Tips for a New MKIII Hx build

I'm about to build a DX blame MKIII Hx amp and wanted to know if there were any tips or changes I should know about as a lot of you guys have already built one.

I'm buying some left over boards from a group buy that meanmann1964 had put together and plan to use two matching transformers that I pulled out some old Technics SU-G90 receivers. The transformers put out 50 volts so I will have 70 volts after rectification which is a little high so I will make sure all of my caps are rated for 100volts or more. I'm not sure about the Va rating of the transformers, but they are quite large and came out of a 135 watt x2 channel amp so using a pair of them should have enough current for this project.

One question I had was if I should change the 2n5551 and 2n5401 transistors to BC 556 and BC 546 ones and if I could up grade the MJE 15031 and MJE 15033 to a MJE 15032 and MJE 15034?

Thanks in advance for all the help!

Dale P.
Here is a picture of one of the transformers I'm going to use.


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Well my second transformer came smashed in the mail, so I'm thinking of pulling out the wallet and buying a new one from Antek. Is 800va enough for both channels? I would like to use one transformer to save some cash and also keep the enclosure as small as I can, unless you guys give me a really good reason to buy a transformer for each channel.

So do any of you guys have tips for building the MKIII, or should I just follow the posted values on the circuit board?

Dale P.


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