R-2R DAC Kit

diyiggy

Member
2019-01-16 12:22 am
This thread reminds me the same discussion between cars & electric cars. People want eventually technology, hype. But do they need it for a good drive or to reassure themselves ?


Well I advise the oldest cheap but sota layouted, complete kit from Audial / P. Rogic... if you have a tda1541A chip already. USB embeded, uf-l plug I2S input proof but Mostly you will don't care anymore...cause it sounds awsome & right ! Eventually better : a Total DAC with true precision concistency in resistors and sota layout around : pricey ! A good AD1862/PCM63 but better the AD (more neutral) pushed at its most like an AYA dac or an AMR dac did with the tda1541A : of course yes.



I hesitate to say Linn Sondek LP12 but it would have seen off topic, lol.


EDIT : what is around the digital conversion operation DOES matter : front-end, powersupply, clock, pcb layout experience, and so-on. You listen to the sum of that in a dac device. It is known but safe to be said again & again.
 
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diyiggy

Member
2019-01-16 12:22 am
It's not a kit but imho the best bet for Q/P & it's not a diy dac but at the end certainlt close when all is made : box, powersupply, etc is the R2R one of EC DEsigns : why ? The front-end is well managed, the guy has some talents, that a subjective trust but all the people that purchased one and had good dacs had testimonied into this direction . well slighty off topic as no diy but piggy back bad diy dac projects can cost more in few years than a good enough branded.
 
Your comment was about required resistor network accuracy and you didn't include a quoting text, but it is placed immediately after my message. Now your explanation makes it clear, but you can't blame the messenger.

My point was about the fact that calibration reduce requirements for resistor accuracy. It is why it is relevant to your (previously quoted) message. Whether it is a pure R2R (resistor) or I2I network (current source) network, it doesnt matter. my point is still valid, so I don't understand a reason of your arguing that TDAxxx is not R2R architectuire. This is also a ladder architecture and works on the same principle, so calibration makes sense.

Once the above is clear. It is advertised that Audio GD DA-8 modules do self calibrating. I am interested how it could be done.

sajunky, as I told you before, that's simply not possible, those modules don't have hardware for doing any calibration, that PLD is way too tiny....
 
Yeah, you told us already, but I don't believe, as you are being unfair to the competitors. No one is better than you, so you would have to give us a proof.

On my side I found it can be true. When exposed to the extensive ground loops device fails calibration. Sound do not improve at all, even during warming up. ASR has detected in this situation a pulse every 20 second. After removing a cause sound improves immediately after switching on and continue improving during the first 30 minutes. This is my personal experience.
 
I'm not unfair to anybody, any competent engineer can tell you that a tiny PLD don't have the logic resources to do any kind of calibration by itself, and I don't see an ADC on the DA-8.... I can't deliver proof of a negative, but please, do provide proof that the DA-8 module can calibrate itself or stop claiming it can....

But when the DA-8 module is used in a system, that system can have a more powerful processor and/or FPGA and the ADC needed to do calibration....
 
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have you seen or tried DAC8811? :D it is the version with current output, glitch seems be small, but the sound still be unknown

No, I've not seen that one before, very cute package. 2nV-S glitch is small for you? For me that's rather large I prefer those in single digit pV-S. Lack of dynamic characterization is something of a turn-off for me in audio applications - notice the THD number is given in multiplying mode with a fixed digital input as with AD5547.
 
I am excited to see when someone tries the DAC11001A! Though it can be a bit intimidating.
It has a pretty aggressive track-and-hold which brings in the glitch quite a bit. It should also be noted that for R-2R DACs the glitch is code dependent. Even though the DAC11001A does not bring the glitch to single digit pV-s range, it is approximately the same for all codes.
 

miro1360

Member
2010-03-20 3:20 pm
I bought DAC702BH chips from ebay, not tried it yet :D
Nice chip design.
 

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