Regarding the list of components, you have the diagram where the values are specified.
You open the site where you buy electronic components and add the necessary ones.
Simple.... 😎 👍🤪
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C0G/NP0 it"s ok in my opinion.
You open the site where you buy electronic components and add the necessary ones.
Simple.... 😎 👍🤪
-------------------------
C0G/NP0 it"s ok in my opinion.
I think I may go with 50v 100nF PPS actually, they are IMHO superior to ceramic caps.Regarding the list of components, you have the diagram where the values are specified.
You open the site where you buy electronic components and add the necessary ones.
Simple.... 😎 👍🤪
-------------------------
C0G/NP0 it"s ok in my opinion
Anyone who can share the LTSpice simulation file?
I want to check mW across the resistors among other things. I have a lot of very nice TH resistors, but some are rated at 125mW. I want to check which positions, if any, those are ok to use. I also want to check a few other things. I can make the schematic myself in LTSpice, but why re-invent the wheel if someone here can share the simulation file. Thanks
I want to check mW across the resistors among other things. I have a lot of very nice TH resistors, but some are rated at 125mW. I want to check which positions, if any, those are ok to use. I also want to check a few other things. I can make the schematic myself in LTSpice, but why re-invent the wheel if someone here can share the simulation file. Thanks
I'm guessing no one has done simulations for this circuit. Oh well, I'll do it when I have the time and the pain isn't too bad 🙂Anyone who can share the LTSpice simulation file?
I want to check mW across the resistors among other things. I have a lot of very nice TH resistors, but some are rated at 125mW. I want to check which positions, if any, those are ok to use. I also want to check a few other things. I can make the schematic myself in LTSpice, but why re-invent the wheel if someone here can share the simulation file. Thanks
I was not complaining. English is not my first language, so I'm sorry if it came across as complaining.
Just didn't want to re-invent the wheel if someone had a simulation file already.
It would take me a lot longer than 20min, maybe I'm not as skilled as you 🙂
Just didn't want to re-invent the wheel if someone had a simulation file already.
It would take me a lot longer than 20min, maybe I'm not as skilled as you 🙂
Actually RJM himself made an LTSpice circuit. Message #1,671I'm guessing no one has done simulations for this circuit. Oh well, I'll do it when I have the time and the pain isn't too bad
So...I spent a few hours measuring the 200 BC327 I have. The BC337, BD139 and BD140 will have to wait until tomorrow. My back could not take any more abuse today 😅
I really like the Peak Atlas DCA75 Pro.
I really like the Peak Atlas DCA75 Pro.
Attachments
Another Sapphire is alive! Finished building this a few weeks ago now. This is the first time I've built something this complex before and I'm quite happy with the result.
One issue I do have is that with IEMs I can hear a constant 60Hz hum that I'm certain is coming from the power supply. If I switch off the power the hum instantly goes away, turn it back on, hum is back. The sound does change with volume and actually gets quieter as a increase the volume. I'm at a loss as to what's going on here?
I attached some progress photos.
Cheers
One issue I do have is that with IEMs I can hear a constant 60Hz hum that I'm certain is coming from the power supply. If I switch off the power the hum instantly goes away, turn it back on, hum is back. The sound does change with volume and actually gets quieter as a increase the volume. I'm at a loss as to what's going on here?
I attached some progress photos.
Cheers
Attachments
I've now measured all my BC327&BC337.
I can get perfect matches within NPN or PNP, not so much NPN-PNP. Advice on this is greatly appreciated.
The BOM also says Hfe 400...none of the 400 transistors I've measured has a Hfe that high. I hope you can read my handwriting 😅
PS. All devices measured with the Atlas DCA75 Pro.
I can get perfect matches within NPN or PNP, not so much NPN-PNP. Advice on this is greatly appreciated.
The BOM also says Hfe 400...none of the 400 transistors I've measured has a Hfe that high. I hope you can read my handwriting 😅
PS. All devices measured with the Atlas DCA75 Pro.
Attachments
It doesn't matter THB. The only thing that will change is the DC offset at the output.Advice on this is greatly appreciated.
I guess I'll use the BC327 w Hfe 322 and the BC337 with Hfe 244. At least they'll be matched NPN and PNP, though not between NPN and PNP 😅
Well, I have now measured ALL the transistors for the Sapphire build.
200ea of BC327&BC337 and an unknown number of BD139&BD140.
I got decent matches for the BD139 and BD140.
Hfe of between 251 and 252 for the 8 TO-126's. I'm ok with that.
200ea of BC327&BC337 and an unknown number of BD139&BD140.
I got decent matches for the BD139 and BD140.
Hfe of between 251 and 252 for the 8 TO-126's. I'm ok with that.
Attachments
Likely a ground loop/earthing issue. The BOM has some recommendations on how to earth the assembly so I would start there. They can sometimes be a little tricky to cure. My test build had a hum issue which turned out to be the temp poor quality volume pot and earthing the metal shell cured it.Another Sapphire is alive! Finished building this a few weeks ago now. This is the first time I've built something this complex before and I'm quite happy with the result.
One issue I do have is that with IEMs I can hear a constant 60Hz hum that I'm certain is coming from the power supply. If I switch off the power the hum instantly goes away, turn it back on, hum is back. The sound does change with volume and actually gets quieter as a increase the volume. I'm at a loss as to what's going on here?
I attached some progress photos.
Cheers
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