You need to do what I do when I don't know or understand something - I search the internet. If you search "bridge rectifier", you will find the answer. The answer will probably include an explanation of workings of the power supply. For instance:
https://www.electronics-tutorials.ws/diode/diode_6.html
This is only one webpage. There are others. Seek more than one in your research.
I started out with no knowledge, the same as you. Every time I had a question, I did an internet search and I would usually find the answer. If I still did not fully understand, then I would seek clarification.
Either of the two bridge rectifiers will work. One has a maximum voltage rating of 200V and the other has maximum voltage rating of 600V. In this application it will see perhaps 30V maximum, if that.
https://www.electronics-tutorials.ws/diode/diode_6.html
This is only one webpage. There are others. Seek more than one in your research.
I started out with no knowledge, the same as you. Every time I had a question, I did an internet search and I would usually find the answer. If I still did not fully understand, then I would seek clarification.
Either of the two bridge rectifiers will work. One has a maximum voltage rating of 200V and the other has maximum voltage rating of 600V. In this application it will see perhaps 30V maximum, if that.
13stoploss, I totally understand your frustration, but you can finish this as I did. AJ was my very first project and my knowledge level was not too different from yours.
- What's the difference between 3502 and 3506?
Check pdf at Mouser. You can find Maximum Repetitive Reverse Voltage is different between 3502 and 3506, 200V vs 600V. This means 3506 is more robust, but since our PSU only output 20V or so, both perfectly work fine. Bridge rectifier is 4 diodes in one body for convenience. So you can choose either 2 rectifiers attached to the case or 8 diodes soldered on PSU PCB. You don't need both.
You breakup your questions, and someone would answer one by one, don't worry.
- What's the difference between 3502 and 3506?
Check pdf at Mouser. You can find Maximum Repetitive Reverse Voltage is different between 3502 and 3506, 200V vs 600V. This means 3506 is more robust, but since our PSU only output 20V or so, both perfectly work fine. Bridge rectifier is 4 diodes in one body for convenience. So you can choose either 2 rectifiers attached to the case or 8 diodes soldered on PSU PCB. You don't need both.
You breakup your questions, and someone would answer one by one, don't worry.
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I think that the BOM, and the initial build guide, reflect the then current thinking on available parts and how to employ them. It's probably not realistic to hope for a BOM and build instructions that are kept current with the latest and greatest parts suggestions made by subsequent builders over the years in the surprisingly large number of threads devoted to this amplifier.
With regard to the power supply, you will notice that there has been a complete build thread on the newer board, showing alternative constructions depending on whether you want to employ monolithic bridges or discrete diodes.
There's no substitute for doing at least some study and acquiring a basic level of familiarity with the parts involved in a basic Pass power supply, especially when improper construction and implementation can potentially cause problems that extend even to your health. The good(?) thing is that once you've built your first amp, the next three or four are nice and simple.
Good luck with the build - Pat
13stoploss,
Recently a couple members have started on a 'noob guide' for an Aleph-j. The guide
is a work in progress, but you may find it interesting:
DIY Aleph J
Here's the thread with a lot of discussions:
Aleph J build guide for noobs
Good luck with your project.
Dennis
Recently a couple members have started on a 'noob guide' for an Aleph-j. The guide
is a work in progress, but you may find it interesting:
DIY Aleph J
Here's the thread with a lot of discussions:
Aleph J build guide for noobs
Good luck with your project.
Dennis
Yes it is a good idea, an excellent idea to read the entire thing. It isn't as onerous as it seems, much of the posts are just banter.
The first thing you need to do is learn about all the parts used in these builds and be able to identify them. It's strange at first, but it becomes repetitive, and familiarity grows. You also need to be accomplished at proper soldering.
As you read you will have questions, like the bridges you inquired about. This forum is a God send for this hobby, knowledgeable people, ability to post pics, etc. When I first started with tubes, it was all telephone calls and magazines...I didn't even own a computer!
As you read, much is banter you can blow past. As you develop questions about what you are reading and note them by post number for later reference. Same with parts substitutions and new developments, note them by post number also.
Once finished, you have your own guide to use and develop questions. The next build will be much easier, especially power supply as parts are mostly similar across the builds.
Like anything there is a learning curve to getting comfortable. Many come here requesting kits...while some kits have hit the store, most are just core parts.
Read all the build guides, they will keep going over the same sort of builds from different perspectives and pics. Others will have asked the same questions you have, and you can note them and then refer back to it when the answer pops up.
This site really doesn't deal with complete beginner proof kits, with the exception of ACA. Most "kits" have the hard to get stuff, but then you are left to your own knowledge and knowledge of those you ask.
Try to resist a bunch of "improvements" until you have an amp built per the guide. Then ask and try your improvements on a working unit. Otherwise it may be more difficult for others to help troubleshoot.
Last thing, as you read these guides, notice when the members who are extremely knowledgeable answer questions and note their answers by post #.
Your next build will be much more straight forward.
Russellc
If I recall correctly, you were the one who posted in a conversation concerning difficulty of using this sites search function....your answer works quite well, google search and reference DIYAudio in the search terms. I think it was you? Anyway it works well for me!
Great link, BTW.
Russellc
Well, I decided to order 4 of these LKG1V332MESYBK Nichicon | Mouser
I have put around 50 hours of listening in on my amp and at this point, curiosity has gotten the better of me. Perhaps this coming weekend I'll get a chance to pull the PSB out, mount these, reassemble, and set the amp again. I'll be sure to report back.
It's a bummer that we can search 4 letter words but not 3 letter words!
This is the problem not only on this forum.
Google search is easy and real help.
If you want to search for example on diyaudio forum.
Write
And after space put your search interest like this.
Or evern specific in Pass Labs threads.
Well, everybody always build more than one amp, so it's not an altogether crazy idea.
Might as well start collecting parts for M2x as well.
I know, there was an M2x setup w/ an AS-4218 that I came very close to picking up... I'm sure at some point I'll build another.
I have a hard time believing that the AS vs AN transformer is going to be what ruins my audio experience, but if anyone said there was a definite improvement I think I could always find something else to build... Or a super powered preamp.