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Swiftie
2015-07-31, 08:10
My AKG K451 headphones have a documented impedance of 32 Ohms.

Will a Duet player be comfortable with such a load on its RCA/Phono output sockets, or should I interpose a headphone amplifier? I'm proposing to use this setup purely to verify that a new Duet system is fully functional.

In the past, I've used Sennheiser EH 1430 headphones (also 32 Ohms) to verify that the player is actually playing, but I'm now concerned that I might damage the player, and there's not an inexhaustible supply...

Julf
2015-07-31, 08:16
My AKG K451 headphones have a documented impedance of 32 Ohms.

Will a Duet player be comfortable with such a load, or should I interpose a headphone amplifier? I'm proposing to use this setup purely to verify that a new Duet system is fully functional.

In the past, I've used Sennheiser EH 1430 headphones (also 32 Ohms) to verify that the player is actually playing, but I'm now concerned that I might damage the player, and there's not an inexhaustible supply...

I am pretty sure there is enough of series resistance to limit the current so you wouldn't damage the Duet outputs even if you shorted them - sound quality is another story.

Swiftie
2015-07-31, 22:29
I am pretty sure there is enough of series resistance to limit the current so you wouldn't damage the Duet outputs even if you shorted them - sound quality is another story.
Thanks for your comforting reply.

I recall reading a review of a 1kW HiFi amplifier which claimed output short circuit protection. So the reviewer turned it up to max volume then stuck a 6" nail across the speaker terminals.
The result? "Large, frightening sparks, but no damage". I still use the phrase "large, frightening sparks" whenever the opportunity arises.

I must have taken this to heart, as later on in life I was requested to build an amplifier that would turn a 1 microvolt signal into 1V peak to peak. The circuit I came up with had such a huge series resistance on the input that you could connect my little amplifier across the 240VAC mains without damage. I tried it. It worked. With some large, frightening clipping, though.

Julf
2015-08-03, 07:34
I recall reading a review of a 1kW HiFi amplifier which claimed output short circuit protection. So the reviewer turned it up to max volume then stuck a 6" nail across the speaker terminals.
The result? "Large, frightening sparks, but no damage". I still use the phrase "large, frightening sparks" whenever the opportunity arises.

Well, any self-respecting power amp should be usable as a welding transformer :)


I must have taken this to heart, as later on in life I was requested to build an amplifier that would turn a 1 microvolt signal into 1V peak to peak. The circuit I came up with had such a huge series resistance on the input that you could connect my little amplifier across the 240VAC mains without damage. I tried it. It worked. With some large, frightening clipping, though.

"Kids, don't try this at home!" :)