I'm not going to bother asking this time... you're getting another Aleph-X build thread like it or not. 
The F5 is barely broken in and already working on what this might look like.
Current plan is to build monoblocks 100W/ch version. Thinking each of the enclosures would be about twice the heat sink of my F5 with four sets of mosfets each on a 11"x5"x2" sink. That seems about right given how much dissipation I expect out of the Aleph X vs. the F5 and the fact that my F5 heat sinks are relatively cool (can hold hands on them indefinitely.)
Not sure if I'm going to make a separate PSU enclosure or not. Either way, it will be dual mono CRC. Thinking two Antek 800VA 20V transformers. Trying to decide on caps. I was thinking six 47000uF 35V caps for each but after reading a bit, I think I might be able to get away with less capacitance and perhaps 25V caps. That could cut my cap cost by half or so. Any commentary on this?
Thinking these vs. these.
Also, does Q6 also need to be matched to Q5 and Q7? I didn't think so, but wanted to make sure. I was thinking about building my own matching rig, but I don't do this often so I'll probably just buy a couple pairs from ebay.
The F5 is barely broken in and already working on what this might look like.Current plan is to build monoblocks 100W/ch version. Thinking each of the enclosures would be about twice the heat sink of my F5 with four sets of mosfets each on a 11"x5"x2" sink. That seems about right given how much dissipation I expect out of the Aleph X vs. the F5 and the fact that my F5 heat sinks are relatively cool (can hold hands on them indefinitely.)
Not sure if I'm going to make a separate PSU enclosure or not. Either way, it will be dual mono CRC. Thinking two Antek 800VA 20V transformers. Trying to decide on caps. I was thinking six 47000uF 35V caps for each but after reading a bit, I think I might be able to get away with less capacitance and perhaps 25V caps. That could cut my cap cost by half or so. Any commentary on this?
Thinking these vs. these.
Also, does Q6 also need to be matched to Q5 and Q7? I didn't think so, but wanted to make sure. I was thinking about building my own matching rig, but I don't do this often so I'll probably just buy a couple pairs from ebay.
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20V transformer will give ~28V rails. you need the 35V caps. You could getaway with 4 X 47K uF per channel, but 6 is better.
On one of the aleph-X threads, there is a spreadsheet for working out the power supply requirements, power dissipated for different voltages and bias settings. I suggest you find it, it should help you work out what you need for sinking.
BTW there is a thread for the aleph-X, if you post your questions there, you will more likely get assistance from the people who are subscribed to that thread already
On one of the aleph-X threads, there is a spreadsheet for working out the power supply requirements, power dissipated for different voltages and bias settings. I suggest you find it, it should help you work out what you need for sinking.
BTW there is a thread for the aleph-X, if you post your questions there, you will more likely get assistance from the people who are subscribed to that thread already
Hello,
I am also planning on building an aleph jX.
You can use less capacitance, but make shure that the ripple does get to big.
Also dont forget about the ripplecurrent. The first C from your CRC filter has to handle big ripple currents.
I would go for the 35V version.
Has also 7.7A ripple current instead of the 5.5A of the 25V one.
You could use PSU designerII from duncanamps.com to check the ripple current.
When i did my simulation of an CRCRC filter for my AJX 100w. my ripple current was something like 30 or 40A. So i am going to probably use multiple C's in the first C of my CRCRC to cope with the ripple current and also lowers ESR. I am using 1kva 20V sec toroid, i am going for 35V caps.
Check out digikey. they are maybe cheaper.
I am also planning on building an aleph jX.
You can use less capacitance, but make shure that the ripple does get to big.
Also dont forget about the ripplecurrent. The first C from your CRC filter has to handle big ripple currents.
I would go for the 35V version.
Has also 7.7A ripple current instead of the 5.5A of the 25V one.
You could use PSU designerII from duncanamps.com to check the ripple current.
When i did my simulation of an CRCRC filter for my AJX 100w. my ripple current was something like 30 or 40A. So i am going to probably use multiple C's in the first C of my CRCRC to cope with the ripple current and also lowers ESR. I am using 1kva 20V sec toroid, i am going for 35V caps.
Check out digikey. they are maybe cheaper.
it does not matter if they are 0.33R or 100R. its the total R that matters.
and 0.1-0.2R is a nice value. i will say 25W is a minimum.
i am more worried about your heatsinking. this is a very big demand on this amp.
by total R i meen for all the resistors. so 5 pc 5W resistors is good.
then you can use 1ohm resistors. that gives you 0.2R total and 25W.
the higher R you use the more dynamic you loose. and that you don't want
regards to heatsinks. bulding high is not the best way to go.
if you dobble your hight you only gain 40% on C/W rating.
if you place them side by side you gain 100% on C/W rating.
you need C/W rating of 0.2C/W pr side or lower.
f.ex. if you have 2pc of 0.4C/W sinks on top of each other. you get around 0.32C/W. if they are placed sid by side, you get 0.2C/W.
they only come in raw alu. i don't know if they do anodizing.
you can also powdercoat them if you want
From the web page oneplustwo linked to in post #10 the following is just above key specifications:
"To specify the color of your heat sinks, attach the suffix-x:
-B black anodize -C clear anodize"
RC
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