The 'tube-transistor' enigma by MC carts?


By accident I got to know an guy from Swizerland who has
worked for years as technician (R&D,testing,manuf.etc) by
Benz. I made some joke about 'Zelle',the expresion he used
to refer to carts,by asking if the carts are made by
prisoners? ('zelle' is 'the box' in the prison) He appreciated my joke and explaned to me in 2 sentences
something I never thought about. There are 2 kinds of
'bobins': iron and the other kind. The 'classical example'
of 'iron' is the Ortofon SPU. The advantage: stronger signal and some kind of 'pleasing warm sound.the disadvantage:(more)distortion.
The 'ruby-cross' bobin has (much?) less distortion but can
sound 'thin' depending on the rest of 'the chain'.
This is obviously the so-called 'Holistic' approach ;
aka Rauls 'it depends...'. Me? Because I can't cope with
more then 2 variables at the same time I am for 'simplicity' approch. The best 'definition' of this
approch is from O.Wilde:'I have the simplest tastes. I am
alwys satisfid with the best'. So I am still seaching.
Raul will you please bring (more) light to this issue?


Cheers
128x128nandric
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@bimasta Here is some info translated from Japanese about Air Core Coil of Fidelity-Research PMC-3 :

" Air core coil is adopted as coil, weighing is realized compared to ordinary coil part made of magnetic material as core material, and magnetostriction caused by hysteresis curve of core material is expelled. In addition, by adopting a new special lightweight resin coil bobbin, the total weight of the oscillator is reduced to about 1/3, and the tracking ability is improved.... Samarium cobalt magnet is adopted as a magnetic circuit. This material has an ideal characteristic that it has higher holding power compared with ordinary Alnico type and it is hard to self-demagnetize. Moreover, the yoke part can also be downsized, the cartridge’s own weight is drastically reduced, and the initial characteristics can be kept for a long time.... Precision cutting is applied to the yoke to make the entire magnetic circuit close to a circular shape. As a result, effective magnetic path length can be shortened, size can be reduced, and magnetic flux leakage at the corner portion is reduced to achieve high efficiency.... A 0.04 mm diameter net flow line is adopted as the coil. "
The trade off with an air core versus an iron core or other variant is that you need more turns of wire to achieve the same energy out. So this adds resistance.
Dear @bimasta: Always exist trade-offs. I'm not  cartridge designer but maybe the best is to build cartridge coreless and yoke-less like the Yamaha X-1s. I own it and is truly good performer even that's a vintage one.

R.
@chakster — Thanks, I think I have that text in the booklet that came with it. But a question...
" Air core coil is adopted as coil.... In addition, by adopting a new special lightweight resin coil bobbin...
It seems "core" and "bobbin" are different things. I thought both referred refer to whatever the wire is wound around, i.e. a single thing — apparently not. So now I don’t know what an "air" core is. Can someone educate me, and explain the difference between core, bobbin, armature?

@lewm — More resistance would lower the output, yes? But we’re dealing with low output anyway. Would it have any other significant effects?