That's the right attitude. Here is a suggestion for the title:
"My first class A amplifier build: A guide for the fearful clueless newbie"
...still no stock of the back panel hardware tho).
PS You bought my red ACAs from me, so you've got my first project already.
If you don’t want to wait, it’s pretty easy to assemble these pieces independently. You can pickup the rca inputs and binding posts (Daytona work) at Parts Express. You can also find the model number of the switch/fuse holder and purchase along with anything else you need at mouser or digi.
One can successfully build an amp without knowing any of those things (I certainly didn’t
Another thing that helps is reading Nelson’s articles and user guides. Certainly there are many that are over my head, but I’ve found that each time I go back and revisit one, I’m understanding more and more of what’s being said. I still know next to nothing, but I’m learning
All true. I have no electronics training of any sort. All learned here and a couple of other forums.
Learn to id parts.
Get a good solder rig, don't skimp. Same with solder.
Choose amp, read 6l6 portion of guide and ask questions until you can see finished in head, frame questions where you can't.
Read entire guide. Much is banter, skip until you find questions you have addressed, problems and solutions to them and updates and part substitutions. Make notes including post number and note who made it. Some members here are valuable to read! Others, ehhh. If you see me answer, Zenmods answer, and 6l6 answer you can safely ignore mine, unless one of them ( or insert other knowledgeable member) refers to something I asked, and so on.
Russellc
Get all parts and build it. Have clear schematic, with parts checked off. Take clear picks as you go, parts like resistors measured on multimeter, mounted value up.
OK Fred, you are on. I’ll PM you.
Thanks for all the feedback, everybody. This was not intended as a request for advice, but the advice is appreciated. Maybe not the guy accusing me of playing the victim, but most of it was useful. We will need a title. “A guide for the Fearful Clueless Newbie” has a nice Dale Carnegie ring to it. Fred and I will come up with something, eventually, which should make the path to an Aleph J much easier than it currently is.
Thanks for all the feedback, everybody. This was not intended as a request for advice, but the advice is appreciated. Maybe not the guy accusing me of playing the victim, but most of it was useful. We will need a title. “A guide for the Fearful Clueless Newbie” has a nice Dale Carnegie ring to it. Fred and I will come up with something, eventually, which should make the path to an Aleph J much easier than it currently is.
Yep built my first amp in '83 blew the output transistors quite a few times before I finally got it working, it was cobbled together from parts I scrounged from the tip (with the exception of the output transistors which I bought from the local tandy (a number of times
). All I had to go on was a schematic in an electronics magazine, there wasn't even an article, but I perservered and got there in the end. Some pics and the story are here in the ugly amp thread UGLY Looking Amp! - but good working I later built a Kit amp. a 100W / Channel mosfet amp, that was in 1987 and it is still in daily use. later still I did a P2P LM3886, back when people were saying it was too hard to do.
I've actually been putting together a mouser parts list for my BA3. I've had the boards and fets for I'm not sure how long (must be at least five years) and have never got around to actually building it.
I used the store bom, but it's still tricky. You need to check the size on the pcb to make sure what you think you want to order will really fit, voltages are not specified for some parts, and it may not be entirely intuitive what the voltage should be from the schematic. So I can understand some trepidation.
I actually like being able to pick my own parts, but some additional info such as max size (eg diameter for caps) and min voltage rating (it is there for most parts but not some) would definitely be helpful on the store boms. One thing that surprised my on the store BOM was the 1000uF caps, it has them rated at 25V but that is the actual recommended rail voltage if I remember correctly, I decided to go with 35V to be on the safe side, and also because I will probably run it at around 28 - 30V to squeeze out just a little more.
Tony.
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Awesome! Can't wait to see it. Offer stands for any help I can provide.
Even though you're not looking for advice... one last piece. I'd suggest putting the name of the amp in the title. As you've seen, the search function is not great as-is. Without some mention of the Aleph J, I think it will be a bit harder to gain traction.
