You said it yourself. Arduino. And point to point breadboard connections. Prototyping. Those are definitely not for production.
Yeah. It's hard to find anything on the market right now. What is better to look for as an alternative?
Direct wire solder is best, followed by ufl connections. I wouldn't bother with anything else for those signals, but you can try some crimped 3x2 connector of required footprint. But in the end it will be faster and best to just resolder wires directly.
There is nothing wrong with pins but you got to make sure of the integrity of the contacts between connectors and pins is good .. and those you are using is not good candidates. And since you mentioned that it is hard for you to find anything on the market, I recommend soldering direct.
The issues that you described , we are quite certain it is the connection problem of the i2s signals or ground itself.
What a thread!! Wealth of information! You guys are responsible for my new obsession with AD1862 DAC. 🙂 Seriously, big thank you to Miro and all contributors for the information, inspiration, and the spirit of the conversation!
This hobby used to be my obsession for many years, but I took a break for the last several years. Few weeks ago, I set up streaming for my old PS Audio DAC with Ian's FiFo and RPi - this DAC never sounded so good. However, it is still fatiguing and it prompted me to look for a new DAC. Obviously, I considered Ian's DAC. But then I came across this thread and you know, it happens to the best of us… 🙂
After a week of reading this thread, I bought AD1862 from Rochester and V 1.3 pcbs from JLCPCB. I should have 4 extra DAC chips next week and a few extra PCBs (2mm, ENIG). If you need a pair of DAC chips or a PCB- send me a PM. Pair of DACs is $50 - Rochester cost - plus shipping.
I am planning to feed DAC from Ian's FiFo Q7II. I know it's probably overkill, but I already have it.
I still need to decide on PSU and IV. My system is tube-based. I mostly listen to vinyl - jazz and classical music. Amp - diy based on 6AC7 (very underrated tube), 6B4G, and Lundahl transformers. Calypso preamp and Quad 57 speakers. My hope is to move away from vinyl as much as possible.
For PSU, I am debating on using Ian's LinearPi and diyinhk. LinearPi allows to use ultracaps, manages on/off status. Anyone has experience with ultracaps - is it worth the trouble? While I appreciate that LinearPi comes pre-built, I would also enjoy soldering a new PSU 2. 🙂 Any thoughts?
I think IV deserves the most attention. My initial thought was to use a transformer and a tube stage, but after reading about CEN/SEN/current mirror I would love to try it. I see that jfets are still available. Is it still possible to buy a folded cascode or any other CEN IV kit? I hope I am not too late to the game.
I went through the entire thread and I would appreciate any advices!
This hobby used to be my obsession for many years, but I took a break for the last several years. Few weeks ago, I set up streaming for my old PS Audio DAC with Ian's FiFo and RPi - this DAC never sounded so good. However, it is still fatiguing and it prompted me to look for a new DAC. Obviously, I considered Ian's DAC. But then I came across this thread and you know, it happens to the best of us… 🙂
After a week of reading this thread, I bought AD1862 from Rochester and V 1.3 pcbs from JLCPCB. I should have 4 extra DAC chips next week and a few extra PCBs (2mm, ENIG). If you need a pair of DAC chips or a PCB- send me a PM. Pair of DACs is $50 - Rochester cost - plus shipping.
I am planning to feed DAC from Ian's FiFo Q7II. I know it's probably overkill, but I already have it.
I still need to decide on PSU and IV. My system is tube-based. I mostly listen to vinyl - jazz and classical music. Amp - diy based on 6AC7 (very underrated tube), 6B4G, and Lundahl transformers. Calypso preamp and Quad 57 speakers. My hope is to move away from vinyl as much as possible.
For PSU, I am debating on using Ian's LinearPi and diyinhk. LinearPi allows to use ultracaps, manages on/off status. Anyone has experience with ultracaps - is it worth the trouble? While I appreciate that LinearPi comes pre-built, I would also enjoy soldering a new PSU 2. 🙂 Any thoughts?
I think IV deserves the most attention. My initial thought was to use a transformer and a tube stage, but after reading about CEN/SEN/current mirror I would love to try it. I see that jfets are still available. Is it still possible to buy a folded cascode or any other CEN IV kit? I hope I am not too late to the game.
I went through the entire thread and I would appreciate any advices!
