Pretty much somewhat mirroring what Itsallinmyhead said
No soft start needed with thermistors as the thermistors become the soft start. A thermistor is a device where the resistance changes based on the current going through it. The current heats the thermistor up which in turn reduces the resistance. So a CL60 will have a cold resistance of around 10 ohms which will reduce to less than an ohm once it is running the amp. So the resistance reduces the current surging into the capacitor bank as it takes a second or two for the thermistor to heat up. Make sure you follow the wiring pattern so that each secondary is tied to a thermistor. Also, make sure it is the correct one for your mains voltage.
Both of those links for the resistors look good. I assume it is your location that is making it hard to find them. However, here is another place that has them:
https://www.newark.com/panasonic/erx-3sjr47/resistor-0-47ohm-3w-5-axial/dp/52W8322?st=0.47 panasonic
Toroidy is well-regarded. Their Audio grade transformers are epoxy filled and have a few other tricks implemented to make a quiet transformer. The supremes have all of that plus a big cover that the transformer is put into with the extra space being filled with epoxy or tar or something like that.
If you plan to get into these first watt clone designs by playing with different amp boards, the transformer and power supply is interchangeable between a lot of designs. So having a nice transformer, nice capacitor bank and rectifiers is nice as you can reuse them.
Another thing to look at is the snubber circuit. There is a tool called the Cheapomodo or QuasiModo (you have to build the tool) that you can use to measure the ringing on your transformer with an oscilloscope. You use the tool to measure your transformer ringing and then adjust a trimmer pot to watch the ringing mostly go away. After you snub the ringing with the tool, you simply measure the trimmer pot and place a resistor that is close to that value into the snubber circuit. Most of the time the resistor value is 6 ohms - 20 oums. Get your amp built and take the time to understand everything first.
The snubber circuit isn't necessary but it is beneficial. So you can circle back to this later down the road but make a note of it. You will have to disconnect your transformer from the PSU board and mains to measure things. Also, assuming you are using the DIYaudio PSU board with the rectifier section, you can install the snubber circuit from the bottom.
No soft start needed with thermistors as the thermistors become the soft start. A thermistor is a device where the resistance changes based on the current going through it. The current heats the thermistor up which in turn reduces the resistance. So a CL60 will have a cold resistance of around 10 ohms which will reduce to less than an ohm once it is running the amp. So the resistance reduces the current surging into the capacitor bank as it takes a second or two for the thermistor to heat up. Make sure you follow the wiring pattern so that each secondary is tied to a thermistor. Also, make sure it is the correct one for your mains voltage.
Both of those links for the resistors look good. I assume it is your location that is making it hard to find them. However, here is another place that has them:
https://www.newark.com/panasonic/erx-3sjr47/resistor-0-47ohm-3w-5-axial/dp/52W8322?st=0.47 panasonic
Toroidy is well-regarded. Their Audio grade transformers are epoxy filled and have a few other tricks implemented to make a quiet transformer. The supremes have all of that plus a big cover that the transformer is put into with the extra space being filled with epoxy or tar or something like that.
If you plan to get into these first watt clone designs by playing with different amp boards, the transformer and power supply is interchangeable between a lot of designs. So having a nice transformer, nice capacitor bank and rectifiers is nice as you can reuse them.
Another thing to look at is the snubber circuit. There is a tool called the Cheapomodo or QuasiModo (you have to build the tool) that you can use to measure the ringing on your transformer with an oscilloscope. You use the tool to measure your transformer ringing and then adjust a trimmer pot to watch the ringing mostly go away. After you snub the ringing with the tool, you simply measure the trimmer pot and place a resistor that is close to that value into the snubber circuit. Most of the time the resistor value is 6 ohms - 20 oums. Get your amp built and take the time to understand everything first.
The snubber circuit isn't necessary but it is beneficial. So you can circle back to this later down the road but make a note of it. You will have to disconnect your transformer from the PSU board and mains to measure things. Also, assuming you are using the DIYaudio PSU board with the rectifier section, you can install the snubber circuit from the bottom.
Thanks a lot for all advices !
I've found thoses ERX-3SJR47 :
https://www.components-store.fr/search.html?keywords=++ERX-3SJR47
I've got no answer in speaker protector thread. I don't understood how to place the speaker protector in the Aleph J. What kind of power transformer is needed ?
