Which components to use for pass aleph

[SRMcGee]

mariussuiram82:

I might also be interested; perhaps your supplier could make more enclosures? I'd appreciate the opportunity to contact your supplier.

Regards,
Scott

[AR2]

Originally Posted by mariussuiram82

I already bought the heatsinks. The were made for the aleph 2. So these will be good. The pcb is from kk-pcb. I heard they are good and have pass approval. The The power supply is going to be hard wired. Are there any recommendations about the power supply. brand traffo etc. And is it better to make it bigger than the standart 600 va / monoblock?

600VA is not enough for Aleph 2.
In another thread Zen Mod just posted this Nelson's classic article on power supplies that will give you all answers regarding the power supplies. May favorite line is " One pound of weight for every 2 watts is a good litmus test for evaluating Class A amplifiers. An amplifier weighing less might not be pure Class A."

[zerowaf]

Hello, DIY friend! I'm also interested in those 'sinks! Can You email to me also the adress of the retailer? My Adress is zerowaf@gmail.com
Me Too Got KK pcb-s, but for A5. My Plan Is To Make 2 monos And, Like Papa SAid, Bias The Hell Out Of It.
P.S. Sorry For Bad English!

[VladimirK]

Originally Posted by AR2

You could use anything that you find available. No reason to worry about brands. For resistors use metal film, for power resistors use metal oxide, Alephs do not use any expensive caps, so for feedback (that is the smallest cap in the schematic) use silver mica, and all other caps are aluminum electrolytes.

I would not agree with what you are saying about electrolytes. If one does not put enough attention to them (for instance to input cap, NFB cap, modulated current source cap, and power supply caps), typical consequence is that LM3886 gives more clear sound than Aleph (as I remember this was found also by Peter Daniel). Even if NFB electrolyte or Aleph current source cap is of top quality, decent polyprop shunting cap is appreciated. Few years ago I was discouraged with my Zen4, assembled with no name electrolytes, since it sounded less transparent than LM3886 chip amp. This fact would immediately give rise to a question why do you need those big and expensive aluminium radiators.

[AR2]

Originally Posted by VladimirK

I would not agree with what you are saying about electrolytes. If one does not put enough attention to them (for instance to input cap, NFB cap, modulated current source cap, and power supply caps), typical consequence is that LM3886 gives more clear sound than Aleph (as I remember this was found also by Peter Daniel). Even if NFB electrolyte or Aleph current source cap is of top quality, decent polyprop shunting cap is appreciated. Few years ago I was discouraged with my Zen4, assembled with no name electrolytes, since it sounded less transparent than LM3886 chip amp. This fact would immediately give rise to a question why do you need those big and expensive aluminium radiators.

From Vladimir to Vladimir,

I made several GCs and several Alephs, and I never liked GCs to Aleph. At the beginning they sounded interesting, but when compared A to B Alephs sounded much more natural, where GCs were more on the dry clinical side. Obviously everyone's experience will be different based on their particular set up.

Regarding the parts, the quality of parts, particularly capacitors is important, but in my experience not as critical in Alephs. Here I am talking about circuit itself not PS. Could you improve by using better quality caps - certainly. But if you are beginner and you never build the bigger amp, what do you think is the best advice - to fuss about various caps or to go ahead and build the amp with what you could easily get. Besides if you look at Mouser, they have very good selection, so more or less what you could get there will be quite fine. Looking at Cornel Dublier, or Mallory or Panasonics I do not think you will make bad choice. Now could you improve with Rifa or Epcos or Black Gate, certainly but I guarantee it is not going to be day or night difference. The only fact that makes big difference is if there is a cap in the path of signal or not. There I find that cap quality is of extreme importance and if possible I would always avoid to have a cap at all. As far as I recall Alephs do not have cap in the path of a signal, unless it is at input which is easily removed (as long as you know that there is no DC coming from your source) The best cap is no cap at all and particularly electrolytics are worst caps that could be placed in the path. If you have to have it and you would like to have the best, than use film cap. Now we are talking about few hundred dollars in some cases.

In my mind it is much better to have a pleasure of completed project and than while you are listening start tweaking and exchanging parts. Only in that case we will be able to learn and appreciate better parts and to find out how and if there is a big difference in using exotic or better parts.

