Pictures of your diy Pass amplifier

Hi

Here’s some pictures of my F3.

I had the heatsinks already from a member here and my friends provided the ventilated top, bottom. I then worked on the back and front pieces. The front is 10mm aluminum that I worked on to get the brushed effect, I’m happy with the results. I have used 1 SMPS per channel (200W each), one on top of the other with the added SMPS filter from the diyaudio store on each channel. It’s quiet as a mouse and I’m loving the sound. AC current gain set to 50%.
Bias is 1.7A therefore each channel dissipate about 75W, heatsink are at about 45C after 2h and stable.

It was a long build considering the case wasn’t bought ready made but I really enjoy the whole process, fun factor to the roof.

Eric
 

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With 6s 2800 I’m running it for about 1 hour. Voltage drop with lipos is so linear that it’s not a problem and the bias isn’t changing. I’ve also got tons of 6s 3300s that I’m staring to use. So, two of those for an evening of listening.

Lipo powered this thing sounds really amazing. Easily as good as any of my Pass or tube amps.
I have a few 100aH AGM batteries since I converted my travel trailer ti Lithium.....I'm going to use them through a Bucking device to stabilize the voltage to 24V to power an ACA Mini.......Thanks for the idea!
 
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The One Day Wonder!...The Nelson Pass ACA Mini is done and playing through a set of Fluance speakers. Driven by a Schiit Freya with a WiiM PRO streamer and Topping DAC......Sounds pretty amazing. More listening is required. A real fun project....Started around 9AM...Finished at 9PM.....Amazing how much volume through the Fluance speakers. I want to be sure it doesn't do anything funny before I connect it to the KEF and Magnapans.....
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I really like the coolers. Are they fairly quiet? How does it sound?
Regards, HeyBill

Yes, I cannot hear them from my listening post and the speed can be adjusted to taste. Really the larger CPU heatsinks and esp. the high end ones are designed for low noise. These heatsinks came out of a computer that was liquid damaged so I salvaged them and finally repurposed them for Aleph J build.
 
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Yes, I cannot hear them from my listening post and the speed can be adjusted to taste. Really the larger CPU heatsinks and esp. the high end ones are designed for low noise. These heatsinks came out of a computer that was liquid damaged so I salvaged them and finally repurposed them for Aleph J build.
Very nice and original concept.
To avoid someone being zapped I would recommend adding a ventilated cover above your 2 switching power supply.
 
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