TEAC PE-505 Phonostage demagnetization function???


The new TEAC Phonostage PE-505 has a cartridge demagnetization function.

"DEMAG function to refresh the cartridges

With the quick demagnetize function, both magnetized iron cores of MC cartridges and the step-up transformer are demagnetized by playing back a vinyl record for as short as 30 seconds with the DEMAG position."

I have a hard time figuring out what that is supposed to do. 

- The permanent magnets in MM or MC design should certainly not be changed in magnetization. Newer designs also use neodymium magnets (e.g. Rega).

- Copper (or silver) wire cannot be magnetized, neither boron (or other cantilever material) and sapphire/diamond.

Am I missing something, or is this demagnetization function nothing but a pointless gimmick? Demag on tape machines for sure. Also on non-permanent magnets (e.g. electron microscope optics), absolutely. But on cartridges with permanent magnets?

And on SUTs, don't see it either as the signal is constantly changing and at very low power, so essentially playing anything through the SUT will constantly neutralize whatever has come before. On EM's it is different, because on stigmation coils the adjustment current is continuous, so over time, iron cores can become slightly permanently magnetized. 

oberoniaomnia

The Process Demagnetizes the Structure the coils are formed on.

The process can also be referred to as Degauss.

I am familiar with this from experiencing the Phasemation Degauss used on MC Carts. If one wants to extract the very last morsel from their MC Cart', listening after the degauss, does present an audible difference, one might say is perceivable as a tidied up end sonic.       

The coils are typically made from copper wire, and Cu-metal cannot be permanently magnetized. That is physics/material science.

Yes, degauss = demagnetize, but still does not address what can possibly get magnetized in a phono cartridge. The question remains, is this demagnetization/degauss button a function addressing a non-existent problem? Is the whole thing just a pointless gimmick? I still don't see what could possibly get magnetized and be in need of demagnetization.

It is not designed to do anything to the copper wire.  It is the structure that the wire is coiled upon in some cartridge designs such as iron or permalloy that can pick up some magnetization.  Other constructions like the Benz Micro Ruby use an actual ruby for this so degaussing obviously would be of no value.  This is strictly for Moving Coil cartridges and only those with a permalloy or iron former.  

@drrsutliff Thanks for this. That makes slightly more sense. 

I still have trouble to see how such a former can be permanently magnetized with constantly changing voltages going through coils. Doing a voltage sweep IS a demagnetization procedure. So normal use of a cart will constantly demag/degauss  any cartridge. 

Or is the assumption that the fixed magnets in a MC cart will magnetize the formers? Even then, the constantly changing voltages in the coil will demag/degauss the former. And running massive voltages/currents through the fine wires (18 µm in my Rega Aphelion 2) is certainly not desirable either. 

If this is a real issue, I wonder why an engineering-driven company like Rega (vibration measuring machine) is using an iron cross and coil assembly on their flagship cart. They use ceramic bearings, carbon fibre in plinth, W-counterweight, so no strangers to exotic materials.

And I bet there are neither measurements nor audio sample files to support any of this. At least I have not seen any.

Thanks y'all for humoring my curiosity.