Amplifier Damage
Had a question, can an amplifier's input stages be hurt, driving an audio signal through it while it is in Stand By/Powered down. The reason I am asking is I have two integrated amps hooked up to the DAC, one to the unbalanced out and the other balanced out. The one hooked up to the Unbalanced out was powered down while I was listening to the one hooked up to the balanced out for several hours.
Once I realized that, I disconnected the Amp powered off, Everything seems to work fine, but I had the nagging question. Does the input audio signal get shunted to ground through a diode in the input amp stages when its powered off or something to protect the circuitry?
Any inputs will be great
@cd318 loved reading your response.. The last four sentences are the best and typically I try to lead my life 😊 that way.. too much seriousness would lead to health issues anyways.. Coincidentally, both Amps are Class A.. But again, no damage done.. So I'll move on and enjoy the music.. Thanks again.. |
@holmz the integrated that I had swtiched off(Standby), but connected to the unbalanced out of the Active Luxman D03X DAC is the Luxman 550AXII. The balanced out was connected to the Luxman 595ASE which I was listening to. So I dived into the block diagram of the 550AXII, looks like the input signal goes through several gating switches for Tone control, Subsonic control, goes through a buffer before it hits the multi step ladder circuitry of the volume control. All this is in the path before it sees the Preamp circuit. So I am not sure, how far the audio signal goes through when the Unit is in stand by mode. I might call Luxman tomorrow to get more insight into this.. |
@russ69 Thank you!! it was accidental.. I am usually careful with things like this.. But it was a miss yesterday.. Hopefully it's not a permanent damage.. |
Okay guys, I was just on the phone with Luxman service.. It's all good, every Luxman component has relays in the Input and Output stages. That's the clicking sound that you hear when you select and deselect input and output options. So when the 550AXII is in stand by mode, the input relays are disconnected. So what ever signal I presented at the input is not passed through. And the D03X is designed to be active for both Unbalanced and balanced output at the same time. They suggested I could experiment turning on and off one of the equipment to see if it makes any difference in the sound of the one still connected. Although, they said it is safe to try that.. I am not venturing that route.. When I get the C900U in a couple of weeks, I'll have these separate setups.. Hope that helps.. |
@carlsbad it's close.. In my setup, what happened was, I had the unit that was in stand by connected and being fed with the audio signal. However, the internal relay switch of the Standby unit is automatically disengaged to not let the signal go through.. Yes!! it's very similar to your setup.. |
