AB100 Class AB Power Amplifier

Still a lot of work, but getting there...;)
 

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I plan to try the AB100 at lower, +/-30V rail voltages and increase the output bias current as suggested before by multiple members, including NP. Do I really need the 4 output pairs, then? From a SoA point of view even 1 TIP142/147 pair would be safe at 4 Ohm load, whereas 2 pairs seem to be an overkill already. How many pairs would you use at +/-30V rails and why? If it is less than 4 pairs in the end, do I need to adjust something in the front-end?

Thank you,
Miklos
 
Thank you, osscar, for confirming. I would be also interested to learn if there are "audible" arguments for more/less output pairs when technically they are all fail safe. I read here and there that "more pairs are better because of lower output impedance and THD" while others say that "single pair is the best due to lacking degeneration issues" etc. Not being experienced enough myself, I am somewhat confused how to find my way across such apparently contradicting statements. What would be your educated guess?
 
That phrase that says quickly, only thing that happens quickly is trouble, so have to take time to get it right.;)
:)
 

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Will hopefully be completed this week. Bought a hole saw for 16mm hole and it cut a 17mm hole on the face plate for the ON/ OFF switch, the we make a plan...
 

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Is the bias with .5R resistors still 20mA per transistor? Pretty sure I had two outputs go up in smoke and then accidentally swapped the NPN and PNP outputs which led me on a wild goose chase. I did figure out you can check the front end by removing the outputs without doing anything special. I then tried just one NPN and one PNP and it worked perfect. I now have all the outputs installed and it is working perfect, just wondering on the bias.