Ground lift switches on Power Amps

[Guest]

<font color='#000000'>On the back of many power amps I see a switch called &quot;Ground Lift&quot;. Is it safe to use this switch to remove a ground loop hum? Is the amp now in fact no longer grounded?</font>

 

[PaulF]

<font color='#000000'>That's what it's there for so go ahead and use it. If there was no other grounding you would not have a loop. The electronics may receive the ground via the cabling to the other devices. What it probably does is lift the local ground to the electronics but I assume it keeps the chassis grounded for safety.</font>

 

[Guest]

<font color='#000000'>Thanks paul. No one else replied. Is it because a lot of people don't post at this site? Maybe they don't know about it? I was hoping to get more responces.</font>

 

[Rob Babcock]

<font color='#000000'>Isn't one response enough, Joe? Especially if he's correct!

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[Guest]

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Rob Babcock : Isn't one response enough, Joe? Especially if he's correct!

 

I just thought I would get a second opinion. I thought another person might have some additional insight into the subject of using the ground lift switch. I believe that paul knows what he is talking about. Unfortunately, in the world of highend audio there is some much misinformation that is becomes hard to sift the truth from all the myths. I thought that maybe while the ground lift switch might be safe to use there may also be some other problem in using it that was not mentioned by paul. Remember This is audio. Just because the company that made the amp installed the switch, doesn't necessarily mean that is it completely alright to use. While the ground lift switch might be electrically safe it may cause other problems that no one, not even the manufaturer, mentioned. If something happens years latter because the switch was used, the manufacture is not going to care. The product will now be out of warranty and the manufacturer has already made their money from you.</font>

 

[Guest]

<font color='#000000'>Second opinion, I concur with PaulF. &nbsp;I'll even cite specific information. &nbsp;I have several Bryston amps which sport a ground lift switch on the back panel. &nbsp;Indeed, the switch only breaks the chassis ground to audio ground path leaving the chassis still connected to mains ground. &nbsp;This was a problem in my system which required me to STILL use a ground lifting adapter on the AC plug to eliminate hum in my system.</font>

 

[Guest]

<font color='#000000'>How are receivers grounded compaired with separate power amps? Receivers never use three prong plugs on their power cords. If they are grounded differently why don't manufactures use the same grounding system on power amps?</font>