Hiraga Class A Build Question

Hello audio geeks

I won this incomplete build in an auction. I was going to complete it however wanted to first confirm before firing it up:

  • This build uses high current 24V SMPS, is an SMPS suitable for this build?
  • If the above is the case, I could consider a DIY Audio Store SMPS filter kit to block any conversion noise?
  • Otherwise, a conventional PS is better?
  • Is existing heatsinking likely to be OK, or inadequate? This is class A after all......

Keen for your thoughts. I can use the case for another build if this is likely to be a no-go.

Thanks all!
 

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I would finish it as-is and see if you like it. There would be a lot of work and cost to convert it to a linear power supply.
However, the heat sinks are being poorly used, since the transistors are mounted very close together.
 
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These power supply will mostly overheat since a real Meanwell LRS-350-24 has a cooling fan. On yours they have removed the cooling fan and also partially blocked the supply ventilation since the amplifier modules are located just above the power supplies. Awful design.
Do a search, there’s a huge Hiraga thread.
 
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Both rayma and e_fortier provide good advice. The Hiraga pcb looks decent enough, the drivers with their separated own cooling sinks (utmost important!).
Maybe the fans were removed because of the noise (the supplies are capable to throw 14A away according to the label), but I would search for four equal fitting fans, all for the rated mains voltage (NZ is 230, not?), having two of them in the smps's, and the other two outside the smps's but inside the case, blowing towards the mounted output transistors. And, to keep things silent: have two fans in series connected running on half the mains supply voltage. Fan smps left in series with fan heatsink left, same right side. Some work with wiring though.
Give it a try as is (#2), modify to suit your needs later.
 
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Thanks for the advice all. I had no idea about the missing PS fans. I have to say that I will most probs pass on this project. Im more interested in repurposing the case & hardware for a Holton Audio FET build thats quite high power. It sounds like (based on my research) that these Hiraga modules can be tricky and I obviously have the added issues here. thanks