Wondering if I could cut a corner and use the PS that powers the Aleph J? Temporarily of course.
For an Aleph 30 build - if it's making +/- 24V rails you can use it all day, every day. If it's working for your AJ, it will work beautifully for the A30.
Assuming you're using a standard CRC supply now, the big differences from your current PS to the new one will be the final cap stages are separated per channel and the amount of capacitance you choose to use. Of course, you could tweak the resistors, too.
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Here we go. I’m going to replace my prototype boards with new boards to play with the new features. I’m starting to stuff the new boards with 221R’s.
This will be an Aleph 30, and I’m going to stuff mosfets in Q6, 8, 9 and Q10, 12, 13. Since I’m skipping Q7 and Q11, I’m also skipping associates gate resistors (R29 / 33) and source resistors (R37/41)
This will be an Aleph 30, and I’m going to stuff mosfets in Q6, 8, 9 and Q10, 12, 13. Since I’m skipping Q7 and Q11, I’m also skipping associates gate resistors (R29 / 33) and source resistors (R37/41)
Attachments
While I'm waiting my boards to show up I've made a BOM project on Mouser site so I thought to share it
This is for a stereo Aleph 30 and do not include Q1,3 - Q6,13. The parts are basically the same as build guide with some change doing to item unavailability.
https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=31d8553844
This is for a stereo Aleph 30 and do not include Q1,3 - Q6,13. The parts are basically the same as build guide with some change doing to item unavailability.
https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=31d8553844
Super cool! I thought about doing this over the weekend, but you knocked it out! Thank you!!
There's 5 or so possibilities for terminal blades. Is there a preference? https://www.mouser.com/c/?type=Circuit Board Blade Terminal
this is the one from the building guide BOM
https://www.mouser.it/ProductDetail/Keystone-Electronics/1287-ST?qs=lQmX4aIt5iBQmFQ9gmrtHw==
Thanks for that. What else am I forgetting that's not on the above BOM?
I'm going to order heatsinks and hookup wire. The stuff I have is not fat enough. Thinking of solid copper 20 gauge.
BTW, the boards look fantastic.
I'm going to order heatsinks and hookup wire. The stuff I have is not fat enough. Thinking of solid copper 20 gauge.
BTW, the boards look fantastic.
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Some minor suggestions.
ERX-3FJR47 - F letter means this resistor have Fe (Ferrum) leads. You may want ERX-3SJR47 that have Cu (Cuprum) leads. But they are not in stock.. Mouser said it is expected to restock 5/18/2022. And I guess it would be the last for those resistors.
CD15CD100JO3 - Kind of same for this mica cap. CD15 type have copper-clad steel leads. You may want CDA15CD100JO3 of CDA15 type that have copper leads.
@RainfallSky Thank you very much for point it out. As I specified I made some small change because some items are no stocked.
If one is concerned by leads material of 3w resistor (I'm not, but I'm not an expert at all) it easy to change with a different and stocked product..
the Dale CFP3 is a good alternative as I know
https://www.mouser.it/ProductDetail...=sGAEpiMZZMv0NwlthflBi0TzNR/RJBTvA2VczykiALs=
while the 10pF mica CD15 series cap is exactly the one I found in the building guide BOM
(I checked the CDA type but it is not available)
If one is concerned by leads material of 3w resistor (I'm not, but I'm not an expert at all) it easy to change with a different and stocked product..
the Dale CFP3 is a good alternative as I know
https://www.mouser.it/ProductDetail...=sGAEpiMZZMv0NwlthflBi0TzNR/RJBTvA2VczykiALs=
while the 10pF mica CD15 series cap is exactly the one I found in the building guide BOM
(I checked the CDA type but it is not available)
ZTX450
The little NPN transistors that form the Aleph CCS voltage reference and... something else down by the output MOSFETs appear to be backordered just about everywhere. Before I hit up my friends for these (haha), Mouser suggested this part as an alternative: the onsemi 2N4401-ND. The Vbe (that's the thing we care about here, right?) for this part is listed as a range of 0.75V to 0.95V at 150mA collector current and a maximum of 1.2V at 500mA collector current. The Vbe of the ZTX450 is listed as 1.1V at 150mA. Is the 2N4401-ND really a direct replacement for our application?
The little NPN transistors that form the Aleph CCS voltage reference and... something else down by the output MOSFETs appear to be backordered just about everywhere. Before I hit up my friends for these (haha), Mouser suggested this part as an alternative: the onsemi 2N4401-ND. The Vbe (that's the thing we care about here, right?) for this part is listed as a range of 0.75V to 0.95V at 150mA collector current and a maximum of 1.2V at 500mA collector current. The Vbe of the ZTX450 is listed as 1.1V at 150mA. Is the 2N4401-ND really a direct replacement for our application?
ranshdow,
I think there are several NPN subsitutes for the ztx 450's in these parts of the circuit. For example, in my Aleph J, I used the NPN BC550's without any issues. Unfortunately, out of stock as well.
Best,
Anand.
I think there are several NPN subsitutes for the ztx 450's in these parts of the circuit. For example, in my Aleph J, I used the NPN BC550's without any issues. Unfortunately, out of stock as well.
Best,
Anand.
The 2N4401 is a suitable replacement for the ZTX450 in both locations on the Aleph J.
https://www.mouser.com/ProductDetail/onsemi-Fairchild/2N4401TF?qs=TWXTHIu%2B82mgiBASxyU7hQ==
https://www.mouser.com/ProductDetail/onsemi-Fairchild/2N4401TF?qs=TWXTHIu%2B82mgiBASxyU7hQ==