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

Some progress yesterday. I configured the DIYaudio soft start, 2x Antek transformers (stacked on top of each other), and 2x DIYaudio PSU (also stacked on top of each other) with the success for end result of +/- 71.5VDC! I haven't figured out why the -71.5VDC side of each PSU won't light the LED, maybe I installed it backwards? I can't wait for the new boards to be delivered!
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Check your led polarity on the side which didn't light up, that would be my guess.
Make sure the power lead is disconnected and the caps are completely discharged first.

Take your time to get the psu 100% and stay safe !
 
I am going to have to mull this over. Question: is there any point in shielded toroids if I have an entirely external PSU section?
You'd think the external chassis would provide the shielding, but not completely in my experience, I've had vintage pre/power combos that would hum like crazy through the speakers if the preamplifier is on top of the power amp. Lift the preamp amp and the hum would get audibly quieter the further it got from the power amp. Mind you, that was a poor 1200VA E-I transformer in the power amp that had a hard 40 years with no soft start and had some mechanical hum anyway.

I think it's primarily down to the winding+core quality, followed by potting. I've got a relatively cheaper Toroidy Audio grade coming for my EF3-5 so will be interesting to compare with the Supreme Audio grade I have here already.
 
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You'd think the external chassis would provide the shielding, but not completely in my experience, I've had vintage pre/power combos that would hum like crazy through the speakers if the preamplifier is on top of the power amp. Lift the preamp amp and the hum would get audibly quieter the further it got from the power amp. Mind you, that was a poor 1200VA E-I transformer in the power amp that had a hard 40 years with no soft start and had some mechanical hum anyway.

I think it's primarily down to the winding+core quality, followed by potting. I've got a relatively cheaper Toroidy Audio grade coming for my EF3-5 so will be interesting to compare with the Supreme Audio grade I have here already.
Shielded it is then. If they have their own shielding, I suppose I could just put them in a high temp plastic enclosure. Maybe even laser cut acrylic (I have a new giant laser machine I am just itching to use for personal project stuff)....... See through enclosure with chrome toroids and nice, fat, blue caps sounds fun..... now I might just do separate PSU just for the aesthetics lol.
 
Shielded it is then. If they have their own shielding, I suppose I could just put them in a high temp plastic enclosure. Maybe even laser cut acrylic (I have a new giant laser machine I am just itching to use for personal project stuff)....... See through enclosure with chrome toroids and nice, fat, blue caps sounds fun..... now I might just do separate PSU just for the aesthetics lol.
Non-ferrous metals perform poor for shielding low frequencies, iron cabinets are better choice then aluminum for this purpose.
 
I doubt you will draw more then 660 Watt continuous (6 A) while playing music in an domestic setting, I would not drop the Hypex soft start for that reason. However I have no data specific to their circuit, or your use of the amp, so this is a general assumption. Dedicated soft start for each transformer might bring up complications, like dual power switches, troubles with protection circuits and/or remote switching by preamp. In the end you decide.