strips inside is burnt if you remove the fuse.
However, you need to be careful because the glass may break. Try sliding the fuses in and out. If that doesn’t work for you, use a screwdriver to unlock the case that protects the fuse.
Step 3: Replace the Fuse
Assuming you ascertain that the fuse is blown, you need to go to the next step of replacing the fuse. New ones are readily available in most electronic shops. Moreover, you can get fuses online.
Note the rating of the fuse before replacing it so that you get the correct one. Fuses are rated in terms of voltage and current, e.g a 250 V 10 A fuse. Fix the replacement firmly, using a screwdriver to lock back the protective case.
After fixing the fuse, test the receiver to ascertain whether you have fixed the problem.
Step 4: Turn on the Receiver
Plug in your receiver and then turn it on. If power gets to the receiver, you have fixed the issue.
If not, you need professional help. Most modern components are delicate and get damaged easily. You can easily destroy them further if you are not an expert.
3. Clean the CD Tray (Older Receivers)
In some cases, all you need to fix your receiver is spray compressed air into the CD tray to remove dirt on the CD player. Dust can limit the capacity of a receiver to read an inserted CD.
4. Check For Overheating
Of course, this is a small issue provided no hardware is damaged. You can use the owner guide from the manufacturer to reset the protection trip.
5. Check For Shorted or Blown Transistors
Transistors are very important electronic components and if you open your receiver, you likely see several transistors inside. In fact, you may notice 1-2 huge transistors for each channel bolted onto the main heatsink.
These electronic components blow rather easily so you will want to check if any of them are shorted. Here is how you can do that.
Change your multimeter mode to diode mode and then check the leads of both polarities. They should never read 0, if they do, the transistor is blown.
Most topologies, in-circuit, should never yield a 0V reading across any leads in either polarity. If you see, you’ve probably got some deadness.
You can also directly check the check resistance between collector and base of the transistor, if it’s 0 it’s blown. Of course, you can use a continuity meter to do this as well.
If you have transistor pairs, then check only the center pin on each pair. Keep in mind that all left transistors in each pair reads 0V on the center pin and all Right reads 50VDC and 110VAC on the center pin. However, the voltage on the R pins and L pins vary.
6. Seek Professional Help
If you have gone through the fixes the receiver still powers on but turns off after a while or fails to perform its functions and power the channels, we do not commend a quick fix at home. You can save a lot of time and wasted effort by seeking professional help.
The process often involves replacing the blown components. For example, you may have shorted output transistors which can damage other circuits.
How to Know a Channel on Your Receiver is Properly Fixed
Before you conclude that the blown channel on your home theater receiver has been fixed correctly, check if it’s performing all its functions properly. Your receiver should be able to do the following:
- Connect and switch video sources
- Connect and switch audio sources
- Decode surround-sound formats
- Amplify audio signals
- Drive multiple speakers
If you suspect that any of the channels on your receiver has been blown, troubleshoot to detect the exact problem.
By using the above steps, you will be able to fix the issue quickly or at least rule out certain possibilities. If the hardware has been damaged, it is best to seek professional help or a replacement.