twocents is right, use Amanero's FSCLK pin to connect to I2S_WS.
The intent of having three ground pins is so you can run each I2S wire as a signal+ground twisted pair. You don't have to do that, but I've seen it done before, so my intent was to make it possible if you wanted to.
Hope that helps!
You said it's not about the looks, but it looks pretty darn nice to me! If that's your unclean look, your clean work must be absolutely exquisite!
Either way, I'm glad you like the sound, that is the most important part! I can't tell you how rewarding it is to see others get value out of something I made.
Thank you for sharing!
My setup has changed slightly since the last photo (in the post above) and I would not know how good/bad (or noise free) it really is – I cannot measure it or compare it to something else. I am not so clued up on low noise, linear vs smps PSUs. I simply used what I had in hand, and yes, I use two JPS64 PSU boards which I got as a generous gift from member xrk971. In fact, I received so many generous gifts for this project, including the HAT DAC board from Matt Garman, the Raspberry Pi 2B and the TPS7A4701 LDO from fellow audio friends. The Low-Noise PSU boards can be ordered here:
GB for Simple Cap-Mx Regulated Low-Noise PSU
And one can play around with different regulators using this board.
The little booster board in the photo is actually a DC-DC step down converter I used initially for testing before the PSU boards were up and running. It serves no purpose here and I have since removed it. I now have the the two Low-Noise PSU boards, each one fed from its own smps as follows:
Samsung 14V 1.8A smps -> PSU board with a LT1085CT-5 regulator and larger 2A inductor -> Rpi (via the GPIO pins)
Netgear 19V 1A wallwart -> PSU board with a TPS7A4701 LDO regulator -> HAT DAC board
Using this setup with my PCA headamp it is absolutely quiet- no hint of any noise on full volume. This DAC sounds best with this Class A amp and headphones. Absolutely gorgeous.
With my ACA + Aksa Lender preamp this setup is also dead quiet, but with my TDA7297 amp + B1 buffer I have ground loop issues and lots of noise.
Because I use such a mixture of different kinds of smps supplies to power each component, I have found that ground loop issues (or noise) are a result of this mix, since some supplies have an earth connection and some don’t. I am seriously planning on building an AC Filter, more info here:
AC filterr DIY ESA SILK
and here:
Mains Filter - diyAudio
What I like about this setup is that you can implement a switch for each AC outlet to either enable or disable the earth connection. This makes it easy to play around with different combinations to eliminate ground loop issues. Once I have built and connected all my goodies one day – preamp, Class A amp, Class D amp, Headamp, Rpi, DAC, Bluetooth receiver and active crossover – I will have 8 different supplies! Where will I hide them? What will my wife say?
With regards to SQ between the Amanero and Rpi stack – I cannot really say. I used the Amanero initially just as a quick test to see if the DAC works before plugging it into the Rpi. First impressions last and this DAC really sounded fantastic the first time it worked with the Amanero. But there was some noise that I could not have lived with using the Amanero like that. I guess it also depends on the source used. I used my Android phone and the Amanero was not grounded either.
GB for Simple Cap-Mx Regulated Low-Noise PSU
And one can play around with different regulators using this board.
The little booster board in the photo is actually a DC-DC step down converter I used initially for testing before the PSU boards were up and running. It serves no purpose here and I have since removed it. I now have the the two Low-Noise PSU boards, each one fed from its own smps as follows:
Samsung 14V 1.8A smps -> PSU board with a LT1085CT-5 regulator and larger 2A inductor -> Rpi (via the GPIO pins)
Netgear 19V 1A wallwart -> PSU board with a TPS7A4701 LDO regulator -> HAT DAC board
Using this setup with my PCA headamp it is absolutely quiet- no hint of any noise on full volume. This DAC sounds best with this Class A amp and headphones. Absolutely gorgeous.
With my ACA + Aksa Lender preamp this setup is also dead quiet, but with my TDA7297 amp + B1 buffer I have ground loop issues and lots of noise.
Because I use such a mixture of different kinds of smps supplies to power each component, I have found that ground loop issues (or noise) are a result of this mix, since some supplies have an earth connection and some don’t. I am seriously planning on building an AC Filter, more info here:
AC filterr DIY ESA SILK
and here:
Mains Filter - diyAudio
What I like about this setup is that you can implement a switch for each AC outlet to either enable or disable the earth connection. This makes it easy to play around with different combinations to eliminate ground loop issues. Once I have built and connected all my goodies one day – preamp, Class A amp, Class D amp, Headamp, Rpi, DAC, Bluetooth receiver and active crossover – I will have 8 different supplies! Where will I hide them? What will my wife say?
With regards to SQ between the Amanero and Rpi stack – I cannot really say. I used the Amanero initially just as a quick test to see if the DAC works before plugging it into the Rpi. First impressions last and this DAC really sounded fantastic the first time it worked with the Amanero. But there was some noise that I could not have lived with using the Amanero like that. I guess it also depends on the source used. I used my Android phone and the Amanero was not grounded either.
