NF-A12x25 PWM
Human ear begin to listen to about 19-21 dB. (A) -> measured at 1 meter.Rotational speed (+/- 10%) 2000 RPM
Rotational speed with L.N.A. (+/- 10%) 1700 RPM
Min. rotational speed (PWM, +/-20%) 450 RPM
Airflow 102,1 m³/h
Airflow with L.N.A. 84,5 m³/h
Acoustical noise 22,6 dB(A)
Acoustical noise with L.N.A. 18,8 dB(A)
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Is there a starting point setting on the adjustment pot? I realize there is no load yet.
Drpro,
Jan’s suggestion is spot on. But in case you forget to preadjust, there is only about 1V of adjustment to be had, so no fear of damaging anything.
Good luck with your build!
+/36v rails = 72v total x 3 Amps = 216W per channel
216W x 0.19C/W for the 250mm x 40mm x 210mm heatsink is 41C rise.
Assume ambient temps are 20C to 25C, possibly 35C in some parts of the world in the summer with no A/C. Taking even the coolest A/C settings of 20C, we get 20C + 41C = 61C. This is 6C higher than the recommended 55C max (based on burning one's hands from touching the sink). So unless you are prepared to back off on the bias current and/or rail voltage, I don't think the 5U is big enough.
However, even a very low speed (silent) Noctua 120mm fan blowing against the outside of the heatsinks would bring the temperatures down significantly. However, if you will use a fan, may as well go with heatpipe CPU coolers and save tons on the chassis/heatsink.
216W x 0.19C/W for the 250mm x 40mm x 210mm heatsink is 41C rise.
Assume ambient temps are 20C to 25C, possibly 35C in some parts of the world in the summer with no A/C. Taking even the coolest A/C settings of 20C, we get 20C + 41C = 61C. This is 6C higher than the recommended 55C max (based on burning one's hands from touching the sink). So unless you are prepared to back off on the bias current and/or rail voltage, I don't think the 5U is big enough.
However, even a very low speed (silent) Noctua 120mm fan blowing against the outside of the heatsinks would bring the temperatures down significantly. However, if you will use a fan, may as well go with heatpipe CPU coolers and save tons on the chassis/heatsink.
I could be wrong - but I think that rating is for the combined total heatsink, two are used to form the one with this rating. I don’t recall any Modushop 5U that could take 400W per side.
I could be wrong too, but I think it's per heatsink. The diyaudio store states this:
"The 5U Deluxe (400mm Deep) contains four heatsinks and each is rated at 0.28 C/W" (40mm Heatsink Information – diyAudio Store)
At modushop you can order a single heatsink and they say:
"Used for the 5U container 500mm deep, coefficient 0.19 C ° / W" (Dissipatore 250 X 40 H 210 mm)
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