Have we settled on a best op amp for the output stage yet?
I'm trying to decided which version of the PCB to order
I'm trying to decided which version of the PCB to order
In the ratio sound/price it could be LM6171. Slightly better sounds OPA627 but the price is astronomical. Both are in SMD and DIP. I will suggest the DIP version as it is more versatile - you can easily test another opamp or a custom I/V in the future.
Have we settled on a best op amp for the output stage yet?
I'm trying to decided which version of the PCB to order
Hi
i am very interesting
Where do you order the PCB?
Thanks
Serge
@Sergelisses
PCBs are often ordered from jlcpcb (during checkout select europacket, it is best shipping/price for the EU, or fedex). Alternatively, you can use some local service, but the price will be hardly competitive. See the price for 5pcs including good shipping in the EU.
PCBs are often ordered from jlcpcb (during checkout select europacket, it is best shipping/price for the EU, or fedex). Alternatively, you can use some local service, but the price will be hardly competitive. See the price for 5pcs including good shipping in the EU.
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Any plans to make this available as a kit ? Hate ordering pcb supply components from 10 different places
@Johnsykes
Someone could 😀 But generaly it is a lot of work with kits and is not cheap.
Thanks to a few people who find a motivation for group buys 🙂
All components are easily available from mouser (yeah, except PCB and AD1862)
6x 771-HCT164D652
13x 594-MBB02070Z0000ZCT
3x 594-MBB02070C2209FCT
2x 594-MBB02070C2209FCT
2x 594-MBB02070C2701FCT
6x 80-C320C104K1R
12x 80-R79IC3100Z340J
2x 647-UFG1H4R7MDM
2x 647-UKZ1H470MPM
6x (10x) 667-EEU-FR1E470
8x (10x) 647-UKZ1E101MPM
(2x 80-C1206C470JDGAUTO)
1x 649-1012937891001BLF
(1x 649-1012938190602BLF)
2x 575-1104730841001000
2x 110-47-316-41-001000
(2x 926-LM6171BIN/NOPB)
... moreover, different people prefer different capacitors, opamps, and so it is all the more difficult
... check capacitor packages because in the first PCB version the bigger capacitors are mounted from the bottom (as @Vunce suggested), next PCB versions have more space for bigger capacitors, that is cost of the progress 😀
Someone could 😀 But generaly it is a lot of work with kits and is not cheap.
Thanks to a few people who find a motivation for group buys 🙂
All components are easily available from mouser (yeah, except PCB and AD1862)
6x 771-HCT164D652
13x 594-MBB02070Z0000ZCT
3x 594-MBB02070C2209FCT
2x 594-MBB02070C2209FCT
2x 594-MBB02070C2701FCT
6x 80-C320C104K1R
12x 80-R79IC3100Z340J
2x 647-UFG1H4R7MDM
2x 647-UKZ1H470MPM
6x (10x) 667-EEU-FR1E470
8x (10x) 647-UKZ1E101MPM
(2x 80-C1206C470JDGAUTO)
1x 649-1012937891001BLF
(1x 649-1012938190602BLF)
2x 575-1104730841001000
2x 110-47-316-41-001000
(2x 926-LM6171BIN/NOPB)
... moreover, different people prefer different capacitors, opamps, and so it is all the more difficult
... check capacitor packages because in the first PCB version the bigger capacitors are mounted from the bottom (as @Vunce suggested), next PCB versions have more space for bigger capacitors, that is cost of the progress 😀
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... moreover, different people prefer different capacitors, opamps, and so it is all the more difficult
Indeed so! Some people didn't come into this whole thing thinking that, but it seems to happen anyway. First with the op amps, now I've built a socketed board to test with and managed to get a set of rather esoteric resistors to try in the I/V stage. Just need to put together a new power supply and I can A/B against the first board. Then I can try some of the op amps in the TPA3255 amplifier. Then... then... then...
I blame you all.
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LOL Paddy, you are another true hearted DIY in the forum! It is very valuable for this community 
>>I blame you all.
It is not the end, rather the beginning

>>I blame you all.
It is not the end, rather the beginning

>>I blame you all.
It is not the end, rather the beginning![]()
Exactly right Paddy and Miro!
The chassis for this DAC will have to be convertible, I can’t stop fiddling with it.
A tweak here and a tweak there 😀
Nice socketing there Paddy. Nice idea.
So mine is coming on slowly but the board is soldered now. Moved a few caps to the underside to help clearances.
I have a 'studer900' type psu kicking about that i shall try for the analogue rails. Will sort something cheap and cheerful for the 5v for now. I have some Mark VRDN Denoiser boards to try out aswell as the Salas regs I mentioned earlier but maybe they are overkill here.
And I need to decide on a spdif to i2s board. I will mainly be using a Chromecast Audio. I seem to have lost my enthusiasm for Rpi.
