Followers and Quickie
- Thread starter Jamier
- Start date
D
Deke609
Guest
Jamier said:
Yup. I got the non-"PWM" version. I'm not tech-savvy, but I think PWM involves powering stuff from the motherboard. My fans came with a 3-wire/3-pin socket. I cut off the socket. Somewhat frustratingly, the wires are not color coded, so I had to experiment by process of elimination to figure out which was DC+ and which was DC-. It will only work one way. Reversing + and - makes the fan whir and sputter. I think the third wire is for a sensor or something - connecting it to power does nothing. But you could just as well google the 3pin socket to figure out which is which. But then you'll have to take the socket apart to keep track of which identical looking black wire is attached to which pin. Worst case scenario: it will tkae you 10 min to figure out which is which.
And note the fans are pretty big - 140mm. They also come in a 120mm version. And you could always get smaller fans from another manufacturer. I hit on the "Silent Wings" after a quick google search for "quietest computer fan" - there are other really quiet fans out there. But I didn;t feel like fussing for hours just to get 1 or 2 less dB.
cheers, Derek
Derek, How will you power the fans? Battery, or some simple PS? 140mm is probably about right. the heatsink measures around 5 1/2 or 6 inches square, more or less. Actually it's about that tall too, so think of a 6 inch cube shape with fins, sharp, hot fins. I think the fan will be a good upgrade as long as it's not too noisy!
Jamie
Jamie
D
Deke609
Guest
I haven't decided yet. I am going to mock up the BeePre rebuild using plywood to play around with layout to eliminate/minimize noise. I'll test various options then. Battery is obviously the safest bet noise-wise, since the power supply wouldn't be connected to either the amp wiring or mains. But some folks on DiyAudio who've used fans report no injection of noise running the fans off the amp filament supply. B/c I'm installing separate filament supply transformers, the existing 6.3V secondaries can be repurposed - so I'll try running the fans off of those (after doubling/rectifying and smoothing) and compare with battery power. If I can't hear or measure any additional noise, I'll go with using the 6.3V windings. But if that proves noisy, I'll try a separate trafo (10 or 12V). I might even try (being the crazy guy that I am) using a C4S in from of them to isolate them - but this assumes that isolation of the C4S (which I assume is function of impedance to AC - but don;t know) works both ways: PS and load each isolated from each other. Not sure if it does work that way or is instead one-directional.
I think I may also install a pot to control dc voltage/fan speed. To be even fancier, one can install a temp sensor or thermistor that controls fan speed. I'm thinking about that, but will probably leave it as something fun to play with in the future.
cheers, Derek
I think I may also install a pot to control dc voltage/fan speed. To be even fancier, one can install a temp sensor or thermistor that controls fan speed. I'm thinking about that, but will probably leave it as something fun to play with in the future.
cheers, Derek
The Mainline won't take much more than 1.1V, but it has loads more gain than a Crack does (especially with the impedance switch set to High).
I would set the output of the DAC all the way up and just use the attenuator on the Mainline as your primary volume control.Jamier said:
I would blow the air onto the heatsink.
PB, do you know the V output of an rDAC? It seems to be a better match with the Crack. I installed an Noctua Redux 900 fan in one of the MoFos. The fan cooled side is running 12-15 degrees C cooler than the other so I’m going to put the same fan in the other amp and the install the 193 Vs.
Jamie
Jamie
