I have no plans to get any more A-40 boards. I have built enough A-40, Alephs, Aleph-X and Zens for a while. There is a new project coming up that needs my attention.
Well maybe a Zen V9 if the boards get done soon.
Well maybe a Zen V9 if the boards get done soon.

Wow - I guess I'm really confused now - glad I asked. No boards, no parts list, no amps, and no support.
Chris
Chris
POPBUMPER said:Wow - I guess I'm really confused now - glad I asked. No boards, no parts list, no amps, and no support.
Chris
I have sent you the files, schematic, parts list from a working prototype. This is DIY. It takes some work on your part.
I think this is a nice amp. If I had extra boards I would send them. Sorry.
There are plenty of nice amps to build that would be easier. It is up to you what you want to build. I would start with a Zen V4. There are boards and well documented instructions.
😀
Mike, What's up your sleeve that is requiring so much attention?
I hope your basement is OK🙁
So far..so good for me.....
I hope your basement is OK🙁
So far..so good for me.....
Mike:
So that I'm clear - by DIY, you mean:
1) Get the boards fabbed yourself (OK, no problem)
2) Buy parts using a parts list that does not match the schematic
3) Use a schematic that has "??" as entries for values
If this is the case, then this truly IS DIY. What confounds me, take it as you may, you are also telling me that you have built these amps complete, and have no accurate documentation. You are willing to "share" these designs with the world, and will supply an inaccurate documentation set and schematic so people can build the amps, but without all the info.
If I am wrong anywhere here, please let me know - repeated requests via the group here and private email have gotten me, partial information. You seem willing to help, but I can't get concrete answers.
So, once again, just to confirm, IF this is what you meant by DIY, tell me. I assumed everything would be complete and accurate - but I guess I am wrong in this case. Given nobody else has stepped up and said anything pro or con, it means nobody else has built this, they gave up and didn't complain, or you were more willing to share what you had with them.
Chris
So that I'm clear - by DIY, you mean:
1) Get the boards fabbed yourself (OK, no problem)
2) Buy parts using a parts list that does not match the schematic
3) Use a schematic that has "??" as entries for values
If this is the case, then this truly IS DIY. What confounds me, take it as you may, you are also telling me that you have built these amps complete, and have no accurate documentation. You are willing to "share" these designs with the world, and will supply an inaccurate documentation set and schematic so people can build the amps, but without all the info.
If I am wrong anywhere here, please let me know - repeated requests via the group here and private email have gotten me, partial information. You seem willing to help, but I can't get concrete answers.
So, once again, just to confirm, IF this is what you meant by DIY, tell me. I assumed everything would be complete and accurate - but I guess I am wrong in this case. Given nobody else has stepped up and said anything pro or con, it means nobody else has built this, they gave up and didn't complain, or you were more willing to share what you had with them.
Chris
I built the A40s.
AND i got the boards from Mike, AND he and Jam gave all the info i needed to construct them. AND Mike even sent me the boards for free.
Jam also posted on the question mark components, there is no need for them.
AND Mike even emailed me the Gerber files last week without me asking him.
Both Mike and Jam are part of the nice guys here who just see this as a fun hobby, and it's a shame Jam isn't around anymore.
You're crossing the line, Chris.
I also have the files of the original Mosfet A40 design, done by Norman Thagard, and planning to construct his version as well to see how they both compare. Having the schematic and parts list of the Thagard A40 is enough for me. The board Mr Thagard made sucks so i'll make my own. Of course this is DIY.
AND i got the boards from Mike, AND he and Jam gave all the info i needed to construct them. AND Mike even sent me the boards for free.
Jam also posted on the question mark components, there is no need for them.
AND Mike even emailed me the Gerber files last week without me asking him.
Both Mike and Jam are part of the nice guys here who just see this as a fun hobby, and it's a shame Jam isn't around anymore.
You're crossing the line, Chris.
