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i was wondering how PC know which speaker I plugged in? When I plug in standard pc speaker, my pc says that speaker is connected. If I plug in headphones, PC says that headphones are connected. Does speakers/headphones has some kind of memory to store information, or what? I mean, speaker device can't send digital information throught 3.5mm jack (right?), so there must be some kind of analog information to send (beside the sound itslef). I am not familiar with electronics so I am sorry if question is stupid. Thank you.
stfnsn
Posted 2018-08-26T22:26:22.803
Reputation: 11
2A guess: headphones are low-impedance (8 Ω -100 Ω), and speakers are medium-impedance (1,000 Ωor higher). You could test this by putting a 10 Ω resistor across the speaker input to see if it shows as 'phones. – DrMoishe Pippik – 2018-08-26T22:33:42.173
1Exactly as @DrMoishePippik said - by impedance. There is no memory and jack is a completely analog interface. The impedance is compared by the DAC/ADC integrated circuit on the motherboard. – Hardoman – 2018-08-26T23:05:03.783
What are you and @DrMoishePippik referring to as "standard pc speaker"? The impedance of (passive) "speakers" can be anywhere from 3 Ohms on up. Active speakers (aka powered speakers) have an input impedance much higher (e.g. 10KOhm) since it's the input of an amplifier (rather than a passive load)). – sawdust – 2018-08-27T00:12:57.940
@sawdust, true, by "standard PC", I mean "powered", with an internal amplifier. However, some powered speakers intentionally have a lower input impedance than 10 kΩ to better suit output requirements of the PC audio amp. I've had to add parallel resistance to prevent excessive bass emphasis, where there was a poor match. – DrMoishe Pippik – 2018-08-27T01:37:19.987