There are many things that can cause a turntable to only play through one speaker. There can be a problem with the turntable itself, the cartridge, the cables, the amplifier, the receiver, the preamp, or one of the speakers.
In this troubleshooting guide, I will use my electronics engineering background and turntable know-how to do my best to help you find and correct the problem as fast as possible.
When troubleshooting a dead turntable channel, I recommend that you follow a 3-step process.
- Verify cables and connections
- Isolate the problem
- Troubleshoot the turntable
Step 1
We start with verifying that all cables and connections are ok. A defect cable or bad connection is usually easy to fix. And quite often what actually causes a dead channel.
Step 2
When we have secured that all cables and connections are ok, we need to make sure that it is the turntable that causes the problem. And not a defect amplifier or speaker. I call this step “isolating the problem”.
Step 3
When we have excluded all other possibilities, and we know that it is the turntable that causes the problem, then we need to troubleshoot the turntable itself.
Exactly how to troubleshoot a dead turntable channel will depend a bit on your vinyl setup.
The troubleshooting process for a full vinyl setup with a turntable, a preamp, and amplifier and speakers will be different to a simpler setup with only a turntable connected to powered speakers.
But the principals of troubleshooting will be the same, and you can follow this guide independent of your system. You simply have to adjust it to your setup.
Let’s go through each step systematically.
Step 1 – Verify cables and connections
The first thing we should do is to check that all cables are connected/secured properly. That there are no loose or bad connections. Do this by verifying that all jacks/cables are connected properly. One by one.
It is wise to rotate all the jacks on the sockets (jerk them back and forth) to “clean” the connections and create better electrical connectivity.
We also need to verify that we use the correct outputs and outputs for both left and right channel throughout the whole signal chain.
Verify that we use the correct inputs and outputs on the preamplifier (if we use one), the correct inputs on the amplifier/receiver, and the correct speaker connectors on both the amplifier/receiver end and the speakers end.
If you need tips on how to connect a turntable and how to set up a stereo, you will find many helpful articles on my blog here on Vinyl Restart.
The last thing to verify is that we don’t have a broken RCA interconnect cable. We do that by swapping the left and right channel on both ends of our RCA interconnect cables and check if the dead channel moves from one side to the other. Connect the red jacks on both ends of the RCA interconnect cables to the white connectors and vice versa.
If the dead channel moves when we swap both ends of an RCA interconnect cable, then one of the channels on that cable is broken. Replace that cable and your problem is likely fixed.
Do the same with the speaker cables. Swap the speaker cables and check if the problem moves from one side to the other.
If you have done all of the above, and the problem with the dead channel continues to stay on the same side, then it is likely that all connections and cables are ok.
In that case, we’ll move on to step 2 of the process.
Step 2 – Isolate the problem
To isolate the problem, we need to follow the signal chain and verify all the components that make our vinyl setup. One by one.
We start at the turntable and follow the signal chain towards the speakers, until we have found the defect component.
First out. The turntable.
To check if it is the turntable that cause the problem, we need to swap the left and right channel on one end of the RCA interconnect that connects the turntable to the next component of the signal chain.
NB! In this step we swap the jacks on one end of the interconnect cables only. We don’t swap the jacks on both ends of the cable like we did in step one above.
Here is how to do it:
- If your setup has a preamp following the turntable, then swap the left and right jacks that connect to the inputs on the preamp.
- If your setup has an amplifier/receiver following the turntable, then swap the left and right jacks that connect to the inputs on the amplifier/receiver.
- If your setup has powered speakers following the turntable, then swap the left and right jacks that connect to the inputs on the powered speakers.
If the dead channel moves to the other side after you have swapped the jacks, then we have verified that the turntable causes the problem. (Given that we have verified that all interconnect cables are ok in step one.)
If the dead channel stays on the same side, then the turntable is likely ok, and we need to do the same test further down the signal chain to check the next component of our vinyl setup.
Follow the process below to follow the signal chain and verify the components of your vinyl setup one by one. You may need to adjust the process to fit your specific vinyl setup.
- Swap the RCA jacks that connect to the inputs of the preamp. If the dead channel moves to the other side, then the turntable is defect. If not, continue to the next step.
- Swap the RCA jacks that connect to the inputs of the amplifier/receiver. If the dead channel moves to the other side, then the preamp is defect. If not, continue to the next step.
- Swap the left and right speaker cable on the speaker end. (Connect the right amplifier channel to the left speaker and vice versa). If the dead channel moves to the other side, then the amplifier/receiver is defect. If not, you likely have a dead speaker.
I hope that you understand the steps above and that you can use it to find which component of your vinyl setup that causes the dead channel.
Step 3 – Troubleshoot the turntable
If you have gone through step 1 and step 2 above to make sure that it is the turntable itself that is causing the problem, then you can use the steps below to troubleshoot the turntable.
Sometimes it is possible to find and correct the problem with the turntable ourself. But there will unfortunately be cases where we need to hand in the turntable in to a repair shop to perform “instrumented troubleshooting” to find the issue. Or invest in a brand new turntable.
That said, here are the steps you can take to troubleshoot a turntable that only plays through one speaker.
Check tonearm wires
Check that the thin wires from the tonearm is properly connected to the terminals on the cartridge. Fully disconnect the turntable and pull very gently in each of the four wires with tweezers or a small plier.
If one of the wires are loose, try to secure it with a small plier.
Check PHONO/LINE switch
If there is a PHONO/LINE switch on your turntable, it is a possibility that it doesn’t make sufficient electrical connection. Try to jiggle the switch gently while playing music to see if it fixes the dead channel.
Check headshell quick connection
If your turntable has a removable head shell, the headshell connection might cause problems. Try to jiggle the connection to see if it can solve the problem. Also, try to clean the connector with alcohol or a liquid cleaner suitable for cleaning electronics. Do not use water.
Conclusion
If you follow the steps above, you will hopefully find and correct the issue that causes your turntable to only play through one channel.
Fixing the problem will in some cases need technical expertise, but you should at least manage to isolate the issue and find out if it is the turntable that cause the problem. Or if there is a problem with another component in your vinyl setup.
I same cases, it will unfortunately be difficult to correct the problem without technical expertise. In those cases you may consider turning the defect component in for service. Or replace the defect component with a brand new one.