Helikon LOADING

Nil, the 25x rule emerged from experience and experiment and also compiling data from those (few) cartridge manufacturers who actually publish optimum load values for their products (like van den Hul).

Anyway after compiling a lot of data (on normal output MC cartridges that is) and comparing it with various internal resistance figures, the multiple always seemed to come out at or near 25. To save time, since most cartridge maker's load specs are so vague, it seemed like starting with a value around 25X the internal resistance would put you at or very near the goal; instead of stabbing all over the place from 5 to 47K ohms!

Dear friends: The cartridge load impedadce is a subject of vital importance. It does not have to do nothing with what audio system we have, it is not matters what sound we like, it is not system dependent in any way and it is not a subjective choice.

The right cartridge load impedance is that where the cartridge frequency response is flat, period.
If you like it/or not that load impedance with the sound from the cartridge it is another subject that has nothing to do with the right/correct cartridge load impedance.
The load impedance is not an " equalizer ", the load impedance is an electrical characteristic inherent to cartridges, again, where its frequency responce is flat.
To say another thing/history/thinks/believes , is not valid.

I always ask directly to the manufacturer which is the right load impedance for their cartridges: I don't ask which one like them but which one is the correct impedance.

Examples, Van denhul told me that my Colibri must be running at 540 Ohms and Allaerts told me that my MC2 Finish at 845 Ohms, these impedance values are strictly the value where those cartridges perform flat.

If any one of you are running your cartridges way out of the correct manufacturer load impedance recomendation, then you really don't know how perform your cartridge: what you are hearing is only something near the real cartridge sound reproduction. Now, if with the right/correct cartridge load impedance you don't like the sound reproduction then you have to look around your system where could be a problem, where something is out of synergy but not change the cartridge load impedance hidding/cover with this the real problems all over your system. Be very carefull about.

Of course, you can use the load impedance that you want but that's does not means that is the right way.

Regards and enjoy the music.
Raul.

Dear Neil: Thx for your approval about my post.

Btw, " should point out that cartridges are really current producing devices, but there are very few current amplifying phono preamps, " ,

well I don't know any out there. Our phonopreamp design is a CURRENT one.

Regards and enjoy the music.
Raul.

Raul, I did not realize your new phono pre was a "current" device. I think that is wonderful. I did see another one recently, and if I can find it again ;~)) I will send you the link.

N

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