Chinese Pass amp clone

Drilling and tapping by hand is pretty labor intensive. That is what makes the heatsinks at the store a good deal. If you purchase the predrilled heatsinks, you can attach the output mosfets with little wire leads as I showed in a previous post as the holes won't match your amplifier boards. but you can probably macgyver that.

Also, the 4U 300mm heatsinks may not be enough if you build a wood chassis as the metal top, front and back move heat too. Wood isn't thermally conductive compared to aluminum.

Here is a wood chassis Aleph mini. Heatsinks got pretty hot but it worked for it being pretty low wattage.
What speakers are you powering with the Aleph? If you need the 30 to 40 watts and want to use the DIY audio store heatsinks, you are probably going to want to step up in size. Which again narrows the money gap I mentioned before 😬
I believe I have seen the heatsinks for the Aliexpress chassis I linked available. They would likey be good to work with as they are pretty large and one piece.

That particular chassis could probably handle being built into Aleph 2 monoblocks. Puts of a good amount of heat
 

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Here are the heatsinks by themselves from that chassis. I mounted the bridge rectifiers onto the wood of that amp in my previous post. Not the best idea with an aleph 30 as they need to dissipate heat. On the little amp, they stayed at around 50c because not too much current.

heatsink

The heatsinks are the most expensive part of the chassis which makes it difficult to save much money.

Here is another site that you can look at:

https://www.heatsinkusa.com/?gad=1&...AnnL8zj0jUx_p8ta3aoVkg9yVmOQDxshoCNfEQAvD_BwE

you can also find heatsinks on Ebay. Make sure they are bigger than the 4U 300mm heatsinks. DIY audio's wavy heatsinks are pretty efficient for their size.

Steel at home depot is fairly inexpensive for the bottom and back. Wood front looks cool. In the metal section at HD or Lowes, there is a metal mesh that is stamped out of metal sheet that looks good when hit with black spray paint. then there are angle brackets, screws and unexpected bits and pieces when building your own amp from scratch.
 
For some reason, there is not always a quote button available. I will buy the drilled heatsinks as I am likely to screw it up.

I wasn't going to enclose the amp in wood. It's just for the bottom plate.

I have several sets of speakers that I can use in my studio apartment. But the main set (83db Acoustat hybrids) may be iffy.
 
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83 db, yeah, you probably need the 30 watts. Keep an eye on the temperature of the bridge rectifiers if mounting to the wood. Touch them with your finger. If you can keep your finger on them for a few seconds before the heat bothers you then you should be good. Maybe elevate them with a couple washers between the wood and the bridge rectifier.

I see you are being sent snubber boards for the rectifiers. They aren't needed but bennificial. There is a Quasimodo snubber results page. Being that youare inthe US, a antek AS-3218 is a good transformer to use. I am pretty confident that the snubber resistor value is posted in that thread. If you search that thread (at the top) for "3218" you will probably find a few results. Typically between 7ohms and 15ohms.

Those purple snubber boards are from randy's Aleph UMS thread. Info should be in the Aleph 30 build guide.