So... a deepening mystery... Well not really. At this point its trying to figure out a solution if my theory is valid and what to do. 
I'm currently in college, and my dorm was built in 1920something. Not only that, but it was a 1920something hotel in Boston, where the power is known to be notoriously bad.
When listening to music, and the fridge in the room clicks on, my speakers make a hollow sounding pop, which is louder the more volume the speakers are given. The same problem also happens even when the fridge does not click on, but it is much much louder and sounds like that nasty powering-on pop that can blow tweeters. Also, it happens even with the music paused, or the receiver powered off sometimes. And my receiver is a Sherwood S-8900 that, when off, is actually fully powered down. So somehow the 'power pop' (as I am calling it) is able to make its way through the amp even when it has no power. This problem persists whether my laptop is the source or my turntable.
Not only that, but the pop is audible, but less so, when using my headphone amp, a Schiit Magni/Modi setup. So I am pretty sure it is a power issue.
So whats a possible remedy? The whole room is on the same circuit. Adding more capacitance to the power supplies? Or some other filter?
I'm currently in college, and my dorm was built in 1920something. Not only that, but it was a 1920something hotel in Boston, where the power is known to be notoriously bad.
When listening to music, and the fridge in the room clicks on, my speakers make a hollow sounding pop, which is louder the more volume the speakers are given. The same problem also happens even when the fridge does not click on, but it is much much louder and sounds like that nasty powering-on pop that can blow tweeters. Also, it happens even with the music paused, or the receiver powered off sometimes. And my receiver is a Sherwood S-8900 that, when off, is actually fully powered down. So somehow the 'power pop' (as I am calling it) is able to make its way through the amp even when it has no power. This problem persists whether my laptop is the source or my turntable.
Not only that, but the pop is audible, but less so, when using my headphone amp, a Schiit Magni/Modi setup. So I am pretty sure it is a power issue.
So whats a possible remedy? The whole room is on the same circuit. Adding more capacitance to the power supplies? Or some other filter?
I am inclined to assume mains cable conducted interference. I am thinking that there must be some large voltage spike, and this is either passing through the switch or exists on the neutral connection, which is not disconnected from the mains by the power switch, explaining how I am hearing the pop when the receiver is switched off.
the question is how to fix this.
the question is how to fix this.
Mains Filter Question
I clicked through this thread, as well as did some google searching. It would seem as if most of the filter designs out there require that the chassis be grounded.
For my Sherwood, it has just the standard live and neutral connections. The chassis is grounded, but it looks like in the picture. I think there would be issues hooking up a third ground pin in order to ground the chassis as would be required in a proper mains filter, and R175 and R170 might have to be removed. But I would be afraid of what might happen throughout the rest of the circuit if this were done. Would it be an issue if the chassis were not grounded?I think it would potentially be dangerous.
I clicked through this thread, as well as did some google searching. It would seem as if most of the filter designs out there require that the chassis be grounded.
For my Sherwood, it has just the standard live and neutral connections. The chassis is grounded, but it looks like in the picture. I think there would be issues hooking up a third ground pin in order to ground the chassis as would be required in a proper mains filter, and R175 and R170 might have to be removed. But I would be afraid of what might happen throughout the rest of the circuit if this were done. Would it be an issue if the chassis were not grounded?I think it would potentially be dangerous.
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I was thinking about using this circuit, but this requires that the ground connection coming off the circuit be grounded to the chassis of the equipment- something I don't think I could do, referencing the above picture. I was wondering though.... I want to make a power strip or something with the filter to plug the equipment into. If i were to do that, and the power strip were made with a metal chassis, and I were to ground that, wouldn't it be all set to then plug in just two prong equipment? I understand the reasoning for the ground requirement being in case the ground lifts the enclosure won't become charged. Any way I could get this to work?
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I once had trouble with mains powered disco record decks popping through the amplifier when the motor was turned on and off.
I put 100nf 250VAC capacitor across the switch and that fixed it.
When the switch arcs it gives off radiated RF and also passes noise down the mains wires.
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