Why should you use a dedicated mono cartridge for playing vinyl mono records?
On a mono record the signal is cut only in the lateral dimension whereas a stereo record is cut at +/- 45 degrees into the opposing groove-walls, see the below figure.
A stereo cartridge will be able to replay stereo and mono records, because mono is a special version of stereo where the right and left channels are identical.
While a stereo cartridge can play mono records it can’t achieve the same signal precision between the two channels. A mono cartridge produces but one signal that is directed to both channels in the system. A mono cartridge playing a mono record produces a more forceful and stable image with a fuller, more impactful sound.
Another big advantage in using a mono cartridge to play mono records is the absence of response to vertical movement. This means that a mono cartridge is basically immune to the pinching effect which comes into action when the stylus is pushed vertically upward in very narrow grooves. Also the response to dust, dirt and wear is reduced substantially. The final result will be a clean and noiseless reproduction of the mono record.
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