Hello, lost your message in the jungle...
No, you can't set current draw (and so voltage) from ccs to the tube if there isn't a tube that's drawing current...
For safety and to be sure, just measure that B+ is in the ballpark you expect (around 200V, could be 230, could be 170), then you're set to go
Well, if the usb transport needs to be replaced the soldering will be a problem🙂
I can solder only to the DAC board. So, what kind a plume I must use for better experience?
@Seavan - Contact these members:
@Michelag for 6DJ8 tube IV boards
@woodturner-fran for CEN IV kits.
@abraxalito for the Dark IV.
The CEN boards need some skill but are worth it. The Dark IV is ready to play and excellent. Mike claims the tube IV is best 🙂
My advice is to get the basic DAC working with your input and power supplies using the built in op-amp section, then go to town fella. Build using known quantities first.
@Michelag for 6DJ8 tube IV boards
@woodturner-fran for CEN IV kits.
@abraxalito for the Dark IV.
The CEN boards need some skill but are worth it. The Dark IV is ready to play and excellent. Mike claims the tube IV is best 🙂
My advice is to get the basic DAC working with your input and power supplies using the built in op-amp section, then go to town fella. Build using known quantities first.
Yes, beginn first with an op amp that suit the foot print of the pcb you choose. Read the thread and play with caps & resistors if you want. Listen to it before to swap with I/V stages. I would not go the expensive 627 from Bur brown, there are a lot adviced already in this thread and rank preference it a little the taste of the day from a meal you have not tested yet.
Quality of power supply and power traffos are important too. As the front end. It is a whole where the passive parts also have their role. No easy answers, it is a journey cause you have also to blend it to your whole hifi and personal tastes.
Quality of power supply and power traffos are important too. As the front end. It is a whole where the passive parts also have their role. No easy answers, it is a journey cause you have also to blend it to your whole hifi and personal tastes.
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How on Earth do you measure this? And what good could it do if you know it?
hm.. in theory (and practice) : connecting a most common opamp I/V circuit with known parameters on the Iout pin of the dac, one would obtain a known TIA configuration with an unknown 'Cinput-load' value.
From the obtained / observed noise peaking effect (freq. & amplitude of the peak) -- the input capacity could be calculated.
Like I would do that with a high Rf value, so as to obtain better visible noise floor changes and peaking at lower frequency.
This peaking effect, and the consequent stability criteria are the main reasons for which that Dac output C value could be interesting.
All this becomes less of an importance, if the adviseable Cfeedback parallel capacitance i the I/V circuit gets applied (integrating I/V converter) with a better defined pole
From the obtained / observed noise peaking effect (freq. & amplitude of the peak) -- the input capacity could be calculated.
Like I would do that with a high Rf value, so as to obtain better visible noise floor changes and peaking at lower frequency.
This peaking effect, and the consequent stability criteria are the main reasons for which that Dac output C value could be interesting.
All this becomes less of an importance, if the adviseable Cfeedback parallel capacitance i the I/V circuit gets applied (integrating I/V converter) with a better defined pole
dunno this is why I ask, I read something here (I can't not find again the link sorry) that said output capacitance of a dac chip is important in the final capacitance the inverted input see with the addition of the layout (stray capacitrance + trace).
But maybe I mistake about the word ! Possibly...
Was curious after having read the Texas Instrument SLOA013A paper.
One way to minimise its importance is to lowish rF Z value, rigth ?
We have no obligation about the 2 V output like with cd players with ours DIY. Mosr pre + amp has much more gain than needed and often with pre works better with the pot towards 12h00 position...
In my Aya DAC for instance I work with only 1kR as I/V r. And 11h00 pot of my pre is already very loud.
Thanks!
What measurement setup is used for noise peaking in practice? The peak is likely in the MHz region, right? Are unity gain stable opamps also affected?
Interestingly, the same opamp topology is used in current input MC phono stages, yet never heard the issue discussed in that context. Easily 100p of wire capacitance but perhaps the very low source resistance negates the effect of capacitance.
yes, unity gain stable opamps are showing the same. For measuring, I shamefully use our scopes in spectrum analysis mode. (Tek, R&S , Lecroy)
Just for illustration, here it is a simulated response: opamp AD828, Rf=20k, load capacity at -In is 0pF, 100pF, 1000pF
