GC very low DC offset

[matjans]

After finishing building my gainclone I found that the DC offset on the speaker terminals is about 1 mv . I tested this with three different multimeters (I couldn't believe it, actually ).

Am I just lucky or does anybody else have the same experience?

It sounds pretty nice btw.

 

[roncla]

Yep, on my config on the inverted GC i run a 500k multi turn pot from pin 7 to ground. After running for about 1 hr. i just tune the offset to 0.I have found it sometimes will drift to 1mv , but hay thats acceptable. LOL
ron

 

[king30]

quick question on the pot hookup. The wiper gets hooked to pin seven, and another leg to ground. my pots have three legs. Where does the 3rd one get hooked to?

 

[JCoffey]

Hehe, you said 3rd leg.............

Sorry, I'm in a wierd mood today, and i couldnt pass that one up....

 

[king30]

Ok back to the question. Do I just let it hang 😉 or does it need to be tied somewhere 😉

 

[roncla]

Let it hang LOL!!!! No tie the 2 legs together then to ground.Let the amp come up to normal operating temp, i go about 1 hr. then adjust the pot to provide for 0 v offset.
ron

 

[roncla]

Sorry if there was any confusion (i should read the question). The first leg of the pot goes to pin 7, the next 2 legs (middle one and the outer one) goes to ground.Let the amp run for around 1 hr to come up to full operating temp then adjust the offset to 0 mv.
ron

 

[king30]

ron,
Thanks. That's exactly what I needed.