How to Troubleshoot a Vintage Stereo

By Lee Grayson
Early players had one sound channel.

Alan Dower Blumlien assembled a working stereo system in the late 1930s and is generally considered to be the Father of Real Stereo. The stereophonic recording process is an attempt to re-create live sound by capturing it with sensitive microphones on two channels for playback on specially designed stereo components. It is another term for an audio system. Stereo components were mass produced in the 1950s but didn't see large sales until late in the decade when the costs were reduced for the average audiophile. By the late 1960s and 1970s, stereo components were found in most homes. Vintage stereo sets are finding a new popularity with fans wanting to play vinyl records.

Check the User's Manual: This is the easiest step and the place most people end up after all other options are exhausted. Stereos, particularly "high-end" units, were packaged with a schematic chart and a troubleshooting list that was exclusive to the set. If the stereo does not have the specific user manual, check online for free documentation. Duplicate materials for Akai, Pioneer, Sony, Dynaco, Kenwood, Marantz, JVC, Technics, Yamaha and Onkyo are easily found. Instruction guides for Sansui, Nikko, Carver, NAD, Luxman, Tandberg, Realistic, Bose, Accuphase, Teac and Nakamichi are less readily available, but not impossible to find. If free manuals are not available, check commercial online sites for duplicated or PDF files. Try posting a note on club or fan websites. There may be a member with your exact set who may be willing to send a copy for the price of duplication.

The stereo will not turn on: The easiest check is examining the power cord. Make sure the wall socket is working and then check the power cord for any damage. Take the cord between both fingers and work your way up the cord, checking to see if there is any indication of a break (both inside wires and outside insulation) or if the cord has a smaller diameter in one spot. Furniture may have been placed on the cord, smashing the interior wires. Lay the cord flat on a smooth surface. If it does not make a straight line, there may be damage at the point where the cord curves or bends. Check the connection at the plug for fraying or internal damage by lightly moving the plug back and forth. There should not be any "play" in the cord near the plug. The wire should be stiff.

The lights are on but nothing functions: If your stereo uses tubes or fuses, you will need to check these to determine if there is a problem. Tube and fuse testers (ohm meter) were commonplace in drug stores decades ago, but now are more difficult to find. Call local television repair stores. They may be happy to test the items. They may even have the exact replacements to fit your unit. If the stereo is solid state (uses transistors), you will need to take the unit to a repair shop unless you own equipment to test the transistors, have the skill to do the testing, and own soldering equipment to make the repairs. If you are unsure if the unit uses tubes or transistors, check the rear openings. Tubes are clearly visible, if they are used.

No sound from either speaker: Check turntable, radio and any other feature separately to determine if this is a general failure or an isolated problem with one component. Test one of the speakers, then hook up the other to test again. If the stereo has an "A" and "B" speaker option, test each channel with the speakers, making sure that the wires are connected to the correct terminals. The lack of sound might be linked to the use of headphones. Some headphone selector switches disconnect the speakers when pushed, so make sure this button is not depressed. Also, check to see if the Tape Monitor switch is on or off.

Fuzzy sound from one or both of the speakers: Lightly sand the connections and check the speaker wires attached to the rear of the unit. Re-cut the wires and wrap the connections tightly. If this does not work, change the speakers and test again.

Difficult to adjust volume, bass or treble levels: Dirty knobs may be the problem. Corrosion on the rheostat that controls loudness may create problems in adjusting stereo levels. A non-toxic cleaner and a soft cleaning cloth will take off any corrosion. Be sure to clean the connection and inside the knob. A step-by-step video illustrating how to do a quick clean up is available from eHow at: http://www.ehow.com/video_2369817_cleaning-knobs-vintage-audio-equipment.html

Sudden loss of power to the unit: Use the machine for at least an hour to test reliability. Older transistors will exhibit strange behavior when overheated.

Loss of volume or sound to one channel: Check the balance control knob to make sure it is working. Loss of sound or sound playing only at low volume may also be related to overheated transistors.

Tip

When troubleshooting a vintage stereo system, it is recommended to assemble two sets of test speakers and more than one turntable, since the problems may be in the components. Label each component with an "A" and "B" and begin by connecting the entire system before changing components.

Warning

Make sure to turn off the power when changing the components.

Never open the rear panel of any component.

About the Author

Lee Grayson has worked as a freelance writer since 2000. Her articles have appeared in publications for Oxford and Harvard University presses and research publishers, including Facts On File and ABC-CLIO. Grayson holds certificates from the University of California campuses at Irvine and San Diego.