[lcp12345]

I have completed the building of Dynalo.
I have power up it without the Cap installed since I have not got it at the beginning. The DC offset is around +/-5mV at stable.

But, the DC offset will become around 65mV with the 10pF Cap C27/C28 installed. The DC offset will not drop down.

Hence, I have drop the CAP. Is there any side effect if I do not install this CAP? Also, what is the purpose ot it?

 

[MisterX]

Those caps are there to "correct" a minor overshoot in the square wave response of the amplifier.
Their use should not effect the dc offset of your amplifier.

 

[lcp12345]

Quote:

Originally Posted by MisterX /img/forum/go_quote.gif Those caps are there to "correct" a minor overshoot in the square wave response of the amplifier. Their use should not effect the dc offset of your amplifier.

I don't know why. But, it is really affect the DC offset. Maybe, I will feed a square wave to check the response tomorrow.

 

[Garbz]

I don't use it and the original circuit didn't either. I don't listen to square waves often so I didn't really care about it. It sounds fantastic without it.

 

[Pars]

Those caps limit the bandwidth in the feedback loop slightly (they are in parallel with the feedback 10K resistor IIRC). They should have no effect on DC offset. Did you use one of the group buy Dynalo PCBs for this, or did you build your own (either board or other)? If its the latter, I would suspect something is not connected correctly.

 

[lcp12345]

Quote:

Originally Posted by Pars /img/forum/go_quote.gif Those caps limit the bandwidth in the feedback loop slightly (they are in parallel with the feedback 10K resistor IIRC). They should have no effect on DC offset. Did you use one of the group buy Dynalo PCBs for this, or did you build your own (either board or other)? If its the latter, I would suspect something is not connected correctly.

I am using Rev C from Dan. I don'y understand because I have removed the cap yesterday. The DC offset drop to +/- 5mV. I have observed the square wave output. There is no ringing at all. Hence, I will not install back. BTW, I am buliding a balanced version of it. Is it power enough using only one transformer to provide the regulated DC output to 2 power supplys?