I've found thoses ERX-3SJR47 :
https://www.components-store.fr/search.html?keywords=++ERX-3SJR47
I've got no answer in speaker protector thread. I don't understood how to place the speaker protector in the Aleph J. What kind of power transformer is needed ?
OK. I assume since you've linked to mouser earlier that you prefer to order from there:
https://www.mouser.fr/ProductDetail/667-ERX-3SJR47A
Currently showing a little under 500 pieces in stock.
Buy a 100 and you're set for many build.
Cheers,
Dennis
https://www.mouser.fr/ProductDetail/667-ERX-3SJR47A
Currently showing a little under 500 pieces in stock.
Buy a 100 and you're set for many build.
Cheers,
Dennis
Every build i've done has used a Toroidy transformer. I've had no complaints w the performance and build quality.@ItsAllInMyHead Thanks, 22k 3W are R9 R10 for PSU, I made a mistake.
@Mikerodrig27 Thanks, No soft start needed if I put thermistors.
What about speaker protectors ?
For 0.47R 3W resistors, I find this. Can I trust with ebay ones ?
https://www.ebay.fr/itm/394490245034?hash=item5bd9736faa:g:bsUAAOSwZ9xj~wCM&amdata=enc:AQAIAAAA4Avlw5vGvLEoN1xlY2YjtvuM1l4IvD0tfjvm0FMxnVElaz30artlK18pq/IpQHrnMJLOtAZSN0Eab7SCKmicLPXNwz017OK/uG9wlnB5g33pavnb4xB8Zdsl2U+ggrnlNv4rLxiJF0yBpl263qLcLlgTrbKagwXu9FZvjyigeCMep1fJhA/AhI35QehWrEtvyOuAiTfvm+cGuwEN0qg+k9bdf4RBqklwyt1sr0a5rRWiyPx2yatJBO/57oIUz+CEZ/s1cKRIagBlgiPCxp3iN89VM94ZWZEf0aeMxlQNcEfe|tkp:BFBM1pbm3IVi
https://composant-electronique.fr/resistance-0-47-ohm-3w-mor03sj047ka19
I will ask questions on PSU soft start and speaker protection threads.
About power transformer, is anyone know Toroidy ones for advice ?
Thanks a lot !
I can’t tell if you have something around Q1A and Q1B to keep them close together. I’ve seen zip ties and or heat shrink used for that.
@Dennis Hui Thanks! I had not found them 
I don't find substitute for this relay (on the speaker protector) with the same size : https://www.mouser.fr/ProductDetail/Omron-Electronics/G5LA-14-CF-DC5?qs=dLWB/tR6aAZ1eRKXXYI8IQ==
I don't find substitute for this relay (on the speaker protector) with the same size : https://www.mouser.fr/ProductDetail/Omron-Electronics/G5LA-14-CF-DC5?qs=dLWB/tR6aAZ1eRKXXYI8IQ==
Well? 🙂
I would be a very, very, very bad dude if i did not now and then recommended this simply very, very fine Aleph J build guide:
https://diyalephj.blogspot.com/?m=1
I would be a very, very, very bad dude if i did not now and then recommended this simply very, very fine Aleph J build guide:
https://diyalephj.blogspot.com/?m=1
Good stuff. I don't know where you are in your DIY journey or how much electronics parts knowledge you have. So, I won't presume. For me, finding substitute parts is still one of my least favorite activities. I still don't know what specs are important in certain applications for certain parts. So... it can be challenging. The people in the forums are usually incredibly helpful. I'm surprised no one has answered you yet in the other thread. Here's what I recommend.
First, always list the original part number. A link to the spec sheet or providing key data within your post is very helpful and saves other people some work. They'll be more likely to jump in and help if it takes them less time to review your information.
Example - What is the original manufacturer's part number you are trying to find a substitute for?
In post #9288 the link shows .... G5LA-14-CF-DC5. I don't think (from memory, but I could be wrong) that is the correct part.
I think the original part was a 24V relay like G5LA-14-CF-DC24. I didn't have time to look that up until this morning (my time). I checked the posted BoM from the sales page. Yes, it is a 24V relay. However, BoMs get old... is that the latest recommended part?
Then... you can use the awesome Mouser tool (if it pops up). See the Possible Replacement window? It will be on the right side of your page. Then, click the "Compare with Current Part" button?
It will give you ... this ...
