"The Red3 uses a four piece OTL cantilever that has a Grado specific diamond mounted on a brass bushing.

What's the difference between Blue3 and Red3?
Approximately 15% of the Blue3 production run meet higher specifications. These are hand selected from the batch and designated as Red3.

Grado’s OTL, or optimized transmission line, technology provides an ideal transfer of signal from the surface of the LP to the generator of the system. This technology rejects unwanted resonances and lowers distortion preserving the fundamental and harmonic frequencies of the music. This also helps keep noise generated by the motor system in the cartridge to a minimum.

Grado’s OTL stylus/cantilever design makes records sound quieter, improves the height, width, and depth of the soundstage, and present more detail than previously obtainable.

The Red3 is hand assembled by Grado's team in Brooklyn, with some builders having over 25 years of experience. This updated series of cartridges offers excellent tonal balance, dynamics, and realism, for a most rewarding reproduction of vocals and instruments. The coil winding techniques using ultra high purity copper wire, which were honed during the development of the Lineage Series, have let the electrical circuits achieve unison between the four coils in each phono cartridge. This allows for a precise balance between channels and accurate stereo imaging.
As in all Grado phono cartridges the Red3 is powered by a twin magnet system that optimizes the balance between stereo channels. All internal magnetic circuit parts are held to extremely high tolerances creating the desired stereo imaging. Grado’s patented Flux-Bridger design allows the Red2 to have one of the lowest effective moving mass generating systems while creating an excellent balance throughout the full frequency range."