Primitive single amplifiers

　　When I was making several headphone amps, I found that single amp has sweet and
natural tone. So I tried to design single power amp.




No. １　Bipolar amp


　Very simple circuit. As the value of Re is large as 39 Ω, it can go without thermal
compensation. However some transistor is going to heat up to crash.



No.2　ＭＯＳ−ＦＥＴsingle amp

　　I tried Toshiba K405. Tone character was rather gentle. Bias part can be more
simple at first stage.


No.3　Ｖ−ＦＥＴsingle amp

　　This amp was successful.　It was of good use with subwoofer.


No.4　DC amp

　　I made this, because I happened to find metalclad resistor. This goes to high
temperature.The sound was dull compared to that of Kaneta amp.

　　After those days I made drain output amplifiers, so all these amplifiers became
dead stocks.

　
Index