I'd then go into the spec sheet for the original part and find the dimensions (comparing cubic to miniature form factors). If they match, then you know it will fit the PCB as a 'drop in'. If not, you can check the board dimensions / outline etc. or ask in the forum.
Also, you could ask some thoughtful questions like if the electrical differences in spec will make a meaningful difference in the circuit.
You'll then learn a bit about what matters in the specs for that particular part for that application. It can be both fun and frustrating. For me... it's still frustrating, but ... that's DIY sometimes.
Good luck!
Edited to add - I popped over to the other thread and did a quick search. I found this post very useful. I found it in response to an inquiry from @myleftear who had the same question as you....
The search function is very useful... Post #407 Gives a nice answer to the question asked in post #442
First, always list the original part number. A link to the spec sheet or providing key data within your post is very helpful and saves other people some work. They'll be more likely to jump in and help if it takes them less time to review your information.
Example - What is the original manufacturer's part number you are trying to find a substitute for?
In post #9288 the link shows .... G5LA-14-CF-DC5. I don't think (from memory, but I could be wrong) that is the correct part.
I think the original part was a 24V relay like G5LA-14-CF-DC24. I didn't have time to look that up until this morning (my time). I checked the posted BoM from the sales page. Yes, it is a 24V relay. However, BoMs get old... is that the latest recommended part?
Then... you can use the awesome Mouser tool (if it pops up). See the Possible Replacement window? It will be on the right side of your page. Then, click the "Compare with Current Part" button?
It will give you ... this ...
I'd then go into the spec sheet for the original part and find the dimensions (comparing cubic to miniature form factors). If they match, then you know it will fit the PCB as a 'drop in'. If not, you can check the board dimensions / outline etc. or ask in the forum.
Also, you could ask some thoughtful questions like if the electrical differences in spec will make a meaningful difference in the circuit.
You'll then learn a bit about what matters in the specs for that particular part for that application. It can be both fun and frustrating. For me... it's still frustrating, but ... that's DIY sometimes.
Good luck!
Edited to add - I popped over to the other thread and did a quick search. I found this post very useful. I found it in response to an inquiry from @myleftear who had the same question as you....
The search function is very useful... Post #407 Gives a nice answer to the question asked in post #442
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@ItsAllInMyHead
Thank you for your answer and your explanations.
I use a translator, I hope to express myself in an acceptable way.
Thank you for your answer and your explanations.
I use a translator, I hope to express myself in an acceptable way.
If I choose this relay :
https://www.mouser.fr/ProductDetail/653-G5LE-1-DC5
Can these transformers fit?
https://sklep.toroidy.pl/en_US/p/TTH0020-Transformer-TS-20VA-23012V-H/186
https://sklep.toroidy.pl/en_US/p/TTSA0020-Transformer-AUDIO-TSA20VA-voltage-to-50V/303
Is it necessary to take an "audio grade" to power the speaker protection board?
Thank you very much.
https://www.mouser.fr/ProductDetail/653-G5LE-1-DC5
Can these transformers fit?
https://sklep.toroidy.pl/en_US/p/TTH0020-Transformer-TS-20VA-23012V-H/186
https://sklep.toroidy.pl/en_US/p/TTSA0020-Transformer-AUDIO-TSA20VA-voltage-to-50V/303
Is it necessary to take an "audio grade" to power the speaker protection board?
Thank you very much.
^ Your English and your expression are perfect to me.
I have never built these... but... until someone much smarter than I jumps in, I will try.
My very limited advice would be to power your speaker protection boards from the same supply as your amplifier boards. No need for a separate transformer. Since the Aleph J uses a ~24VDC supply, I would choose the 12V relays.
This is a nice little diagram of how you could do it. Post #69
https://www.diyaudio.com/community/...ector-board-set-v3.247279/page-4#post-4112491
Please confirm in the appropriate thread with someone with direct knowledge... and that has built it successfully. As mentioned, I have never built this, and I could be looking at it all wrong and/or at outdated information.
Then... after you know generally what you need, choose the correct substitute parts.
Hope that helps.
I have never built these... but... until someone much smarter than I jumps in, I will try.
My very limited advice would be to power your speaker protection boards from the same supply as your amplifier boards. No need for a separate transformer. Since the Aleph J uses a ~24VDC supply, I would choose the 12V relays.
