This amplifier will be used for other than driving 600 ohm input Z's. Driving headphone z is a current application for such circuits. About 1/2 of the headphones are below 600 Ohm Z.
30 ohms is not uncommon. For example, two of my headphones (Senn HD800 and HiFiMan HE6) are 300 and 50 Ohms.
Ic are limited in power handling but this is a discrete design and no such limitation need exist. Thx - RNM
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I hope we see a design come of this thread that is new or at least has some novelty, tweak or improvement over circuits most of us have seen shown here to death. That includes circuits that some experts believe is new but are available all over the internet and as old as 30 or more years. Possible ???
True but one designer may optimize for a different reason which may not be obvious to you but important factor to him, so how can one judge that his way is not optimal afterall it is trade offs. For instance J Curl will optimize for wide bandwith but this is not neccesarily good for THD while Edmond will go out of his way to post lowest possible THD. Which one is suboptimal ??
I think the percentage is much smaller than that, probably less than 10 percent when it comes to commercially available equipment.
I think the percentage is much smaller than that, probably less than 10 percent when it comes to commercially available equipment.
Patience please, geniuses at work on it. 
And then comes the dissapointment of seeing something weve seen years ago.....
And then comes the dissapointment of seeing something weve seen years ago.....
It doesn't have to be unique. It just has to meet specs.
current sources are not counted. But, even so, if you like it and it has more than 8, then since you're a genius you can fix it, right?
I saw some CFB types, but they had way more than 8 transistors. Do you have any examples you'd like to share or are you just going to talk talk talk???
I thought you already did that? You're asking US to design something for you?
That would be like Luke Skywalker teaching Yoda how to use The Force.
Hitachi FET To-220ab 200v .5A 30W GSD *SS | HITACHI *SS | Distributed By MCM
Hitachi Hitachi FET To-220ab N-ch 15V .5A 30W GDS *SS | 2SK215 | Hitachi
Hitachi FET To-220ab P-channel 180v 5MA 30W GSD *SS | HITACHI *SS | Distributed By MCM
Hitachi FET To-220ab P-channel 160v 5MA 30W GSD *SS | HITACHI *SS | Distributed By MCM
Number two (from post 68) is not too bad. Whose is it? It looks like something that really works.
Eight transistors is RM's idea, although he's already relaxed things a bit by suggesting he might accept cascodes as counting as a single device, and might likewise allow current sources.
I was thinking yesterday of days of yore when transistors were dear, and PNP silicon ones were just becoming available. Some active filter papers were showing a three transistor opamp (they called it a VCVS, voltage-controlled voltage-source, as it was used for that function and typically at very low closed-loop gains). They were quite pleased at the performance attained
Sort of the early Western Electric tube stuff in solid-state, and I don't doubt there are a few out there who believe that the simplicity somehow confers some sort of sonic excellence.