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Old 05-16-2014, 01:29 PM
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DavGoodlin DavGoodlin is offline
Motorola Minion
 
Join Date: Aug 2011
Location: near Strasburg PA
Posts: 3,410
The way I understand cartridges, there are three major types;

1-crystal cartridge has the highest output, about 3 volts, rated at 80 Kilohms (1kHz) and was often used with only a pentode output tube and no pre-amp stage. 10g of tracking is needed to get that kind of output and they were physically unstable, usually needing rebuilding or crafting a replacement with a ceramic cartridge.

2-ceramic cartridge has a lower output, 0.5-1 volt and lower impedance, 47K and feeds into a triode pre-amp before the beam power pentode amp. Tracking force is still up there at 4-8g, with more expensive 2g tracking versions like the Sonotone 8T, with a lower .3 volt output, requiring a matching network as Olorin67 notes. sometimes, adding a 10K resistor across the output to match a mag phono input's impedance will improve fidelity at higher frequencies.

3-magnetic cartridge has a very low output, about .006 volts, lowest impedance at 10K and requires an additional, very low-noise stage of amplification. These are rarely found on old record players, but are common on turntables of the 70s and later.

References: RCA 1938-42 Phonograph service book, Wiki under 'Phonographs' and "Voice of Music Enthusiasts" cartridge data
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Last edited by DavGoodlin; 05-16-2014 at 01:58 PM.
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