Have fun!
OK, all you experienced builders, @alanhuth and I are going to be taking you up on your offers for help! You all better be ready!
Look for a separate thread to appear soon. I've got ideas! And, if all goes well, those ideas will result in an Aleph J for @alanhuth and myself, as well as a path for the other noobs! Wish us luck!
Look for a separate thread to appear soon. I've got ideas! And, if all goes well, those ideas will result in an Aleph J for @alanhuth and myself, as well as a path for the other noobs! Wish us luck!
Could not agree more! And if you are budget conscious and don't mind buying used equipment, I recommend one of these: GW Instek GPC-3020 Dual Tracking Power Supply 5V Fixed - with Free Shipping - US | eBay
This is actually a very thought-provoking thread. Thanks for starting it!
I wish it was easier for newbies to get into the hobby. Part of the issue, I think, is that things have changed so much over the years.
When I got curious about electronics as a kid (waaay before the internet), we had Heathkits, Knight Kits, Radio Shack, Lafayette Radio and Allied catalogs, ARRL handbooks, and magazines. Also, electronic devices we much more "approachable". You could open up a TV set and actually figure out how things worked - and how to fix it.
Kids in STEM curricula are probably more excited by robotics and Arduinos then audio electronics, but that's a whole other discussion.
And of course, having a mentor or two could make a huge difference. This forum is great for people providing help, but the amount of information is overwhelming.
I think some of the 6L6 build guides, in conjunction with parts kits from the DIY Store, could easily be expanded to be more newbie oriented, but that takes work (and maybe some folks here would be willing to put that work in). I would look at some Heathkit examples to see how it was done (and done well).
I wish it was easier for newbies to get into the hobby. Part of the issue, I think, is that things have changed so much over the years.
When I got curious about electronics as a kid (waaay before the internet), we had Heathkits, Knight Kits, Radio Shack, Lafayette Radio and Allied catalogs, ARRL handbooks, and magazines. Also, electronic devices we much more "approachable". You could open up a TV set and actually figure out how things worked - and how to fix it.
Kids in STEM curricula are probably more excited by robotics and Arduinos then audio electronics, but that's a whole other discussion.
And of course, having a mentor or two could make a huge difference. This forum is great for people providing help, but the amount of information is overwhelming.
I think some of the 6L6 build guides, in conjunction with parts kits from the DIY Store, could easily be expanded to be more newbie oriented, but that takes work (and maybe some folks here would be willing to put that work in). I would look at some Heathkit examples to see how it was done (and done well).
I have been building stuff since I was a teenager, but I really didn't learn a lot about amplifiers until I started building single ended tube amps about 25 years ago. They don't have a lot of parts and tubes are hard to destroy. Only issue is the high voltages involved, which teaches you to work carefully and use good practices.
What is great about simple circuits is that they are easier to analyze and to build. Also, you can learn a lot about load lines, operating points, and distortion analysis. For me, learning circuit and electrical theory is important. In the end, this will allow you to build and trouble-shoot amps.
Today, if I were to start from scratch, I would probably build Nelson Pass's De-Lite amplifer. It has all the characteristics of the single-ended 2A3 tube amp that I started out with, but without the 300V power supply.
What is great about simple circuits is that they are easier to analyze and to build. Also, you can learn a lot about load lines, operating points, and distortion analysis. For me, learning circuit and electrical theory is important. In the end, this will allow you to build and trouble-shoot amps.
Today, if I were to start from scratch, I would probably build Nelson Pass's De-Lite amplifer. It has all the characteristics of the single-ended 2A3 tube amp that I started out with, but without the 300V power supply.
Fred and I have not actually spoken yet, but we’ve exchanged PMs and we seem to have similar ideas about this project, and neither of us, I think, underestimate the magnitude of the objective. Others have also offered publicly and privately to help out.