I also have the files of the original Mosfet A40 design, done by Norman Thagard, and planning to construct his version as well to see how they both compare. Having the schematic and parts list of the Thagard A40 is enough for me. The board Mr Thagard made sucks so i'll make my own. Of course this is DIY.
Chris,
At the time I build the AlephX, we had a massive AlephX thread, a ‘High Power AlephX’ thread, countless other threads that made the project grow but nothing was really carved in stone; no spreadsheet to calculate the amplifier parameters, no WIKI, almost no finished projects, just an enormous amount of posts where people exchanged ideas and prototypes. I didn’t follow the A40 thread enough to know if enough info is here to build something.
But why not get paper and pencil, start calculating (I’m really bad with math 🙂 ) grab all info you can find, start a project and post your findings and troubles? Believe me, it’s very rewarding.
/Hugo 🙂
At the time I build the AlephX, we had a massive AlephX thread, a ‘High Power AlephX’ thread, countless other threads that made the project grow but nothing was really carved in stone; no spreadsheet to calculate the amplifier parameters, no WIKI, almost no finished projects, just an enormous amount of posts where people exchanged ideas and prototypes. I didn’t follow the A40 thread enough to know if enough info is here to build something.
But why not get paper and pencil, start calculating (I’m really bad with math 🙂 ) grab all info you can find, start a project and post your findings and troubles? Believe me, it’s very rewarding.
/Hugo 🙂
That's all
Chris I'm sorry that's all the information I have. If I have extra boards with my next project I will send you some. As for parts lists, they are not set in stone. You may want to build it differently. All I can give you is what I have built.

Chris I'm sorry that's all the information I have. If I have extra boards with my next project I will send you some. As for parts lists, they are not set in stone. You may want to build it differently. All I can give you is what I have built.

Sorry Jacco:
Though I am GLAD you stepped up, your stepping up in defense is quite meaningless. After all, YOU PERSONALLY were afforded accurate documentation and attention, so your defense of them is natural. Had you been given as little, or received incomplete/half answered responses, I DOUBT you would have so willingly went to bat.
Do you not step over the line by criticising my questioning? I guess not, since you got what you wanted - so WHY would you care about anyone else's situation? After all, you got boards for free - I got incomplete information for the asking. Guess you are the lucky one!!
It is obvious that I asked for, and apparently expected far too much. In an everyday world of engineering where I work to be sure that project documentation is 100% accurate, I would >hope< that others involved in engineering disciplines would do the same. I mean, if you PERSONALLY built something yourself, and you were proud of it, and you wanted to share it with others, you would take the time to be sure the info you supplied was accurate and complete, no? You would want to answer questions with care and consideration, no?
OF COURSE NOT. There, that MIGHT have been stepping over the line. Feel free to let me know.
Chris
Though I am GLAD you stepped up, your stepping up in defense is quite meaningless. After all, YOU PERSONALLY were afforded accurate documentation and attention, so your defense of them is natural. Had you been given as little, or received incomplete/half answered responses, I DOUBT you would have so willingly went to bat.
Do you not step over the line by criticising my questioning? I guess not, since you got what you wanted - so WHY would you care about anyone else's situation? After all, you got boards for free - I got incomplete information for the asking. Guess you are the lucky one!!
It is obvious that I asked for, and apparently expected far too much. In an everyday world of engineering where I work to be sure that project documentation is 100% accurate, I would >hope< that others involved in engineering disciplines would do the same. I mean, if you PERSONALLY built something yourself, and you were proud of it, and you wanted to share it with others, you would take the time to be sure the info you supplied was accurate and complete, no? You would want to answer questions with care and consideration, no?
OF COURSE NOT. There, that MIGHT have been stepping over the line. Feel free to let me know.
Chris
Mike:
Sorry for being "hot"....I just felt like you were giving me "half answers", and I was bothering you. As I said, I was pretty excited to do this, but truth is - I would just be bothering you guys a LOT more with incomplete info, and why would I want to do that? I am glad to know you guys have been generous and giving with this project, congrats on your abilities. I hit this thread at the wrong time, with too many expectations, and now I get guys like Jacco giving me flack because I expressed my concerns. I'll shut up about it now.
