2stageEF high performance class AB power amp / 200W8R / 400W4R

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SA2015 4 channel VMOS

... small progress ...

Some vote statistics:

  • votes: 17, average: 4.59 of "5,1,5,5,5,5,5,5,5,4,5,5,5,5,4,5,4"
If we remove the invalid "1" from all votes

  • votes: 16, average: 4.81 of "5,5,5,5,5,5,5,5,4,5,5,5,5,4,5,4"
Have fun, Toni
 

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SA2015 4 channel VMOS - case parts

... today got missing parts to finish the amplifier case ...


  • Aluminium heatsink and top panel CNC machining and anodizing:
    high quality from schaeffer-ag.de!

  • Powder coating of inner iron shield::
    high quality from wolfmair.at!
BR, Toni
 

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Thx!

Case mount test so far OK. All parts fit.
Unfortunately the heatsinks are not 100% flat. During mounting the error is about 0.5mm in the middle. So we need some force to correct this during mounting.
Next time I need to do a better finish for the heatsinks before anodizing - especially for the saw edges.

Have fun, Toni
 

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Thx ... prices ... hmmm ... astronomic ...

but below EUR 1k including anodized feets, cnc machined and anodized heatsinks, inner iron shields, powder coating. Would be a lot cheaper if the top plate wouldn't be cnc machined aluminium but instead lasered iron and powder coated. The 4mm aluminium top plate is the most expensive part but it is worth the money - IMHO looks very professional.
A group buy would bring the costs down a bit but you still need some metal work skills and some special metal work tools.
BTW: for comparison - the toroid (8x35V AC / 850VA) is custom made and costs about ~ 300 EUR

BR, Toni
 

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Can I create an example using the +/- 100 volts?
And can add 2sc5200 as 10 12 pairs.
regards.

If you want to use 2SC5200/2SA1943 the driver stage needs to be redesigned. Driving those power bjt above +-70V isn't a good idea as AndrewT wrote!

If you want high power on 8R speakers you better do bridging using 2xSA2014 modules. you easy could get 880 W@8R. of course 4R speakers can not be used when bridged!

BR, Toni
 
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SA2015 4 channel VMOS

... testing the first amplifier module on the new heatsink ...

+/- 50V regulated power supply, VAS diode and SOA protection in situ, bias 250mA

THD+N 20k@105W@8R: 0.0026% (bw 80k)
THD+N 20k@200W@4R: 0.0068% (bw 80k)

SNR referred to full power:

  • 121 dB A-w
  • 117 dB bw 20k
  • 113 dB bw. 80k
  • 107 dB wb
noise:

  • 25 uV A-w
  • 39 uV bw. 20k
  • 62 uV bw. 80k
  • 137 uV wb
The IXYS mosfets have been mounted using blue keratherm U90 (alternative: keratherm 86/82). It is very important, that the thermal washer has low thermal resistance and you are using a proper sized heatsink. Otherwise you kill the mosfets when the amp should deliver continuous output of 200W@4R.

BR, Toni
 

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