The general approach is that we will have a thread similar to this one dedicated to our project. On that thread, as Fred mentioned, we will be soliciting advice and help with specific problems and we will be providing status updates on the project. The project itself will be built with another tool, (Fred is suggesting Blogger, which I’m fine with) that can be randomly edited and updated while maintaining the same structure.
But if more people get involved, I was wondering if maybe there’s another collaboration tool out there that we should consider. They seem to be coming out of the woodwork. We would want to use a tool that’s structured, has version control, and can be edited with suggestions and final versions. It should allow multiple people to contribute non-destructively and asynchronously, and it should also be able to easily embed photos, scans, and videos into the body of the document.
Any suggestions before we get started?
The general approach is that we will have a thread similar to this one dedicated to our project. On that thread, as Fred mentioned, we will be soliciting advice and help with specific problems and we will be providing status updates on the project. The project itself will be built with another tool, (Fred is suggesting Blogger, which I’m fine with) that can be randomly edited and updated while maintaining the same structure.
But if more people get involved, I was wondering if maybe there’s another collaboration tool out there that we should consider. They seem to be coming out of the woodwork. We would want to use a tool that’s structured, has version control, and can be edited with suggestions and final versions. It should allow multiple people to contribute non-destructively and asynchronously, and it should also be able to easily embed photos, scans, and videos into the body of the document.
Any suggestions before we get started?
OK gang, alanhuth and I have started a fresh thread to start gathering information and opinions together to build a new "noobs guide to building an Aleph J."
First question: what multimeter should a noob get to undertake this project? Please contribute answers on the new thread!
First question: what multimeter should a noob get to undertake this project? Please contribute answers on the new thread!
(only just found this) If I was looking to evaluate which DMM to go for from scratch, then I'd give this piece of intel some scrutiny:
Multimeter spreadsheet (38 brands and 210 meters listed) - Page 1
Here's a tip. This piece of kit is pure gold:
https://www.irwin.com/tools/pliers-adjustable-wrenches/self-adjusting-wire-stripper
Freakin' awesome!!
Hope that helps..
Multimeter spreadsheet (38 brands and 210 meters listed) - Page 1
Here's a tip. This piece of kit is pure gold:
https://www.irwin.com/tools/pliers-adjustable-wrenches/self-adjusting-wire-stripper
Freakin' awesome!!
Hope that helps..
Having built over 30 amps I have noticed a few things that worried me when I was new. I have tried to make projects to incorporate these concepts to make construction easier with each new amp I make.
One thing that makes a first project Class A amp easier for a new builder would be one free of adjustments. No fiddling with bias trim pots or even a pot for DC offset. The amp should self bias and regulate to the correct level, its DC output offset should also self regulate or be designed to naturally be close to zero. This is for a DC coupled dual rail Class A amp. Another thing that makes an amp easier to build and less intimidating would be fewer active components, a simple layout with easy to solder parts, no use of expensive or hard to find unobtanium parts, and the ability to use flying leads for the power transistors (precise drilling and tapping of a heatsink to match a PCB mounted MOSFET or BJT is not easy). The added advantage of using flying leads on the power outputs and having them connectorized with high currents quick connects (Molex minifit etc) is that the amp can be changed or upgraded and the MOSFETs and all mounting standoffs are consistent. Thus, the amp PCB can be removed in under 5 minutes and replaced in 5 more minutes. This allows repairs, adjustments to parts, etc. Think of the level of aggravation involved in pulling an amp PCB from a chassis/heatsink with the MOSFETs soldered to the PCB and screwed on tight. It’s an hour operation not minutes. Similarly, all power or speaker wires should be connectorized (Faston tabs etc) to allow quick removal and to reduce mechanical strain in the wires. Soldered flying leads will peel the copper trace off the board if removed and replaced more than a few times.
