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[email protected] tabbypurr@gmail.com is offline
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Default Whats the difference between Magnetic & Crystal headphones?

On Friday, 28 December 2018 06:04:14 UTC, whit3rd wrote:
On Thursday, December 27, 2018 at 7:12:00 PM UTC-8, wrote:


Whats the difference between Magnetic & Crystal headphones?

Magnetic headphones (like most earbuds) are low-impedance and have DC
conductivity. Crystal headphones are high impedance (and are capacitive,
kind of like a capacitor microphone in reverse), so have NO DC conductivity.
The likely reason to use magnetic is that a DC path to ground is required
to correctly bias some amplifier stage.

Absent a DC path to ground, some tube-type equipment outputs hundreds of
volts, could be hazardous.


Moving iron headphones were originally in the 1-8k ohm range, modern ones mostly 32 ohms. Crystals are odrers of magnitude higher impedance, much greater efficiency & dire sound quality. A DC path can be added using a resistor or choke.


NT