How often do you demagnitize your MC cartridge?

I demagnetize my Lyra Helikon, occasionally (every 6 months or so). The improvements are noticeable. It is also recommended by the manufacturer.

For those who have not tried it, how can you be so certain that it will have negative effects? I have demagnetized many MC cartridges over the years without any negative side effects.

Rockinroni:

I am using the Audioquest battery operated demagnetizer (it was about $70). I have not used the sweep LP, so I cannot provide any first hand information.

It so happens that the manufacturers of the lyra cartridges are "engineers". They recommend demagnetizing of MC cartridges periodically. I do mine at most twice per year.

In any event, I am basing my statements on observations not "hear-say" as some would have it.

Marakanetz, since you are throwing stones: it might serve you well to look at your initial contribution to this thread. It is certainly not in keeping with what an "engineer" would write. Statement such as "The cartridge normally must be magnetized...." is trite at best.

"A little knowledge is some times quite dangerous" so says the old adage. “Fellas”, we are taking about traces of residual magnetization in the coils. So called “pure Copper” coils may have traces of iron or other magnetic materials. After prolonged usage the trace molecules will align themselves into magnetic domains. The net effect is a perturbation of the magnetic field intensity created by the fixed magnets at the position of the coil (the resulting field is the vector sum of the field from the magnetic dipoles in the coil and the field from the fixed magnet). Demagnetization attempts to make the orientation of the dipoles random thus rendering the coil un-magnetized (the sum of the B field is zero, because the random orientation of the magnetic dipoles leads to cancellation.)

I agree that frequent demagnetization may be detrimental to the cartridge. However, I feel strongly, that many cartridges benefit from periodic demagnetization.