But the biggest hurdle IMO, is the wiring of mains from the IEC, to the bridge and CRC and associated grounding. A new builder who hasn’t worked with mains 120vac or 220vac etc can feel a lot of trepidation about this. One thing to consider is to use a SMPS “brick” made for 24v at 5A. They sell these for LED lighting. Get ones that have negative isolated from earth ground. Connect two in series and you have instant safe (and quiet if using the right one) and clean +/-24v PSU capable of handling the typical 2.5A bias currents (combined for 2 channels) of a 25w Class A amp.
No lethal exposed voltages.
Later on, graduate to SMPS boxes that require mains connection. Still safer than full toroidal trafos and associated bridges and cap banks.
I hope that helps.
One thing that makes a first project Class A amp easier for a new builder would be one free of adjustments. No fiddling with bias trim pots or even a pot for DC offset. The amp should self bias and regulate to the correct level, its DC output offset should also self regulate or be designed to naturally be close to zero. This is for a DC coupled dual rail Class A amp. Another thing that makes an amp easier to build and less intimidating would be fewer active components, a simple layout with easy to solder parts, no use of expensive or hard to find unobtanium parts, and the ability to use flying leads for the power transistors (precise drilling and tapping of a heatsink to match a PCB mounted MOSFET or BJT is not easy). The added advantage of using flying leads on the power outputs and having them connectorized with high currents quick connects (Molex minifit etc) is that the amp can be changed or upgraded and the MOSFETs and all mounting standoffs are consistent. Thus, the amp PCB can be removed in under 5 minutes and replaced in 5 more minutes. This allows repairs, adjustments to parts, etc. Think of the level of aggravation involved in pulling an amp PCB from a chassis/heatsink with the MOSFETs soldered to the PCB and screwed on tight. It’s an hour operation not minutes. Similarly, all power or speaker wires should be connectorized (Faston tabs etc) to allow quick removal and to reduce mechanical strain in the wires. Soldered flying leads will peel the copper trace off the board if removed and replaced more than a few times.
But the biggest hurdle IMO, is the wiring of mains from the IEC, to the bridge and CRC and associated grounding. A new builder who hasn’t worked with mains 120vac or 220vac etc can feel a lot of trepidation about this. One thing to consider is to use a SMPS “brick” made for 24v at 5A. They sell these for LED lighting. Get ones that have negative isolated from earth ground. Connect two in series and you have instant safe (and quiet if using the right one) and clean +/-24v PSU capable of handling the typical 2.5A bias currents (combined for 2 channels) of a 25w Class A amp.
No lethal exposed voltages.
Later on, graduate to SMPS boxes that require mains connection. Still safer than full toroidal trafos and associated bridges and cap banks.
I hope that helps.
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Lots of brand new diyAudio hobbyists want to build themselves a Nelson Pass designed amp. Many of the amp designs he has released to the public so far, include end-user adjustment potentiometers for bias, offset, H2 amplitude+phase, and so forth. Perhaps these adjustments could be reduced or eliminated through redesign, but then it's not really a clone of a $4000 First Watt amp and it's not really a Nelson Pass design anymore. I don't think it would be nearly as popular.
Most if not all of the PCBs of Nelson Pass amps in the Store, follow the Universal Mounting Specification of PCB mounting hole and transistor mounting hole placement. This is an intentional and deliberate choice to offer new Nelson Pass Amp builders an option, where they aren't required to drill or tap any holes in the heatsink if they prefer not to. The UMS heatsinks mate with the UMS PCBs, by design, and builders need not be machine tool wizards. Just pay extra to for the UMS option and let real machinists do the work.
Most if not all of the PCBs of Nelson Pass amps in the Store, follow the Universal Mounting Specification of PCB mounting hole and transistor mounting hole placement. This is an intentional and deliberate choice to offer new Nelson Pass Amp builders an option, where they aren't required to drill or tap any holes in the heatsink if they prefer not to. The UMS heatsinks mate with the UMS PCBs, by design, and builders need not be machine tool wizards. Just pay extra to for the UMS option and let real machinists do the work.