@@Electronics4GuitarI think your presentation is really good. Heavy on the maths, which I struggle with sadly. I kinda felt like I walked into a room and was like woah, this is all way above me. What even is beta 🤷♂️ yeah it’s that bad. I love fixing stuff but have avoided the maths. I’ll go back to the start of your videos and work on my maths a bit I guess 😬. Great content though, thank you !
@@Mark_C1hi, Mark. Thanks for the feedback. Yeah, I definitely approach this stuff from a very technical perspective. What I envision is to eventually cover the whole field from basic RC circuits through transistors, op amps, vacuum tube amps and effects circuit operation and design. I also do plan to add a few videos that are more descriptive at some point as well. I taught EE for nearly 40 years so it’s hard to get out of that mindset. I definitely will keep the use of calculus to a bare minimum though 👍🏻 As far as transistors go, you might start with Video 12 and see if it helps with some basic concepts. I probably should have done an introduction to transistors first but I couldn’t help but jump right into it. Again, thanks for the feedback. And hopefully some of the presentations will be informative and thought provoking.
Sounds a lot like my experiences with Darlingtons back in the day as well. I always seemed to have better luck with Sziklais for whatever reason. Back in the 70s I would twist my dad’s arm to take me to a hamfest once a year and I’d try to find a good deal on power transistors, heat sinks, filter caps, etc.
I think the bdx33/34 were low saturation voltage designed for switching only nothing linear, didn't know what that was at the time, I just used whatever I could get, most of what I made back then didn't work well!
i when i was a kid with no money (early 90,s)i tried to use bdx33b and bdx34b as audio output , the bdx33/34 were plentiful from scrap barcrest fruit machine boards i was getting free, they use them to drive the lamp matrix ,they sounded really clear and livelly and werent oscillating but i could never control their thermal runaway. went to hitachi mosfets taken from dead disco / pa amps after that
I’m going in order of topics. I haven’t covered any op amp material nor any explicit theory on negative feedback prior to this so for the sake of good pedagogy I am holding off on that stuff until later. I’ll get to it eventually.
AS USUAL EXCELLENT PRESENTATION! WHAT ARE THOSE FOUR DIODES USED FOR IN THE COMPLIMENTRY PAIRS?IF I WERE BUILDING THIS CIRCIUT,I WOULD USE A DARLINGTON PAIR PACKAGE INSTEAD OF TRYING TO MATCH TRANSISTORS.
@@davidluther3955 the four diodes just compensate for the barrier potential of the output transistors. It’s not really possible to match them to Darlingtons because of the current differences between transistors. A Vbe multiplier could be used here too but the best way to bias this up requires negative feedback techniques which we haven’t gotten to yet.
Great presentation 👍
Just discovered your channel. Great content.
Now I have to go through the back catalog 😊
Glad you found the channel. I’m just getting started and hoping to generate a lot more content and hope to keep improving the presentation 👍🏻
@@Electronics4GuitarI think your presentation is really good. Heavy on the maths, which I struggle with sadly. I kinda felt like I walked into a room and was like woah, this is all way above me. What even is beta 🤷♂️ yeah it’s that bad. I love fixing stuff but have avoided the maths. I’ll go back to the start of your videos and work on my maths a bit I guess 😬. Great content though, thank you !
@@Mark_C1hi, Mark. Thanks for the feedback. Yeah, I definitely approach this stuff from a very technical perspective. What I envision is to eventually cover the whole field from basic RC circuits through transistors, op amps, vacuum tube amps and effects circuit operation and design. I also do plan to add a few videos that are more descriptive at some point as well.
I taught EE for nearly 40 years so it’s hard to get out of that mindset. I definitely will keep the use of calculus to a bare minimum though 👍🏻
As far as transistors go, you might start with Video 12 and see if it helps with some basic concepts. I probably should have done an introduction to transistors first but I couldn’t help but jump right into it.
Again, thanks for the feedback. And hopefully some of the presentations will be informative and thought provoking.
Sounds a lot like my experiences with Darlingtons back in the day as well. I always seemed to have better luck with Sziklais for whatever reason. Back in the 70s I would twist my dad’s arm to take me to a hamfest once a year and I’d try to find a good deal on power transistors, heat sinks, filter caps, etc.
I think the bdx33/34 were low saturation voltage designed for switching only nothing linear, didn't know what that was at the time, I just used whatever I could get, most of what I made back then didn't work well!
i when i was a kid with no money (early 90,s)i tried to use bdx33b and bdx34b as audio output , the bdx33/34 were plentiful from scrap barcrest fruit machine boards i was getting free, they use them to drive the lamp matrix ,they sounded really clear and livelly and werent oscillating but i could never control their thermal runaway. went to hitachi mosfets taken from dead disco / pa amps after that
Why no put some of the power output as negative feedback to U1B
...yes I know with some op-amps the phase reversal will happen in audio frequency, likely with LM358 maybe.
So choice of op-amp becomes a factor.
I’m going in order of topics. I haven’t covered any op amp material nor any explicit theory on negative feedback prior to this so for the sake of good pedagogy I am holding off on that stuff until later. I’ll get to it eventually.
Thanks 👍
AS USUAL EXCELLENT PRESENTATION! WHAT ARE THOSE FOUR DIODES USED FOR IN THE COMPLIMENTRY PAIRS?IF I WERE BUILDING THIS CIRCIUT,I WOULD USE A DARLINGTON PAIR PACKAGE INSTEAD OF TRYING TO MATCH TRANSISTORS.
@@davidluther3955 the four diodes just compensate for the barrier potential of the output transistors. It’s not really possible to match them to Darlingtons because of the current differences between transistors. A Vbe multiplier could be used here too but the best way to bias this up requires negative feedback techniques which we haven’t gotten to yet.
Sziklai Pair all the way!
@@Dazzwidd Sziklai rules!!
I blew up my headphones with only a few hundred millivolts in! I knew it was overkill to use a +/- 50V supply 😂
@@Dazzwiddbeen there, done that too lol 👍🏻