I was going to ask same question, I guess i'll touch it to MOSFET plastic/ceramic, not the washer or bolt
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Is there a BOM (with actual part numbers from mouser/digikey/etc...) available for the power supply above? There doesn't seem to be anything like this available, even in the thread about building the universal power supply. The specific resistors and caps would also be helpful because there are many variants and in some cases, its unclear that they'll work ok in the circuit.
Also a suggestion to the diystore folks that create the F5 parts kit -it would be awesome if you guys could create a similar one for the F5 power supply that matches one of the build guides. I've gone over all of the PS and build threads now twice, and this is one of the most confusing things I've found because the power supplies have evolved and its hard to tell where a good, fixed point is to start.
Also a suggestion to the diystore folks that create the F5 parts kit -it would be awesome if you guys could create a similar one for the F5 power supply that matches one of the build guides. I've gone over all of the PS and build threads now twice, and this is one of the most confusing things I've found because the power supplies have evolved and its hard to tell where a good, fixed point is to start.
I have also starting digging about power supplies. I would love to mimic the one in the F7 which has more capacitance (less noise?), but then I read about a pseudo dual power supply in another thread. I am equally as confused.
It's really basic:
8 15,000UF 25V electyrolytics
8 .47ohm 3W
2 2.2K 3W
2 35A bridges
3 thermisters
And a safety cap, fuse, switch, transformer. No need to modify it. I can dig up some part numbers.
8 15,000UF 25V electyrolytics
8 .47ohm 3W
2 2.2K 3W
2 35A bridges
3 thermisters
And a safety cap, fuse, switch, transformer. No need to modify it. I can dig up some part numbers.
Thermisters:
SL15 60002 Ametherm | Mouser
Also two more resistors and 2 LEDs mentioned in the build guide.
SL15 60002 Ametherm | Mouser
Also two more resistors and 2 LEDs mentioned in the build guide.
I would not go with the Nichicon caps as suggested above for the PSU. There are cheaper options and I have heard of a famous and generous amp designer who possibly uses caps like these sometimes:
SLPX PSU caps
PSU resistors if you can find them are the Panasonic 3W
0.47R(ohm)
Mouser seems to be out of stock (in Canada) of the 2.2K ERG/X/S and so does Digikey but Mouser has a bunch on order
2.2K
There is the original FW PSU prior to the F7 and then with the F7 the capacitors on the second half of the CRC get split for left and right. Maybe you could be the person who will hear a difference but if you cannot source this pseudo dual rail PSU (or whatever the correct term is) then don't worry about it.
For beginners, if ever in doubt, buy the store board and follow the excellent build guide by 6L6.
SLPX PSU caps
PSU resistors if you can find them are the Panasonic 3W
0.47R(ohm)
Mouser seems to be out of stock (in Canada) of the 2.2K ERG/X/S and so does Digikey but Mouser has a bunch on order
2.2K
There is the original FW PSU prior to the F7 and then with the F7 the capacitors on the second half of the CRC get split for left and right. Maybe you could be the person who will hear a difference but if you cannot source this pseudo dual rail PSU (or whatever the correct term is) then don't worry about it.
For beginners, if ever in doubt, buy the store board and follow the excellent build guide by 6L6.
I am definitely going with the DIYStore boards for my F5 and F6 builds. Thank you for the recommendations. After I assemble mine and get them working, I'll post the BOM so others can click/purchase the parts on Mouser making it a snap for newbies. 🙂
The other thing I want to experiment with is the CLC versus CRC type of power supply. If others have tried this, it would be great to discuss and hear about your results.
There are a few folks on other forums that have tried this with one guy showing a 20x ripple reduction and claiming it affected the audio in positive ways. Worth experimenting with. That is what all of this stuff is about! 🙂
There are a few folks on other forums that have tried this with one guy showing a 20x ripple reduction and claiming it affected the audio in positive ways. Worth experimenting with. That is what all of this stuff is about! 🙂
20x reduction? That makes me wonder what was wrong with his first version...
That said, CLC is worth trying, but build it CRC first.
As for specific capacitors, the most important thing is you getting ones with the proper leads, which are “10mm snap-in”. Aside that, for PSU filter capacitors, a good generalization is to buy the one with the biggest can, as it’s going to have the best ripple rating. The PCB can accept up to 35mm diameter, but height is rarely an issue in the chassis commonly used.
