MANY MANY Thanks - now it’s working OK!!!
Another question - quest for me. I bought in China PCB for headphone amplifire A1-HD8-Pro and that amplifire is OK for me - now I use it and DC Offset on headphone jack socket is very small,- ca. 5mV only.
I was trying to create QSPICE simulation.
Before I have had created Lehmann Black Cube amp - and simulation with one single OPA is working OK.
Next, I want to try to rewrite from schematic and PCB, circuit to simulate in Qspice - and receive nothing - I have tested many OPA - not working as I expect - with small signal and big DC Offset in the end.
Have you any idea, why I receive a big DC offset in Qspice simulation? Lehmann simulation is OK, but A1 circuit form schematic I had receive from China and real PCB - something bad. But that headphone amplifire is working on my desk.
I was convinced that it was due to this new Qspice upgrade, but when now the tube schematics work - I have no idea what is wrong in the simulation.
!!!headphone-amp-HD8-A1-PRO.qsch (40.7 KB)
!!!headphone-amp-HD8-A1-PRO-v2.qsch (34.9 KB)
OK-WORKING-headphone-amp-LEHMANN-AUDIO.qsch (25.5 KB)