Yes, same PCB - just adjust values as shown. You will have to do a little detective work to translate Hugh's component designations to the ones JP's uses on the PCB silkscreen. But the schematic is the same.
Definitely use FQA for outputs and KSA992 for LTP as pins for 5401 are not compatible. For Q4, either KSA992 or BD140 can be used - same pins.
Definitely use FQA for outputs and KSA992 for LTP as pins for 5401 are not compatible. For Q4, either KSA992 or BD140 can be used - same pins.
D2 and D3 don't appear on the schematic on page one but if that the only additional component that would be simple to tack onto the BJT leads.
Look at the v001 production board schematics in GB thread and you will see the diodes.
Alpha Nirvana 39W SE Class A Amplifier GB
https://www.diyaudio.com/forums/att...-class-amplifier-gb-alpha-nirvana_sch_001-pdf
Alpha Nirvana 39W SE Class A Amplifier GB
https://www.diyaudio.com/forums/att...-class-amplifier-gb-alpha-nirvana_sch_001-pdf
For 4R version I suggest an SLB per channel as 3A draw is too much for sharing with both channels at 6A total. To get +/-20Vdc rails from SLB assuming 3v drop either a 300VA to 400VA 18vac to 20vac trafo is needed per channel. Antek I would get 400VA and 20vac. Toroidy I would get 300VA and 18vac. One sags more than the other. You will need some big heatsinks as this is 40v x 3A is 120W per channel. 5U x 400mm Dissipante can probably do it.
Note that price difference between 300VA and 500VA Antek is peanuts. Go for the dual 500VA to give yourself the least sag and the trafo hums and vibrates less when pulling solid 3A continuously.
Unfortunately, it seems I can't take part in this wonderful race - as I can't even get on my horse! 😱
I clicked on the BoM link provided at the bottom of post #1. Unfortunately, what was downloaded is attached.
I cannot make head nor tail of this list. 🙁
So I'm wondering if anyone has dealt with the BoM successfully and has a readable list of the components that they could send to my email address?
Thanks,
Andy
I clicked on the BoM link provided at the bottom of post #1. Unfortunately, what was downloaded is attached.
I cannot make head nor tail of this list. 🙁
So I'm wondering if anyone has dealt with the BoM successfully and has a readable list of the components that they could send to my email address?
Thanks,
Andy
yea- that Bom's a little densely packed! worst part of a project for me is parts procurement. I love a kit or a mouser cart. I guess some people like hunting parts down on Mouser, not me
Sorry that this has become problematic. In older versions of Excel, it knew that a CSV file extension meant delimitted text file. I think it expects "comma' delimitted and this is semicolon delimitted. Recent modern versions of Excel has become ignorant of CSV, perhaps as a means to forcce people to assimilate to MS's Borg-like expectation that all spreadsheet files shall be .XLSX format. A quick google search of how to import a CSV file into Excel. First, don't "click" on it to open it.
1. Open a new Excel sheet, select the Data tab, then click 'From Text' in the Get External Data group.
2. Browse to the CSV file and select 'Import'.
3. In step 1 of the Import Wizard choose 'Delimited' as the original data type, choose "semicolon".
That should work. Note that there will be a strange A with a hat in front of greek mu for values of caps. Just ignore the A-hat.
You can do a global search and replace of the A-hat with a blank, as I did here. I saved as an .xlsx file (zipped) for you convenience.
Ask, and ye shall receive...
Here is a Mouser shopping cart that has all the parts you need. Courtesy of Zman01 (Thanks, Zman01!). Please do not modify it but save it to your own cart before ordering. If you modify this cart, it will change it for anyone else trying to order from the same cart:
Mouser Electronics
Also note that this BOM/shopping cart is for the 8R version. If someone wants to do the homework of changing out the appropriate resistors as shown in Hugh's schematic and giving us an updated delta-BOM for the 4R version, that would be great. It might be a good thing to buy the resistors for both 8R and 4R, as they are a nominal extra cost (maybe $10 extra) and you have both versions to use at will.
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Thanks very much, X. 🙂
Interesting what you say about the behaviour of older Excel versions. I was sure that:
a) I had previously loaded a .csv file into an Excel s/sheet, and
b) it was comma-delimited ... not semi colon-delimited!
So I was completely discombobulated with what I saw, this time.
I will make the changes for the 4R version and post the result.
Andy
Interesting what you say about the behaviour of older Excel versions. I was sure that:
a) I had previously loaded a .csv file into an Excel s/sheet, and
b) it was comma-delimited ... not semi colon-delimited!
So I was completely discombobulated with what I saw, this time.
I will make the changes for the 4R version and post the result.
Andy
What's the difference between a project and a cart? Don't they both let you order the parts from the BOM? Here is a project version of it.
Mouser Electronics
N.B., the Shopping Cart/Project is for 1 Channel. Double the order for a stereo amp.
Mouser Electronics
N.B., the Shopping Cart/Project is for 1 Channel. Double the order for a stereo amp.
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X,
Yes, with a project, I can choose to put it into my cart or not and also save it for future purchases if need be. One can archive it as well. I have several projects in my project manager and "reordering" particularly with frequently used projects (SLB, etc...) is much easier.
Thanks again!!
Best,
Anand.
Yes, with a project, I can choose to put it into my cart or not and also save it for future purchases if need be. One can archive it as well. I have several projects in my project manager and "reordering" particularly with frequently used projects (SLB, etc...) is much easier.
Thanks again!!
Best,
Anand.
I think you can save a cart as a new project. That’s what I had to do because Zman01 sent me a cart. Just an extra step or two.
Hi X,
On the Mouser project 2nd position there is a Samtec 3 way header for X111 - ADJ around the 22 ohm R113 position. I assume that is for testing to parallel another resistor with the 22 ohm R113.
Is this still needed on the PCB now you show a value of 22ohm for that resistor?
On the Mouser project 2nd position there is a Samtec 3 way header for X111 - ADJ around the 22 ohm R113 position. I assume that is for testing to parallel another resistor with the 22 ohm R113.
Is this still needed on the PCB now you show a value of 22ohm for that resistor?
Power MOSFETs
The BOM lists the IRF MOSFETs, but X also mentioned the FQAs for higher dissipation rating, and I’m not sure what is now recommended for implementations. Are there any advantages to using the bigger FQA MOSFETs for an 8 ohm load? Life expectancy? Sound? My speakers are Joe Rasmussen’s Elsinores with benign, nearly constant 8 ohm impedance, which I enjoy so much that I think it is unlikely that I will switch to other (4 ohm) speakers soon.
The BOM lists the IRF MOSFETs, but X also mentioned the FQAs for higher dissipation rating, and I’m not sure what is now recommended for implementations. Are there any advantages to using the bigger FQA MOSFETs for an 8 ohm load? Life expectancy? Sound? My speakers are Joe Rasmussen’s Elsinores with benign, nearly constant 8 ohm impedance, which I enjoy so much that I think it is unlikely that I will switch to other (4 ohm) speakers soon.