Grossly over sizing your filter caps will make your bridge conduction angle very low and possibly make for more transformer noise, so stick to something in the ballpark of 15000-22000uF per cap. Nelson’s built amps all use 15000uF and 300VA transformers. Bigger transformers make essentially no difference, except that your amp weighs more. 😀 Shielded transformers are beneficial. The AS- series from Antek, for instance, has a shield whereas the AN- series doesn't.
Higher voltage rating is good, if you can get cans that fit the PCB, as is 105C rating - both these items will increase the life of the capacitors, but dont get hung up on the 105C, as it’s rare in the values we are looking for.
I’ve used caps from Panasonic, Nichicon, Cornell-Dublier, Rubycon, Elna, and Vishay. There’s no difference as far as I can tell. Good caps from reliable sources are all great.
That said, CLC is worth trying, but build it CRC first.
As for specific capacitors, the most important thing is you getting ones with the proper leads, which are “10mm snap-in”. Aside that, for PSU filter capacitors, a good generalization is to buy the one with the biggest can, as it’s going to have the best ripple rating. The PCB can accept up to 35mm diameter, but height is rarely an issue in the chassis commonly used.
Grossly over sizing your filter caps will make your bridge conduction angle very low and possibly make for more transformer noise, so stick to something in the ballpark of 15000-22000uF per cap. Nelson’s built amps all use 15000uF and 300VA transformers. Bigger transformers make essentially no difference, except that your amp weighs more. 😀 Shielded transformers are beneficial. The AS- series from Antek, for instance, has a shield whereas the AN- series doesn't.
Higher voltage rating is good, if you can get cans that fit the PCB, as is 105C rating - both these items will increase the life of the capacitors, but dont get hung up on the 105C, as it’s rare in the values we are looking for.
I’ve used caps from Panasonic, Nichicon, Cornell-Dublier, Rubycon, Elna, and Vishay. There’s no difference as far as I can tell. Good caps from reliable sources are all great.
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Thanks for the advice on the caps. I am looking at these having used them before for another project. I have used the comparable Panasonics before too with success but they don't seem to be available:
SLP223M035H9P3 Cornell Dubilier - CDE | Mouser
These are 108C rated, low-ESR 35V 22000 uF so that should do. I got an ANTEK AN-6218 for the F5 as the smaller 500Va wasn't available and it was minimally more. I looked for the shielded version but it wasn't obvious. Future upgrade I guess! 🙂
SLP223M035H9P3 Cornell Dubilier - CDE | Mouser
These are 108C rated, low-ESR 35V 22000 uF so that should do. I got an ANTEK AN-6218 for the F5 as the smaller 500Va wasn't available and it was minimally more. I looked for the shielded version but it wasn't obvious. Future upgrade I guess! 🙂
Just ordered the F5 and PSU PCB's for my first Pass build.
I'll probably go with the Deluxe 4U chassis because of back panel and UMS but visually prefer a deep 3U...
A few questions:
1) I see alot of folks go with 22kuf and 400VA transformers but if Nelson uses 15k and 300VA is there anything to gain?
2) Regarding power tx orientation, this guide has it horizontal but in the DIY guide its mounted on the front panel.. any preference?
3) PSU schematic shows 2.2K 3W. bleeder but the DIY guide has 10K. Doesn't matter?
Thanks!
1) Not really. But if making it bigger makes you happy, go for it. 😀
2) Depends on where you need the room. I'm starting to really like horizontal just because it makes the 300mm deep feel much bigger.
3) Nope.
2) Depends on where you need the room. I'm starting to really like horizontal just because it makes the 300mm deep feel much bigger.
3) Nope.
What are the recommended wire gauges for:
- IEC -> terminal strip
- bridge -> PSU
- PSU -> F5 boards
- F5 -> output
Thanks!
- IEC -> terminal strip
- bridge -> PSU
- PSU -> F5 boards
- F5 -> output
Thanks!
I use 16AWG for all of the above on FirstWatt-size amps.
(I use 12AWG for the latter 3 on something hefty like an F5 Turbo V3 or Jam Jar.)
(I use 12AWG for the latter 3 on something hefty like an F5 Turbo V3 or Jam Jar.)
Its important to understand that it is ok to go with a size or two bigger on the transformer (same secondary voltage) and caps (35V or higher) without any issue, which is important to understand if you go to get those parts and the exact versions from Pass's recommendations are not available.