MONO cartridge recommendation

Lew, I should have posed it as a question rather than a statement. As in: "Is a mono switch the same as a mono cartridge?" I ask because the stereo pickup creates it’s output signal from both the horizontal (monaural) and vertical (stereo) modulations. When the stereo pickup plays the groove of a mono LP, the signal resulting from the cartridge trying to read a vertical modulation (of which there is none on a mono LP, correct?) contains any noise and/or distortion obtained or created by that attempt---it is now an intrinsic part of the signal. Does putting the Mode switch to it’s mono setting enable the pre to cancel that noise? I don’t know.

A true mono cartridge, in contrast, does not try to create a signal from the vertical modulation to begin with---it is deaf to the noise/distortion created by trying to do so. If it is done perfectly, a mono cartridge should sound the same whether the Mode switch is set to stereo or mono, I would think. Of course, perfection is an unachievable goal!

I posted this, only to see Lew's post directly above it. Never mind!

Lewm, I have an Audio Research LS-1 specifically for it's Mode switch, which offers Stereo/Reverse/Mono/Left/Right from it's main outputs. It's fun to switch between Left and Right on early Stereo LP's, like The Beatles. Vocals on one channel, instruments on the other!

But a mono switch is not the same as a mono cartridge. The mono cartridge senses only the horizontal modulation, ignoring the vertical. The mono switch blends the left and right channels, and a stereo cartridge creates it's signal from both horizontal and vertical modulations. When tracing the grooves of a mono LP, the signal a stereo cartridge creates from the vertical modulation is of only the noise contained therein. It's true that putting your Mode switch to Mono when playing mono LPs with a stereo cartridge reduces groove noise, but how and why? I gotta get me a mono cartridge!

The Decca/London stereo cartridges are unique in having each of it's two coils dedicated to one of the two modulation planes, one for the horizontal, one for the vertical. That's the stereo version; London makes a mono cartridge, which omits the vertical coil. I'd say that's a "from the ground up" mono design!