If you use a cheater plug, or disconnect the ground in the preamp, it will not be considered grounded. There is always a possibility of some kind of failure happening. With a preamp, the power switch alone is a risk. Lose connection somewhere in it too.
With the power switch off and on cycles, the plastic housing to the power switch itself can fail. Also, if the plastic housing fails, it can let the 120 volt energized contact touch the preamp housing. That of course can let the 120 volts energize the whole preamp cabinet. The 120 volt wire feeding the switch could break off, and contact the cabinet, energizing it.
That switch failure alone, happens often in all kinds of electrical products, besides home audio. When it happens nowadays, it usually trips the breaker, due to the ground.
I think grounded outlets became part of the electrical code
in 1951. This was done to save our lives. Yes I know, it can help make headaches with ground loop hum problems.
These cheater plugs are now banned in parts of Canada.
People still die from electrocution as seen here
Wikipedia has an article about them here.
Here is a news article about children swimming getting electrocuted (I had to shut off my ad block to read it). If it had the proper ground, they'd probably still be alive.
So yes, there is a risk.
With the power switch off and on cycles, the plastic housing to the power switch itself can fail. Also, if the plastic housing fails, it can let the 120 volt energized contact touch the preamp housing. That of course can let the 120 volts energize the whole preamp cabinet. The 120 volt wire feeding the switch could break off, and contact the cabinet, energizing it.
That switch failure alone, happens often in all kinds of electrical products, besides home audio. When it happens nowadays, it usually trips the breaker, due to the ground.
I think grounded outlets became part of the electrical code
in 1951. This was done to save our lives. Yes I know, it can help make headaches with ground loop hum problems.
These cheater plugs are now banned in parts of Canada.
People still die from electrocution as seen here
Wikipedia has an article about them here.
Here is a news article about children swimming getting electrocuted (I had to shut off my ad block to read it). If it had the proper ground, they'd probably still be alive.
So yes, there is a risk.