This is a nice little diagram of how you could do it. Post #69
https://www.diyaudio.com/community/...ector-board-set-v3.247279/page-4#post-4112491
Please confirm in the appropriate thread with someone with direct knowledge... and that has built it successfully. As mentioned, I have never built this, and I could be looking at it all wrong and/or at outdated information.
Then... after you know generally what you need, choose the correct substitute parts.
Hope that helps.
Hello,
For the speaker protection board power supply, can someone confirm that I can plug it into the secondary of the Aleph J 500VA/18V (or20V?) transformer, does it 'is possible ? If so, which relay should I choose :
https://www.mouser.fr/ProductDetail/653-G5LE-1-DC5
https://www.mouser.fr/ProductDetail/653-G5LE-1-DC12
Or maybe this 9VDC one : https://www.mouser.fr/ProductDetail...GAEpiMZZMtSzCF3XBhmW%2B7Dtixo7pgPGPiUWMek1sI=
Or is a separate transformer better?
Thanks everyone.
For the speaker protection board power supply, can someone confirm that I can plug it into the secondary of the Aleph J 500VA/18V (or20V?) transformer, does it 'is possible ? If so, which relay should I choose :
https://www.mouser.fr/ProductDetail/653-G5LE-1-DC5
https://www.mouser.fr/ProductDetail/653-G5LE-1-DC12
Or maybe this 9VDC one : https://www.mouser.fr/ProductDetail...GAEpiMZZMtSzCF3XBhmW%2B7Dtixo7pgPGPiUWMek1sI=
Or is a separate transformer better?
Thanks everyone.
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Not trying to influence you one way or the other, but why do you feel you need a relay-based soft-start and the speaker protection for the Aleph J?
If you decide you really want those functions, and if you're not having much luck getting support for the one you already chose, you could try these. I think you will get immediate answers and you can get them already built for you. I think the speaker protection is only sold pre-built.
https://www.etsy.com/listing/769363...low&ref=sr_gallery-1-2&organic_search_click=1
https://www.etsy.com/listing/932716741/rtr-ssr-speaker-protection-gen23-pair?click_key=4e6a9d73b9ea0f045f6df88e8e998194217e32b6:932716741&click_sum=faf8ec5b&ref=related-2
I have not used these either, and I have no bias one way or the other.
If you decide you really want those functions, and if you're not having much luck getting support for the one you already chose, you could try these. I think you will get immediate answers and you can get them already built for you. I think the speaker protection is only sold pre-built.
https://www.etsy.com/listing/769363...low&ref=sr_gallery-1-2&organic_search_click=1
https://www.etsy.com/listing/932716741/rtr-ssr-speaker-protection-gen23-pair?click_key=4e6a9d73b9ea0f045f6df88e8e998194217e32b6:932716741&click_sum=faf8ec5b&ref=related-2
I have not used these either, and I have no bias one way or the other.
Understood... Like I said, I've never built these, and I don't have too much direct knowledge. Perhaps someone else can give you a 'use these parts' direct answer. I cannot.
I know it is particularly hard using a translator, but I would start by reading these two documents and checking the "Ideas and Alternatives" sections.
It can be very hard reading through big threads to find answers. Maybe these will get you started and then someone will be able to help more directly. I do not know if there are later versions of these, but after a brief scan, they look very useful.
https://www.diyaudio.com/media/build-guides/diyaudio-softstart-build-guide-v1.0.pdf
https://www.diyaudio.com/media/build-guides/diyaudio-speakerprotector-build-guide-v1.0.pdf
I know it is particularly hard using a translator, but I would start by reading these two documents and checking the "Ideas and Alternatives" sections.
It can be very hard reading through big threads to find answers. Maybe these will get you started and then someone will be able to help more directly. I do not know if there are later versions of these, but after a brief scan, they look very useful.
https://www.diyaudio.com/media/build-guides/diyaudio-softstart-build-guide-v1.0.pdf
https://www.diyaudio.com/media/build-guides/diyaudio-speakerprotector-build-guide-v1.0.pdf
"For example, if your power transformer has a spare 9VAC or 12VAC secondary winding, choose 6V relay coils for K1 and K2. Or if the spare secondary winding is 18VAC to 24VAC then a 12V relay coil must be used for K1 and K2."
Ok thanks again for your help, I've found this information on the second file attached.
Ok
thanks again for your help, I've found this information on the second file attached.