I am aware of all these changes one can make to the Brian boards but it does get complicated for someone just building their first amp. I made the changes talked about Aleph Design Reloaded but this was after building 5 or 6 other amps. When I built my first Firstwatt amp I wanted it to be as simple as possible, stuff my boards and get that sucker playing music without complications. There is a lot of information to be found on the Brian boards but to make the first build as smooth as possible I believe you will be better getting the store Aleph J boards and the jfets and make it as painless as possible. The Brian boards were great before the store boards came out because it was all we had. If you proceed with the Brian boards everyone here will be glad to help if you need it including myself.
You will not find the excellent build guide with the Brian boards that 6L6 did with the Aleph J.
http://www.diyaudio.com/forums/pass-labs/241729-aleph-j-illustrated-build-guide.html
You will not find the excellent build guide with the Brian boards that 6L6 did with the Aleph J.
http://www.diyaudio.com/forums/pass-labs/241729-aleph-j-illustrated-build-guide.html
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To build an Aleph 30 do I need a matched sextet/cannel of IRFP240?
In some site I read that the mosfets should be matched a pair...So do I need a matched sextet or 3xmatched pair?
I think that I buy mosfets already matched from an expert builder!
You can buy matched, but where is diy? There isn't such an easy stuff as matching mosfets 🙂 You just need some 20V source (Laptop power supply) and 56Ohm/5W resistor of any kind.
Those in the same branch need to be matched, so equal current goes through them, and they dissipate equal heat.
http://www.firstwatt.com/pdf/art_matching.pdf
Also, input differential pair must be matched (IRF9610).
If you choose Jfets for input (going to Aleph J) then buying matched Jfets would be good idea since their Idss can vary much, but I don't know who does that on the net.
If you decide on Babelfish tough, see this: http://www.diyaudio.com/forums/swap-meet/273336-babelfish-j-package.html
Everything matched and ton of support from ZenMod 😉
Those in the same branch need to be matched, so equal current goes through them, and they dissipate equal heat.
http://www.firstwatt.com/pdf/art_matching.pdf
Also, input differential pair must be matched (IRF9610).
If you choose Jfets for input (going to Aleph J) then buying matched Jfets would be good idea since their Idss can vary much, but I don't know who does that on the net.
If you decide on Babelfish tough, see this: http://www.diyaudio.com/forums/swap-meet/273336-babelfish-j-package.html
Everything matched and ton of support from ZenMod 😉
Yes, true whay you say. But reading about matching mosfets I read that it is necessary a very expensive precision multimeter...I have a cheap one.
Do you have cheaper then this one?
This is the I've done it, and... 🙂
An externally hosted image should be here but it was not working when we last tested it.
This is the I've done it, and... 🙂
Yes, similar at your.
But I don't understand, well I don't know, how transform the schematica test circuit in a real circuit...sorry...Do you have a picture of the circuit test and the pieces to build it?
Do I need a heatsink?
Now more clear?
No heatsink needed, for just a few mins of measuring. If you want to stabilize current and heat for half an hour, then attach it to a heatsink, not some big. But not some special need for that... Few mins of measuring is simply enough.
Sry, don't want to force you in matching if it is difficult for you, but I have had the same reaction for the first time. Matching mosfets? Whey!! That's something difficult!
When I did it for the first time with success, I said, huh man, this is like a piece of a cake...
And the point is in learning, though 😉
When I did it for the first time with success, I said, huh man, this is like a piece of a cake...
And the point is in learning, though 😉
When I find time to draw a simple sketch, I'll show you what I understood and I explaine you my doubts. Yes, I would match my mosfets from myself...I would learn to do it!
Here you are!
This it's what I have understood about matching IRPF240 for Aleph 30.
Does it is correct?
Well...
Do I need a specific socket to insert MOSFET or I may connect the cables directly to mosfet pins?
In the schematic that I found on the web regarding matching irfp240 there is not the trimpot. It seems simple as my sketch...
2pico, do not confuse him, his circuit is adequate for task
andrea - you can use molex connector from broken PC PSU
andrea - you can use molex connector from broken PC PSU