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A Ghost in the System? Music Thru Speakers with Preamp Disconnected

I disconnected my preamp yesterday completely from my system in order to install some constrained layer damping tape.  The DAC was on and receiving music, but the signal chain between the power amp and the dac was completely broken due to the preamp being removed.  BUT:  I could hear very low volume, but very clear, music playing thru the speakers!  And no, I was not intoxicated.  How is this possible?  Cool stuff.  Thanks.
tomask6
twoleftears's avatar
twoleftears
5,318 posts
 
Question #1: did the music audible through the speakers match the music being received by the DAC?  Whether or not it was the same will affect the diagnostic.
mofimadness's avatar
mofimadness
4,992 posts
 
Were you hearing the same music that was on the DAC?  If not, probably RF interference from a local radio station.

erik_squires
16,121 posts
 
By disconnected, do you mean you removed the interconnect cables?

If yes, then power issue. If not, you are getting crosstalk from the preamp, though it is usually thought of as a Left to Right thing, it's also possible to get it from one input pair to another.
douglas_schroeder
3,281 posts
 
This can only be Phantom Doppler Effect. You are moving so quickly that the sound is only catching up after you disconnected... 
geoffkait's avatar
geoffkait
23,365 posts
 
Electrons move very slowing. So, after you pull the plug they’re already on the way. They just take a while to get there. 
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