[IMGDEAD]http://my.tele2.ee/hifi/front_end_idea.gif[/IMGDEAD]
I have been playing around with this basic idea. In theory (at least in my head) the dif amps connected this way would have good current balance without using current mirrors on their collector loads nor the resistors that are not equal. The thing works in SPICE simulation, but I also constructed it in real life and seem to have a lot of problems. The currents are not equal even if I remove the VA stage transistors.....
My question mostly is, if anyone has tried such layout or what thoughts does it provoke in your head. For some reason the idea is attractive to me but as I don't have that much of experience, might be I'm totally overlooking some possible problems..
Ergo
I have been playing around with this basic idea. In theory (at least in my head) the dif amps connected this way would have good current balance without using current mirrors on their collector loads nor the resistors that are not equal. The thing works in SPICE simulation, but I also constructed it in real life and seem to have a lot of problems. The currents are not equal even if I remove the VA stage transistors.....
My question mostly is, if anyone has tried such layout or what thoughts does it provoke in your head. For some reason the idea is attractive to me but as I don't have that much of experience, might be I'm totally overlooking some possible problems..
Ergo