DIY Class A/B Amp The "Wolverine" build thread

I'm just starting to look into building a Wolverine as a winter project. This is a long thread so forgive me if this has already been addressed, but when I look at all the effort being put into matching the input pairs, why not use a matched dual pair like Diodes Inc etc make? They typically use die that were adjacent on the wafer so it's hard to imagine you could match random die as well.
 
Do I not know how to use a power supply or is it these cheap Amazon power supplies? I am trying to do my testing and I'm on my 3rd bench power supply. I set the voltage to 60 I set the amps to .3 and I hooked it up to my boards and I only get .025 amps every time, no matter what I set the amperage or voltage to. It starts in CC mode then when i put the load of the amp on it, it changes to CV. Only getting 4 of the 6 leds to light up.

https://www.amazon.com/dp/B08FT18FQL?ref=ppx_yo2ov_dt_b_product_details&th=1
 
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Oh, I see now. You hook it up to one side to get the + OR the other for -.
Make sure you know how to hook them up. Chances are... it may not be the way you think. There really is no 'negative' supply. If you hook up only black and green and think you're going to get something usable, that is likely not the situation. That may not be what you're thinking or describing above... but just in case.
 
Make sure you know how to hook them up. Chances are... it may not be the way you think. There really is no 'negative' supply. If you hook up only black and green and think you're going to get something usable, that is likely not the situation. That may not be what you're thinking or describing above... but just in case.
Thanks for this, you might have saved me from damaging my boards. I've seen how to make a negative rail before, but wasn't thinking about it with these. More testing info, like how to set up the bench power, might be good to have in the guide or the dropbox. Finally get to do my testing now :)
 
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Thanks for this, you might have saved me from damaging my boards. I've seen how to make a negative rail before, but wasn't thinking about it with these. More testing info, like how to set up the bench power, might be good to have in the guide or the dropbox. Finally get to do my testing now :)
My pleasure... It's tough when lots of people are answering at the same time or close to the same time. I posted just as the person in front of me posted initially, and you've gotten a little more information in between.

It sounds like you have multiple supplies. Are they the same?

I'm on my 3rd bench power supply

Maybe they all still work, and you did not send them back?

You may be clear, but let's be sure. Do you (with a high level of certainty) know how to connect two supplies properly to accomplish what you need? There can be some safety issues. I have done it with my supplies, but I'm not confident enough to tell you to do it with your supplies.

What might be best is if you set up the supply that you're actually going to use for the amplifier and current limit and/or ramp up the voltage accordingly for testing.

Good luck, and have fun!

:2c:
 
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What might be best is if you set up the supply that you're actually going to use for the amplifier and current limit and/or ramp up the voltage accordingly for testing.
Agreed, you don't have to bump it up to full rail voltage and switch it on.
There's no harm in setting the bench power supplies to the recommended current limit from the build guide. Then set the voltage to ±1V and then turn it on and dial up the voltage from there. If you find that one or both of your power supplies hits the current limit and your not able to increase the voltage any further then this is a sign that you have a problem.
 
If I'm not mistaken, I believe that it does tell you to verify with your DMM that you have +Rail Voltage, 0v, -Rail voltage before connecting power to the boards.
Yeah, but I had no idea how to get that voltage in the first place. Didn't know i needed two bench power supplies or how to wire them to get negative voltage. How to hook them up. It might be a given for you guys and gals that have done this before, but for us first timers it's not so straightforward. Just want to help the next person out to make their build a little easier.
 
I figured out the negative voltage, and luckily I hadn't returned one of the power supplies yet. One of my boards measured great. The other everything is OK except for I'm only getting 4 lights and measuring from TP104 to speaker ground I'm getting - 32.36v which is less than than 0.080 stated, but is it OK to be that much less? What should I look for if that's not ok? I knocked c123 and c124 around a little when trying to install transistors, could that be it?