All the best,
Chris
Sorry for being "hot"....I just felt like you were giving me "half answers", and I was bothering you. As I said, I was pretty excited to do this, but truth is - I would just be bothering you guys a LOT more with incomplete info, and why would I want to do that? I am glad to know you guys have been generous and giving with this project, congrats on your abilities. I hit this thread at the wrong time, with too many expectations, and now I get guys like Jacco giving me flack because I expressed my concerns. I'll shut up about it now.
All the best,
Chris
Hugo:
I am happy it went that way with the Aleph - as an engineer, I embrace that premise that everything has to be "right", "clean", "accurate". I work building PCB's every day, and believe me you, as one of the guys that scrubs and defines board builds, its hard to divorce myself from this. The fact that these amps were built "told me" every "I" was dotted, and every "T" was crossed. Not so, lesson learned. I will sit back and watch the show.
Chris
I am happy it went that way with the Aleph - as an engineer, I embrace that premise that everything has to be "right", "clean", "accurate". I work building PCB's every day, and believe me you, as one of the guys that scrubs and defines board builds, its hard to divorce myself from this. The fact that these amps were built "told me" every "I" was dotted, and every "T" was crossed. Not so, lesson learned. I will sit back and watch the show.
Chris
Chris, we're not engineers in that sense here. We all like to fiddle. If you look at almost every project on these forums, virtually everyone has built it differently. Even if you look at slightly more developed projects like MikeB's Symasym, or the Krell project I am involved in, the permutations are endless. Nothing is set in stone. There are very well developed amps in the Pass forum if that's what you want, just visit Nelson's site for very good info.
However, the great thing about these forums is that we do have cutting edge design going on, with very informal project groups getting together to develop new ideas. Once the concept is proven, a lot of people get bored, and move on to the next idea, rather than nailing every single component and layout issue, which are often optimised for each individual's system anyway. Just relax, and enjoy the ride. Oh and if you do want to build a class A monster, the Krell Clone project might be worth a look. 😉
However, the great thing about these forums is that we do have cutting edge design going on, with very informal project groups getting together to develop new ideas. Once the concept is proven, a lot of people get bored, and move on to the next idea, rather than nailing every single component and layout issue, which are often optimised for each individual's system anyway. Just relax, and enjoy the ride. Oh and if you do want to build a class A monster, the Krell Clone project might be worth a look. 😉
Hi Chris,
As pinkmouse mentioned, you will even see compensation changes for different transistor types. Some of these designs are truly bleeding edge with another revision coming out before you can finish building yours. That's part of the fun.
Besides, many commercial audio amplifiers have a clause stating that the design is subject to change to improve performance (or whatever suits the manufacturer). You would call it an engineering change order.
Come on, get a little dirty. 😉
-Chris
As pinkmouse mentioned, you will even see compensation changes for different transistor types. Some of these designs are truly bleeding edge with another revision coming out before you can finish building yours. That's part of the fun.
Besides, many commercial audio amplifiers have a clause stating that the design is subject to change to improve performance (or whatever suits the manufacturer). You would call it an engineering change order.
Come on, get a little dirty. 😉
-Chris
Thanks for the comments guys. BTW, where do I find this "Krell Clone" info? I'll go bother someone else...! I'm ready to build!
Chris
Chris
http://www.diyaudio.com/forums/showthread.php?s=&threadid=31077
Mark has boards.
And better parts lists.
Mark has boards.

And better parts lists.
MikeW said:
I may take a couple of weeks of listening.
I agree with the idea.
I see many people are fond of bass at shop and for few days at home so that they forget how good music is. I think the verification of (subjective) sound quality requires certain time, not by instant A/B tests, IMHO.
