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

Another SA 2014 is going to be born ;)
 

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  • Output stage SA2014.jpg
    Output stage SA2014.jpg
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Dear Asuslover,

I was trying to make the smallest managable dimensions. My limitation due to my hifi shelf are 48cm wide and 40cm deep at max. Another limits are heatsinks. I decided for two pieces of K 190 heatsinks per channel. They are 190mm wide, so I concluded that the spreader is 381 mm long. (1mm is reserve, because I am not mechanicaly perfect). The heatsinks you could find/buy from the company Gamaaluminium. The catalogue is at the link Hlinikove chladiče | GAMAaluminium - the catalogue is in English, too.

I did not make holes manually. I ordered the all the alluminium parts from Customized front-panels, electronics panels, face panels, device panels, front-plates, anodized panels, aluminium panels
They are professional maker of front pannels for Hifi devices at reasonable prices. They provide simple CAD software where you can design your pannel and then they produce it. I can share the design of spreader if somebody would be interested. (The price for 2 pieces of spreaders 6mm thick is 53 Euro plus postage.)

Ladislav
 
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I think the heat is spreaded very well in this case. So I dont see any difficulties with two pieces.
:)

The K190 has 0,47 °C/W if 150mm high. Think you have about > 120mm heigth?
2 of them with heat spreader may get down to 0.25 -0.30 °C/W

Idle dissipation is about 60W per channel. This gives about 18 degree above ambient. May not need active cooling. OK - depends on your room temperature and use case.


For example my 4 channel SA2014:
A 210mm high ct-540 has ~ 0.15 °C/W. I have mounted 2 channel on one of this heatsinks. Total dissipation in this case is 120W per heatsink. gives nearly the same temperature above ambient like the double K190 with heat spreader!

Well done!
 
SA2014 modules wired. At this moment still without loudspeaker protection. Everything is working, idle current set to 21mV/0,47 ohm (44 mA per device) at cold heatsink.
Iddle current is decreasing with higher temperature. It drops to 15mV/0,47 ohm (32 mA) when stabil heatsink temperature is achieved.
Output offset is measured about 4-7 mV.

I am looking forward to listening experience.

Ladislav
 

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  • sa2014 wired.jpg
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SA2014 modules wired. At this moment still without loudspeaker protection. Everything is working, idle current set to 21mV/0,47 ohm (44 mA per device) at cold heatsink.
Iddle current is decreasing with higher temperature. It drops to 15mV/0,47 ohm (32 mA) when stabil heatsink temperature is achieved.
Output offset is measured about 4-7 mV.

I am looking forward to listening experience.

Ladislav

it seems your toroids will have a shorted turn via the center bolt , please check .
 
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Joined 2011
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Dear Toni,

I am not sure I understand what you mean by output negative pole. There is speaker connector and the GND. Both of them are connected. In the input there is 10 pins connector so I hope that it is not mismatched.

BR, Ladislav
The IPS and the OPS grounds are only connected via a 10R resistor to keep the input ground clean. The IPS input ground pin need to be connected to speaker output ground. This wire should be routed as far away from toroids as possible.