Honestly, I have no idea how well changing out the A56 and A06 with other devices will work. Quite possibly it will make little difference. On the other hand, it could introduce instability. I know my technical advisor would ask “what do you hope to gain” in making a change to a proven, tested design. At a minimum you must verify that stability and distortion have not degraded. She would say her time is better spent taking a nap…
A good topology is pretty forgiving of minor variations in device characteristics. So substitutions of parts generally have only minor effects.
A long time ago, I decided to simply ignore people asking me to spend time incorporating whatever device they were keen on, as I knew it would only make a very small difference for significant effort. It's easy saying "have you tried blah part", but without actually trying blah yourself you're not really making much of a contribution, and tasking others with trying it because you don't want to expend the effort yourself is simultaneously arrogant and lazy.
Much more interesting is changes to topology, as that's where big gains come from. By far the most interesting thing I've done with this amp is the folded cascode that I incorporated for the class G version. Unloading the first stage speeds it up significantly, and really improves the distortion performance without stability issues.
A long time ago, I decided to simply ignore people asking me to spend time incorporating whatever device they were keen on, as I knew it would only make a very small difference for significant effort. It's easy saying "have you tried blah part", but without actually trying blah yourself you're not really making much of a contribution, and tasking others with trying it because you don't want to expend the effort yourself is simultaneously arrogant and lazy.
Much more interesting is changes to topology, as that's where big gains come from. By far the most interesting thing I've done with this amp is the folded cascode that I incorporated for the class G version. Unloading the first stage speeds it up significantly, and really improves the distortion performance without stability issues.
I would like to thank you. We, as diyaudio producers, are following the path of good diy artists like you. I am currently listening to the 50w r2 version you designed and it really sounds good to my ears, so it deserves to be boxed. In general, the jfe2140 is the one I liked the most from the jfetlers I listened to, I also made a PCB to evaluate my sleeping nichicon capacitors and selected exicon mosfets in my drawer. I have been liking dc amplifiers since I started to deal with these things. I would like to thank cyberpup for the jfe2140 and servo version of your amplifier.
question:
at suzyi amp the R46 (zobel network) is a 3W wirewound implemented.
at cyberpup Myka SJ R46 is about 1W. ...e.g. MMB02070C1209FB200
just 1Watt?
i have the Myka SJ pcb and i plan rail voltage 34-40V
at suzyi amp the R46 (zobel network) is a 3W wirewound implemented.
at cyberpup Myka SJ R46 is about 1W. ...e.g. MMB02070C1209FB200
just 1Watt?
i have the Myka SJ pcb and i plan rail voltage 34-40V
If the amp is behaving the zobel dissipates stuff-all. If it's oscillating you'll burn your finger whatever resustor you use.