Have you heard about polarity of Power Cable?

[cyber_cat]

Hi, Sorry for posting so late, seemed to have missed the post.

if earth is open or polarity is wrong, the sound would be sharp and unnatural.

This was the symptom which I was facing. I suspected this to be due to polarity mismatch between the SMs. Treble was shrill, bass guitars sounded hollow.

Good News!

Could you explain little more.

Cheers!

Chang

Then, I went ahead measured ACV between the amp chassis and input.

I got 2.2~ V as is and after power cable reversal 2.1~ V with DMM (seem to have forgotten the exact values, but I went with the lower ones). I then inverted the power cables each for the lowest values.

Now, the shrillness has gone, bass is fuller, snares are clearer, I can hear the bass guitar notes more clearly. Also, I can push my volume a lot more further.

Dont know if they will make a difference in other systems, but since I had this problem, this method has definitely helped me.

Cheers.

 

[Fantastic]

... I am bit worried about this leak current.

Your solution is correct. Use a dummy 3 pin plug and connect the Earth pin ( largest pin ) with a reasonably good cable to the chassis of any one of your equipment. You can get 'earthing wire' from an electrical store. This is nothing but plain naked copper wire. It doesn't have to be very thick.

But if all you equipment is two pin , why not check the polarity of each. Disconnect all of them . Start with one and see if you 'feel' the leakage. Then add another one and check again. When the offending one is connected the system will 'tingle' you again. Reverse it's power plug and see if it goes away. If not, you will need the Earth connection. Remember to check with every piece of equipment even if one in between is found sensitive to plug polarity.

IN ANY CASE you still need to connect any one piece of equipment to your Earth pin on your supply. It will protect you from shock in case something breaks down.

 

[tiger0691]

Hi, Sorry for posting so late, seemed to have missed the post.



This was the symptom which I was facing. I suspected this to be due to polarity mismatch between the SMs. Treble was shrill, bass guitars sounded hollow.



Then, I went ahead measured ACV between the amp chassis and input.

I got 2.2~ V as is and after power cable reversal 2.1~ V with DMM (seem to have forgotten the exact values, but I went with the lower ones). I then inverted the power cables each for the lowest values.

Now, the shrillness has gone, bass is fuller, snares are clearer, I can hear the bass guitar notes more clearly. Also, I can push my volume a lot more further.

Dont know if they will make a difference in other systems, but since I had this problem, this method has definitely helped me.

Cheers.

It good to see the fine result in your case.
My concern is polarity rather than earthing.
Cheers!

Chang