Tube amp acting very strange-- tubes acting as speakers?
I have a 100 watt tube amp and it did something very strange today.
I noticed that when I disconnected the speaker cable from the speaker output jack and I still had music playing on a line in into the amp, the amp still played music, but it sounded like the music was coming from the tubes!
When I turned up the pre amp gain and the power gain up all the way and my music player gain up all the way, the tubes are playing music that fills the room with sound like a speaker!
Then after 10 minutes of studying this phenomenon I smelt smoke and immediately disconnected everything and turned the amp off. I hope I didn't break anything.
I don't think tubes are supposed to do this. I've got a dynamic mic to play music, but that is less far fetched than tubes playing music.
Perhaps the output transformer is what is doing the music playing like if I connect a dyamic mic to an audio source the dynamic mic will make sound?
That doesn't make any sense that the output transformer would be making sound, because there is no membrane for it to vibrate.
I had my ear against the output transformer and all the sound seemed to be coming from the glowing hot tubes, not the output transformer.
Does this indicate a short of the output transformer shorting to a power tube and the power tube glass with the help of the Edison effect is acting as the speaker membrane?
When I disconnect the audio source, I still hear sound, just I hear static, and when I hold the input cable in the right place it even occassionally picks up morse code even though there is no mixer connected! Shorted power tube acting as a non linear device?
I have a 100 watt tube amp and it did something very strange today.
I noticed that when I disconnected the speaker cable from the speaker output jack and I still had music playing on a line in into the amp, the amp still played music, but it sounded like the music was coming from the tubes!
When I turned up the pre amp gain and the power gain up all the way and my music player gain up all the way, the tubes are playing music that fills the room with sound like a speaker!
Then after 10 minutes of studying this phenomenon I smelt smoke and immediately disconnected everything and turned the amp off. I hope I didn't break anything.
I don't think tubes are supposed to do this. I've got a dynamic mic to play music, but that is less far fetched than tubes playing music.
Perhaps the output transformer is what is doing the music playing like if I connect a dyamic mic to an audio source the dynamic mic will make sound?
That doesn't make any sense that the output transformer would be making sound, because there is no membrane for it to vibrate.
I had my ear against the output transformer and all the sound seemed to be coming from the glowing hot tubes, not the output transformer.
Does this indicate a short of the output transformer shorting to a power tube and the power tube glass with the help of the Edison effect is acting as the speaker membrane?
When I disconnect the audio source, I still hear sound, just I hear static, and when I hold the input cable in the right place it even occassionally picks up morse code even though there is no mixer connected! Shorted power tube acting as a non linear device?
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