Question: Can a stereo phono cartridge be used to play a mono LP record?

Answer: Generally speaking, yes, but if it is a true mono record, better performance can be obtained by using a true mono cartridge. So, what exactly is a true mono record you ask? Vinyl records can be either mono or stereo and each differs greatly in the way that it is recorded and cut. Cutting refers to the mechanical process of imprinting the recorded signal into the record surface. A heated cutting stylus literally cuts the signal into the soft surface of a lacquer-coated blank disc from which vinyl copies will ultimately be made. True mono records are cut laterally: The cutting stylus moves from side to side, cutting the same signal in both record groove walls. We refer to this as horizontal modulation. The playback stylus, therefore, requires compliance (movement) in the horizontal direction only. By contrast, stereo records are cut in both lateral and vertical directions. The cutting stylus moves not only from side to side but up and down as well, therefore the stereo playback stylus requires compliance in both directions.

A stereo cartridge will never quite faithfully reproduce the true mono signal accurately because it is not restricted to horizontal compliance only. Some phase and tracking errors will exist. Additionally, there will be some amount of cross talk between the cartridge’s independent left and right channels. A true mono cartridge eliminates these problems by producing only one signal and distributing the signal to both channels equally; the signal appearing in the left and right channels will be identical. This arrangement produces a sound that is more focused (centered) and has more weight (punch). An additional benefit of the design is that of surface noise reduction. When the same exact signal is reproduced at the same time by two speakers, the signal-to-noise ratio is improved.

Note: A mono cartridge should not be used to play back a stereo LP record unless it is specifically stated that the cartridge has appropriate compliance in the vertical direction. Our AT33MONO moving coil cartridge is one such cartridge.

If you have any questions regarding the playback of your mono LP records, feel free to contact the Audio Solutions Department.