Quick first observations:
Note the lower driver/output transistors are upside down...
Two diode drops isn't enough to bias such an emitter-follower output stage - a Vbe multiplier is traditional and allows for thermal compensation of bias as well as trimming to the exact bias needed, but 4 diodes would be better than 2 if sticking with this scheme.
Also a speed-up resistor/capacitor between the drivers' emitters would reduce switching distortion at high frequencies.
R6 as a pullup for the VAS will be a limiting factor for output swing - either bootstrapping or constant current source will improve this.
Note the lower driver/output transistors are upside down...
Two diode drops isn't enough to bias such an emitter-follower output stage - a Vbe multiplier is traditional and allows for thermal compensation of bias as well as trimming to the exact bias needed, but 4 diodes would be better than 2 if sticking with this scheme.
Also a speed-up resistor/capacitor between the drivers' emitters would reduce switching distortion at high frequencies.
R6 as a pullup for the VAS will be a limiting factor for output swing - either bootstrapping or constant current source will improve this.
What do you mean by newbie? New to the hobby entirely or new to amp design? If it’s the former, I’d suggest building a few proven designs first.
As far a reading goes, Rod Elliot’s site is a good start, and it’s free.
For books, I’d recommend Bob Cordell’s book as a start followed by Douglas Selfs book.
There are also numerous articles on the First Watt site and (of course) this forum.
Regarding your design, a general question of “is this any good”, is hard to answer. It’s open ended and subjective. It would help to state your design goals.
As far a reading goes, Rod Elliot’s site is a good start, and it’s free.
For books, I’d recommend Bob Cordell’s book as a start followed by Douglas Selfs book.
There are also numerous articles on the First Watt site and (of course) this forum.
Regarding your design, a general question of “is this any good”, is hard to answer. It’s open ended and subjective. It would help to state your design goals.
Hi Nishab, I have started a Youtube channel with educational videos which may be helpful to you. Check them out at:
SW Audio
YouTube
Regarding books, I would definitely start with Bob Cordell's book. After that, actually I would read Randy Sloan's book. And after that, maybe Douglas Self's book.
Best, Sandro
SW Audio
YouTube
Regarding books, I would definitely start with Bob Cordell's book. After that, actually I would read Randy Sloan's book. And after that, maybe Douglas Self's book.
Best, Sandro
Quasi-compliant output stage (three diodes or two diodes and a 100 ohm trimmer for setting current).
Q5 pnp emitter at the top.
Need 100 ohm resistors between base and emitter Q6,Q7 (SOA).
Fig 5.5b Проектирование усилителей мощности звуковой частоты - Дуглас Селф - Google Книги
Q5 pnp emitter at the top.
Need 100 ohm resistors between base and emitter Q6,Q7 (SOA).
Fig 5.5b Проектирование усилителей мощности звуковой частоты - Дуглас Селф - Google Книги
Ups!(
Compliant output stage (three diodes and a 100 ohm trimmer for setting current).
Q5,Q7 pnp emitter at the top.
Compliant output stage (three diodes and a 100 ohm trimmer for setting current).
Q5,Q7 pnp emitter at the top.
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