78RPM Ready

Moving Magnet 78 RPM Mono Cartridges

TL;DR: True mono vs modified Stereo Cartridges for 78RPM mono records. The primary difference is that a true mono cartridge is only designed to respond to lateral groove modulations, which reduces noise inherent in the vertical plane, while a modified stereo cartridge uses two coils that can be wired to respond to either lateral or vertical modulations by signal cancellation.

A true mono cartridge designed for 78 rpm records (which are typically lateral cut) has a single magnet/coil assembly oriented horizontally to the record surface, designed solely to detect side-to-side (lateral) groove movement.

Wiring: It only has two output signals. That being +/-. Even though there are four physical pins, they produce a single, pure mono signal. The 4 pin arrangement follows the same wiring as a stereo cartridge so that you can wire it to your stereo system without "Y" adaptors and the like yet still get a correct mono signal.
Performance: It inherently cancels out vertical noise, dust, and wear information, which results in a superior signal-to-noise ratio and clearer sound on the more common lateral-cut records.
Vertical Cuts: It is effectively "blind" to vertical (hill-and-dale) modulations, meaning it will only produce surface noise and very little of the intended audio when playing the less common vertical-cut record.
Media: You will have to research each record you want to play but the vast majority of 78s are lateral cut.

Modified Stereo Cartridge (Two Coils Wired Together)

A standard stereo cartridge has two magnet/coil assemblies positioned at 45-degree angles to the surface of the record to pick up both left/right stereo channels, which translates to a sum (L+R) in the lateral plane and a difference (L-R) in the vertical plane.

By wiring the two coils together, the cartridge can be configured to favor one type of modulation:

1. Parallel or Series Wiring for Lateral Cuts

Wiring: For standard lateral-cut 78 rpm records, the two channels are typically wired in parallel (or series, though parallel is more common/recommended for optimal loading) with the positive terminals connected and the negative terminals connected. This electronically sums the L+R signals.
Performance: This configuration sums the lateral information (the music) in-phase while canceling out-of-phase vertical noise information. It is effective, but generally considered inferior to a true mono cartridge because the cartridge assembly still has compliance in the vertical plane and some phase anomalies may persist.

2. Series (or Anti-Series) Wiring for (less common) Vertical Cuts

Wiring: For vertical-cut records (such as Edison Diamond Discs or Pathé), the wiring is modified to capture vertical modulation. The positive output of one channel is connected to the negative output of the other channel, with the signal taken from the two remaining free pins. This effectively puts the coils in "anti-series" to sum the L-R (vertical) signal.
Performance: This ensures the vertical information is in-phase and clearly audible, while canceling the unwanted lateral information/noise. A standard parallel-wired stereo cartridge would produce very low-level or out-of-phase sound when playing a vertical-cut record.

Summary

A true mono cartridge provides superior performance for its intended (lateral) cuts by physically ignoring vertical modulations at the generator level.
A modified stereo cartridge offers versatility through specific wiring configurations to play back both lateral and vertical cuts by using signal cancellation, though with potentially higher noise or phase issues compared to a true mono design.

The cartridges in the Featured Products section below are true mono; made at the factory only for mono use. The rest in the Products section are regular stereo cartridges that would need to be wired per above to approximate mono output. This could include shunting the pins at the back of the cartridge per above or you might even try pressing the mono button on your reciever which may effectively parallel the two "binaural" signals.

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78RPM Ready

Moving Magnet 78 RPM Mono Cartridges

Modified Stereo Cartridge (Two Coils Wired Together)

1. Parallel or Series Wiring for Lateral Cuts

2. Series (or Anti-Series) Wiring for (less common) Vertical Cuts

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