Vladimir

[VladimirK]

Originally Posted by AR2

From Vladimir to Vladimir,

I made several GCs and several Alephs, and I never liked GCs to Aleph. At the beginning they sounded interesting, but when compared A to B Alephs sounded much more natural, where GCs were more on the dry clinical side. Obviously everyone's experience will be different based on their particular set up.

Regarding the parts, the quality of parts, particularly capacitors is important, but in my experience not as critical in Alephs. Here I am talking about circuit itself not PS. Could you improve by using better quality caps - certainly. But if you are beginner and you never build the bigger amp, what do you think is the best advice - to fuss about various caps or to go ahead and build the amp with what you could easily get. Besides if you look at Mouser, they have very good selection, so more or less what you could get there will be quite fine. Looking at Cornel Dublier, or Mallory or Panasonics I do not think you will make bad choice. Now could you improve with Rifa or Epcos or Black Gate, certainly but I guarantee it is not going to be day or night difference. The only fact that makes big difference is if there is a cap in the path of signal or not. There I find that cap quality is of extreme importance and if possible I would always avoid to have a cap at all. As far as I recall Alephs do not have cap in the path of a signal, unless it is at input which is easily removed (as long as you know that there is no DC coming from your source) The best cap is no cap at all and particularly electrolytics are worst caps that could be placed in the path. If you have to have it and you would like to have the best, than use film cap. Now we are talking about few hundred dollars in some cases.

In my mind it is much better to have a pleasure of completed project and than while you are listening start tweaking and exchanging parts. Only in that case we will be able to learn and appreciate better parts and to find out how and if there is a big difference in using exotic or better parts.

Vladimir

Thanks, I agree. One should only keep in mind that Aleph always has a critical electrolytic cap in the Aleph current source. This could be Cerafine or Silmic shunted by 2-5uF polypropilene.

[AR2]

Vladimir,
I am glad we found a common ground. Please do not let me discourage you from sharing your expertise and experience, it is certainly appreciated. In the case when we have a new diyer, I always put myself in their shoes and remember how frustrating experience was for the first time ordering parts. A million choices to choose from and no clue on my side what to select and why.
So, if we could narrow the field and bring them closer to the result - the better.
From another stand point not everyone has ether knowledge or opportunity to try all different parts and to learn from that. That is why is great having posts like yours, but I would say rather for advanced users.


Cheers

[mariussuiram82]

Hello to the diy experts.

In my upinion every information is very welkom. I think AR2 very right to say that for a inexperienced diyer the market outthere for diy part is a real circus. It is difficult to get to know what is realy importend/intresting and what is a good thing to have. But on the other hand i like to get the experience from other (most of the time more experienced) diyers, to get the information needed to build the best amp as possible. For exemple a transformator or tyhe mosfets are a bit expensive to tweak afterwarts and tro them away. (Especially when a part is glued to the chassis like a mosfet). Yes you can tweak afterwards. It's ectualy fun to do to get the experiance and knowledge about what it does to the sound. But only when it comes to cheap parts and if it doesnt dammage the amp when tweaking to muchs (burn the pcb or something like that). But when some one knows the amps weak links, like the the size of the power supply for exemple, the irformation is more then welcome. It has to be a ""perfect"" amp. Ore at least as good as the rest of my set. The finished aleph have to compete to the esoteric ai10 and chord electronic spa 1032 that i use. I like to get class b, clas d, and now class a to learn about the differences. Every tip is welcome. Learned a lot so far. Thank you ar2 and vladimirk

[mariussuiram82]

Hello,

I am now going to buy the mosfets. I can buy them matched. Is it importent that all the 24 are matched together. Or can you match 2 groups of 12 mosfets (or 4 x 6 matched fets). The partlist says you can buy eigher irfp240 or 244 (international rectifier). Witch one is better?

[mariussuiram82]

Mosfets and power supply trafo.

One (hopely last) question before i buy all parts for pass aleph 2. I would like to buy 1000 va power trafo's for the power supply. If there are any recommendations here i would realy like to hear them (do other parts change when changing the trafo ratings?). Because there a little expensive. The other question is about the fets. What is the difference between the irfp240 and the irfp244? And MPSA 18 or BC546B? Do they have the same charasteristics-massurements?

Thank you