So mine is coming on slowly but the board is soldered now. Moved a few caps to the underside to help clearances.
I have a 'studer900' type psu kicking about that i shall try for the analogue rails. Will sort something cheap and cheerful for the 5v for now. I have some Mark VRDN Denoiser boards to try out aswell as the Salas regs I mentioned earlier but maybe they are overkill here.
And I need to decide on a spdif to i2s board. I will mainly be using a Chromecast Audio. I seem to have lost my enthusiasm for Rpi.
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Hi Paddy,
Can you share the part numbers for your gold plated DIP sockets and also your prototype single sockets you’re using?
I used to have a bag of those single prototype sockets, they are very handy, but I used them up and I cannot find a suitable replacement.
Thanks 🙂
Can you share the part numbers for your gold plated DIP sockets and also your prototype single sockets you’re using?
I used to have a bag of those single prototype sockets, they are very handy, but I used them up and I cannot find a suitable replacement.
Thanks 🙂
Hi Vunce - the DIP sockets are Mouser 575-113308, $1.32 in the US.
I didn't have the patience to shop through all the varieties and sizes of discrete sockets, so the single sockets are a cheat: Mouser 855-D01-9970742 8 pin single inline. I clipped away the plastic around one pin, pushed it out, and moved on to the next. They work pretty well but are a pain to install, since there's nothing to hold the pin straight.
The cheat is cheap, though - the 8-pin piece is 80 cents, so each socket costs a dime.
I didn't have the patience to shop through all the varieties and sizes of discrete sockets, so the single sockets are a cheat: Mouser 855-D01-9970742 8 pin single inline. I clipped away the plastic around one pin, pushed it out, and moved on to the next. They work pretty well but are a pain to install, since there's nothing to hold the pin straight.
The cheat is cheap, though - the 8-pin piece is 80 cents, so each socket costs a dime.
Hi Vunce - the DIP sockets are Mouser 575-113308, $1.32 in the US.
.... I clipped away the plastic around one pin, pushed it out, and moved on to the next. They work pretty well but are a pain to install, since there's nothing to hold the pin straight.....
Hahaha!!
That's exactly what I've doing since I ran out of the proto sockets 😀
Thanks for the DIP socket part numbers.
@Sergelisses
PCBs are often ordered from jlcpcb (during checkout select europacket, it is best shipping/price for the EU, or fedex). Alternatively, you can use some local service, but the price will be hardly competitive. See the price for 5pcs including good shipping in the EU.
Hi miro1360
Do you have and address un EU to order the pcb?
Thanks
Serge
@Sergelisses
Yes, my local address in EU (SK). They can ship to France without problems, I guess.
Yes, my local address in EU (SK). They can ship to France without problems, I guess.
I followed Vunce's mouser project BOM but I seem to be missing the crimp terminals to insert into the white plastic housings. I did my best to research and find them myself but I am a little bewildered!
Any help with the PN please?
Thankyou
Any help with the PN please?
Thankyou
Hi Jim,
Yeah, your right. I don’t have the Molex KK crimps listed, sorry about that🙁
This is the part number: 08-51-0108LP (loose piece)
https://www.mouser.com/datasheet/2/276/0008510108_CRIMP_TERMINALS-156256.pdf
Also, looking back at the thread, I never posted the manufacturing files for the OPA861 I/V output stage boards (inspired by P. Rogic’s Aya II DAC). These boards are 100% SMT with a few parts being tricky to solder for a first time smd project. Here they are with the supporting documentation:
Yeah, your right. I don’t have the Molex KK crimps listed, sorry about that🙁
This is the part number: 08-51-0108LP (loose piece)
https://www.mouser.com/datasheet/2/276/0008510108_CRIMP_TERMINALS-156256.pdf
Also, looking back at the thread, I never posted the manufacturing files for the OPA861 I/V output stage boards (inspired by P. Rogic’s Aya II DAC). These boards are 100% SMT with a few parts being tricky to solder for a first time smd project. Here they are with the supporting documentation:
Attachments
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Thanks Vunce. I found a reference in your BOM for XRKs BTSB but they are out of stock until May so that part number above is very helpful.
Hey I have a question for more knowledgeable people around here... I will start building new amplifier (My_ref) now that the GB is over and I received PCBs and I have a question regarding op-amps since my_ref uses op-amp on input stage. So I was just wondering and have no clue where to start looking for answers, first one that pops in my mind is are there any downsides of using op-amp (output) in this DAC and than going straight to op-amp (input) in my_ref amplifier. I know if this two were a commercial product you would just connect the two and listen. But since this is DIY forum I am just interested if there would be any other (better) way of doing this or some other things to look for, like same or diferent op-amps, or maybe no op-amp in DAC or It will be just fine as is. 😕🙂 Thanks
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