Ground connection?

[gbhsi1]

Sorry if this might seem like a stupid question but why does one need to connect the ground wire from the amp to the turntable? I have always done this but last night after some cleaning the wire broke as it was a tight fit. This morning without remembering what I did to the wire I played a record and it all sounded fine without the ground connection??? why is that?

 

[gbhsi1]

ermm, just realised the humming noise- knew it was a stupid question!!! 🙂

 

[Anonymous]

Not a stupid question at all... In my book there is no such thing as stupid questions, only stupid answers. And anyway, you cannot be born with knowledge of everything you need to know in your whole life. You gotta ask at some point...

Anyway, yes, you found out, the humming... Basically if you do not connect earth of your turntable to your amp, you will get a floating earth, due to separate power supplies for turn table and amp.In addition, the signal levels for turn tables are extremely low. Way lower than the signal levels from a CD or DVD player (we are talking hundred fold-ish). Such small signals are very sensitive to external influences, like mobile phones, but also power supplies, and even other signal lines. Grounding your turntable makes it a little more robust to external influences.

This can have an effect on your sound (humming). Earthing is in fact quite important for traditional/analogue audio. Tube amps need to be earthed as well (to mains earth), but with primary reason being hum, an important secondary reason for tube amps is safety. Tubes use high voltages, which are lethal, much higher than mains. Hence earthing is important.

Earthing is in fact quite tricky to get right. There is a whole science around it, and I know barely the basics, so won't go into too much detail.

 

[gbhsi1]

ksporry:
Not a stupid question at all... In my book there is no such thing as stupid questions, only stupid answers. And anyway, you cannot be born with knowledge of everything you need to know in your whole life. You gotta ask at some point...

Anyway, yes, you found out, the humming... Basically if you do not connect earth of your turntable to your amp, you will get a floating earth, due to separate power supplies for turn table and amp.In addition, the signal levels for turn tables are extremely low. Way lower than the signal levels from a CD or DVD player (we are talking hundred fold-ish). Such small signals are very sensitive to external influences, like mobile phones, but also power supplies, and even other signal lines. Grounding your turntable makes it a little more robust to external influences.

This can have an effect on your sound (humming). Earthing is in fact quite important for traditional/analogue audio. Tube amps need to be earthed as well (to mains earth), but with primary reason being hum, an important secondary reason for tube amps is safety. Tubes use high voltages, which are lethal, much higher than mains. Hence earthing is important.

Earthing is in fact quite tricky to get right. There is a whole science around it, and I know barely the basics, so won't go into too much detail.

Thanks for the reply, it has been very informative 🙂