Grounding problem with Lepai Class-T amp, please help.

Quote:

Originally Posted by PascLeRasc 

(X-posted from headphone amps)

I really like my new Lepai Tripath Class-T amp (http://amzn.to/W9fPmF) but it produces a high pitched whine that really ruins it. When I touch the outside box it somewhat decreases. This makes me think it needs to be grounded. It takes a 12V adapter. Is there one that will ground it? I know a little about electronics, how could I ground it myself?
Thanks!

I do not know if my HUM ground noise is the same with your problem or not but I own a few of the Lepai 2020+ and I am very happy with its SQ and build until I found out that they have ground hum.

At first 2 of my Lepai 2020+ produce a loud ground hum starting from 9 o' clock on the volume pot. These 2 amps were plugged into an expensive Monster surge protector along with other devices such as desktop, CD Players, Ipod Dock speakers...I was very disappointed and I determined that the problem had to be the poor QC of the Lepai 2020+ but when I disconnected the Lepai 2020+ power supply ( provided ) and I connected the Lepai 2020+ amps to a separated surge protection ( less expensive ACP products), miracle happened, no ground hum noise even when I put my ears closed to the speakers. I cannot be any happier right now with my Lepai 2020+ purchases.

I am not electrician so I cannot tell you why but there must be some interference among different devices that are hooked up to the same surge protector.

The PS provided does not contain an "earth" only pos/neg . Any earth therefore must come via the channel inputs. Its possible there are more than one "ground loop" -in other words -more than one earth return.If acdoans advice doesnt work check how many earths are provided by the preceding audio-equipment and if more than one -remove one earth connection at a time and try it.
 

Standard troubleshooting procedure:

a] Unplug any and all cables.

b] Connect power supply to the wall receptacle and speakers.

c] Turn-on.  Does it hum? does it whine? how about when you touch it?

d] If not, use a battery powered music source.

e] If still no hum, try a single AC powered music source. Connect it to the same AC outlet (no surge protectors  or power conditioners) and a plain-jane co-ax interconnect.