The Aleph-X

6. See the internet, and your library, perhaps a banker, structural engineer, electrician, HVAC contractor, metalsmith, various parts suppliers :clown:

Nearly lost my drink on this one, Bob! 😀

24V rails is plenty, but like Bob, I would recommend looking at a transformer in the range of 800-1000VA. For reading on the Aleph-X that is more condensed than this thread (though still somewhat lengthy- but at least it has headings) see my web page linked in my signature. A copy of AXE1-2 spreadsheet is there.

Eric
 
1. Yes, 24V is enough to reach 100W
2. See Aleph J-X - diyAudio 600VA or better highly recommended.
3. Search for AXE1-2 developed for the AX but works for AJX
4. See AXE1-2
5. Peter included part values with the boards. Use small form factor resistors for 1/4W parts
6. See the internet, and your library, perhaps a banker, structural engineer, electrician, HVAC contractor, metalsmith, various parts suppliers :clown:

Thank you
 
Nearly lost my drink on this one, Bob! 😀

24V rails is plenty, but like Bob, I would recommend looking at a transformer in the range of 800-1000VA. For reading on the Aleph-X that is more condensed than this thread (though still somewhat lengthy- but at least it has headings) see my web page linked in my signature. A copy of AXE1-2 spreadsheet is there.

Eric

Wow Eric, thank you very much, very very helpfull🙂

Felipe
 
My AXJ100 works with 24V rails 8A total bias per channel.
That is 400W power consumption.
I consider a factor of 2.5 minimum, which means 1000VA.
See also article by NP.

I actually use 1200VA core.


Patrick

Thanks Patrick, that's for stereo amp right? so for mono amp 200W power consumption so two tx 500-600VA.

Could you send me by pm or e-mail photos & your schematic with BOM please.

Thanks again

Felipe
 
I have to spend a fortune in heatsinks? could anyone link me to a proper heatsinks model to have an idea?

From my web page: I have 6 of these per mono. Total cost was about $200 per mono chassis. Others have used the heat sink guy who posts here on DIYAudio, though I am unaware of pricing. Seifert (spelling?) in Germany makes very high quality sinks, but they tend to be somewhat more expensive.
 
My Borbely 75w have each mono amp 4 heatsinks 30cm x 22.5cm (fins 4cm)
 

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My apologies, Felipe. My sinks are 10" (~ 25.5 cm) tall. Given your location, I would look into sourcing some Seifert (or other more local) heatsinks. They have one that comes in 18" widths (45cm). I'm just thinking that shipping from the US will be very expensive.

The "law of diminishing returns" applies to the length of your heat sinks. A 10" long heat sink does not provide twice the cooling capability of one that is 5" long, so making them much longer does not help as much as you think.

Eric
 
No, the link you have provided are TINY heat sinks intended for CPU cooling and are not appropriate for an amplifier. The rating of those is 0.8 c/w WITH A FAN.

The sinks I used are 0.8c/w per 3" (80mm) length. Since mine are 10" long, they have a c/w rating of somewhere near 0.43 c/w with natural convection (no forced air with a fan). Using 6 of these per mono provides about 0.07c/w for the entire chassis.

The final size of my chassis is determined by the size of the heat sinks. One mono chassis measures 20" deep (3 sinks side by side), 12" tall (10" sinks + 2" legs) and 14.5" wide (10" of interior chassis space plus 2.2" of heat sink on each side) and weighs over 65 lbs.