Koetsu cartridges. They must be something special.

Jason, I just read the long piece on "pickups" in Wikipedia.  Seems there are a few different types and they operate in a few different ways, any set of which could affect the recorded signal in one way or another.  So I would guess it is about as difficult to say what the type of magnet does to the sound from a pickup as it is to say how the magnetic material of a phono cartridge affects its sound.  I am not saying there is no effect; I am only wondering how one would know or how to investigate that effect as an isolated factor.

This just in: platinum is not magnetic. The platinum in cartridge magnets is probably an alloy of Pt and Co, somewhat akin to Alnico (aluminum/nickel/cobalt) where both Co and Ni are magnetic.

Yo-yo, so you’ve compared two kinds of magnet set up identically in terms of geometry and field strength and whatever other parameters pertain and compared them on the same Strat ( important to use the same guitar both ways)? And listeners agree the sound is different? (Not to mention we’re talking about a guitar pickup not a cartridge.) even if it’s been done, that doesn’t explain a mechanism.

But I refuse to believe a magnet has a "sound". The magnet has an effect determined by its properties as a magnet in combination with the properties of the coils and its mass (of the magnet). The coil does not know it is being affected by a platinum magnet; it only knows the strength of the magnetic field surrounding it. I know there are mystiques surrounding the use of samarium cobalt or platinum or neodynium or other magnetizable metals (alnico?) in MC cartridges, but what is the possible mechanism, other than the above, mass, field strength, and geometry (meaning how the magnet and coil are placed in space)? Can someone ’splain me? Anyway, Koetsu cartridges are a matter of taste, as is the choice of any cartridge brand. They used to be characterized as warm and "musical" or rich sounding but some said of the Rosewood series that they were lacking in low bass and high treble. The Rosewood Signature Platinum was said to have corrected that issue with bass and treble, at the expense of having a much lower signal voltage output; I never heard one. Then came later wood bodied models like the various Urushi models and still later the stone bodied models, among which there are additional sonic differences. I have an Urushi and like it very much, but maybe it is not my very favorite LOMC cartridge. Nevertheless it is definitely not lacking in bass and treble response. I’d like to own a stone-bodied model but was unwilling to fork over the moolah. I own about 6-7 other LOMC cartridges, so the Urushi is just one in my stable. Anyway, it is impossible to disagree with Inna when he writes, "It seems that quite a number of Audiogoners have Koetsu, or a few of them." That sentence has its own escape clause.