Regards
Chris,
my intention was merely to answer your question, not to start a browl.
All of the information needed to build the Mosfet A40s is given on the 10 pages of this thread.
You are right that it is not a complete and accurately documented package, as preferred by an engineer.
Most engineers in my proximity don't even come close to my level of detail, half of them just write perfectly documented reports containing fundamental errors.
I can't imagine Mike to be an engineer, judging from the contraptions he constructs. And maybe Jam, who designed the Mosfet A40, is not one either.
The boards i got from Mike, as a present, miss part of the silkscreen, stuffing the first board took me a bit of time. To make sure i did not make a mistake i compared all component connections with the schematic and followed each trace, luckily the Mosfet A40 circuit is a simple one.
All of the documentation needed to construct Mosfet A40s is still available on these 10 pages and you have the gerbers, if you are employed in the PCB fabrication business it should be easy to have some boards made.
Making a complete parts list from the schematic takes just 5 minutes.
With exception of the design and the boards i've constructed everything myself, as you can see from the pictures i have posted on this thread. There are a number of choices that can be made for the Mosfet A40 design. I still need to complete the voltage regulators for the front end of the amplifiers and install them. This week i hope to exchange the IRFP9240 output devices by IRFP9140s that finally arrived.
That is how i see engineering. To some my way resembles fanaticism, others find it admirable. Fortunately this place is filled with people who think alike, and my partner and family members see me as exceptional.
Getting a few boards made or making them yourself, and making a parts list, is the smallest part of the project.
On the KSA50 thread you can find all the information you need to construct one, and more. And everything is well documented. All it takes is to read +600 pages, not 10.
my intention was merely to answer your question, not to start a browl.
All of the information needed to build the Mosfet A40s is given on the 10 pages of this thread.
You are right that it is not a complete and accurately documented package, as preferred by an engineer.
Most engineers in my proximity don't even come close to my level of detail, half of them just write perfectly documented reports containing fundamental errors.
I can't imagine Mike to be an engineer, judging from the contraptions he constructs. And maybe Jam, who designed the Mosfet A40, is not one either.
The boards i got from Mike, as a present, miss part of the silkscreen, stuffing the first board took me a bit of time. To make sure i did not make a mistake i compared all component connections with the schematic and followed each trace, luckily the Mosfet A40 circuit is a simple one.
All of the documentation needed to construct Mosfet A40s is still available on these 10 pages and you have the gerbers, if you are employed in the PCB fabrication business it should be easy to have some boards made.
Making a complete parts list from the schematic takes just 5 minutes.
With exception of the design and the boards i've constructed everything myself, as you can see from the pictures i have posted on this thread. There are a number of choices that can be made for the Mosfet A40 design. I still need to complete the voltage regulators for the front end of the amplifiers and install them. This week i hope to exchange the IRFP9240 output devices by IRFP9140s that finally arrived.
That is how i see engineering. To some my way resembles fanaticism, others find it admirable. Fortunately this place is filled with people who think alike, and my partner and family members see me as exceptional.
Getting a few boards made or making them yourself, and making a parts list, is the smallest part of the project.
On the KSA50 thread you can find all the information you need to construct one, and more. And everything is well documented. All it takes is to read +600 pages, not 10.
I can't imagine Mike to be an engineer, judging from the contraptions he constructs. And maybe Jam, who designed the Mosfet A40, is not one either.
Thanks, Jocco. I have a BS in mathematics. I do work as an engineer and they do pay me for it.
I have learned a working unit is better than a good documentation package. That is unless you are going to make millions.
Thanks, Jocco. I have a BS in mathematics. I do work as an engineer and they do pay me for it.

I have learned a working unit is better than a good documentation package. That is unless you are going to make millions.
jacco vermeulen said:Half of them just write perfectly documented reports containing fundamental errors.
Are you one of these, Mike ?

- Status
- Not open for further replies.
- Home
- Amplifiers
- Pass Labs
- Mosfet A40