Mono cartridge classification

Hey sorry I'm late to the party.

The Ortofon CG 25 DI MKII and CG 65 cartridges are SPU-styled (although SPU technically stands for Stereo Pick Up). Some places refer to these as MPU cartridges (M meaning 'Mono').

The CG 25 has a 25 micrometer diameter conical diamond, and the 65... Well, 65 micrometer. 25um is best for your general mono/microgroove recordings whereas 65 is for 78rpm recordings. These are TRUE mono designs built as closely to the original mono cartridges from the 1950s/60s. The SPU Mono GM MKII, by contrast, is a strapped design - it's a stereo cartridge wired to run in mono.

Yes, Lyra has some very interesting diamond profiles, and for some people this will be the ticket to high performance reproduction of mono recordings.

Ortofon feels that the CG25 and CG65 represent the true artisan style of playback of mono recordings, and consequently these cartridges find their way primarily in modern-vintage systems with removable-headshell-style tonearms. Your Thorens, Garrard, etc crowd. You might not get a highly detailed listen, but mind you these cartridges are designed to provide everything but the HiFi sort of sound. They're meant to provide body, rich and syrupy midrange, and slam.

Depends what you like... Lyra also makes a stellar product.

I work for Ortofon.

CG25 and CG65 are the only true mono models that Ortofon makes, and they have no vertical compliance whatsoever. In theory, a spin on a stereo record would not have positive consequences for the vinyl.

In the SPU Mono GM MKII, not only is it a high output moving coil with suggested loading of 47k (3mV output at 5cm/sec). The coil assembly is rotated 45 degrees so that only lateral motion is sensed.

Why they have done this rather than making a true mono design... Not sure. But for the true mono heads who want the cartridge to be made the same as it was back in 1948, the CG 25 and CG 65 should satisfy you. We even sell a dedicated trafo for them.

I work for Ortofon