Twocents,
Thanks for your report. Very cool that you have successfully repurposed those switching supplies for audio use using the LDO boards. No doubt you are getting quiet performance, as I have seen X's excellent noise measurements for that PSU board. I have had some fun listening to this DAC through my PCA headphone amp as well. The effortless dynamics from that combo is incredible.
I am trying to learn more about AC filtering as well. I tried a CLC filter on the mains in front of my DAC but didn't notice a change. I know I have read somebody recommend against ferrite chokes on AC wires for audio due to magnetic field interaction. I do have snap-on ferrites on my DC supply wires, and i think they might help a smidgen.
Thanks for your report. Very cool that you have successfully repurposed those switching supplies for audio use using the LDO boards. No doubt you are getting quiet performance, as I have seen X's excellent noise measurements for that PSU board. I have had some fun listening to this DAC through my PCA headphone amp as well. The effortless dynamics from that combo is incredible.
I am trying to learn more about AC filtering as well. I tried a CLC filter on the mains in front of my DAC but didn't notice a change. I know I have read somebody recommend against ferrite chokes on AC wires for audio due to magnetic field interaction. I do have snap-on ferrites on my DC supply wires, and i think they might help a smidgen.
Increased DAC output
I really really don’t like modding a working board – it’s frustrating, messy and risky. But I managed to successfully mod my HAT v1.6 board - replaced the 1.1k I/V resistors (R4, R9) with 3.32k MELFs, but first had to remove the 3 largest caps before I could reach the resistors. I needed a higher output from this DAC to match the other sources in my system. The extra headroom really works well in my system and this DAC sounds even better now! YMMV
I really really don’t like modding a working board – it’s frustrating, messy and risky. But I managed to successfully mod my HAT v1.6 board - replaced the 1.1k I/V resistors (R4, R9) with 3.32k MELFs, but first had to remove the 3 largest caps before I could reach the resistors. I needed a higher output from this DAC to match the other sources in my system. The extra headroom really works well in my system and this DAC sounds even better now! YMMV
Hey Matt, long time no see. Is the project still going on? No pressure, just curious
The project is kind of on "pause" for now. Earlier this year I decided to donate the majority of my precious little free time to an old hobby: guitar playing. I'm still doing a little diyAudio, although now my focus is on audio electronics for guitar. In particular, I've built several pedals from BYOC, and am working on building a tube amp, the Trinity Triwatt.
So all my stereo diyAudio projects are on hiatus for the most part. Though I periodically check in here, keeping an eye on threads like this and a few others that are particularly interesting to me. I skim over new threads every now and then as well. And of course I respond to private messages. I have no shortage of love for diyAudio, but I do have a shortage of time! Someday I hope to have more time to dive back in to these projects, but that might be a while.
To be clear, for projects like this that I started, I will try to help anyone that needs it. If you post and I don't reply in a few days, feel free to PM me!
hey these are pretty cool !
I was just about to ask about sound differences (if you remember) between your front v1.6 (is it the latest?) and the ebay Little Giant. I don't find the original 8x anymore at ebay (the one Malefoda started and led to the wiki of mods), so I think I'd finally go for one of these two. Please don't feel forced to, anyway
Ebay does have this one which is largely the same circuit but in a bigger box (and at a much higher price) : L1387DAC 8Xse 8Parallel TDA1387 HiFi DAC Decoder Fiber Coaxial OTG with Subcard | eBay
If you're looking for your next DAC and have patience to wait a few weeks my prototype multiple paralleled TDA1387 (72 chips in the current incarnation, subject to change) is sounding highly enjoyable. I'm planning to put it up on the lingDAC thread in stages as individual boards are ready to go.
If you're looking for your next DAC and have patience to wait a few weeks my prototype multiple paralleled TDA1387 (72 chips in the current incarnation, subject to change) is sounding highly enjoyable. I'm planning to put it up on the lingDAC thread in stages as individual boards are ready to go.
hey Richard, thank you! yeah that one looks promising but too big, too expensive (or, a bit over my top)
This is a long race, not in a hurry at all. Going to have a good read at the latest messages in lingDAC thread. It will surely sound (much) better than both Matt's and the Little Giant, tho I suspect maybe at the expense of being much more complex to understand/modify/fix in an eventual fuckup from my soldering? Thank you again as usual.
Yes to increased complexity - lots more parts to solder, all the DAC chips are potential points for solder shorts. Conceptually though fairly simple to understand - its using completely passive I/V and only has active buffer stages after the I/V resistors. So hopefully not a complete devil to modify and extend (if the need arises).
Hey Richard, I'd just overlooked this: completely passive I/V?
Just some months ago you were saying active is so much better
I was also following the other threads with mods, where you were talking about using AD844, AD811, AD815 or AD8067. I surely missed context somewhere, but where are you these days respect active vs passive and most importantly, how did you arrive to the conclusion?
Thank you
Just some months ago you were saying active is so much better
I was also following the other threads with mods, where you were talking about using AD844, AD811, AD815 or AD8067. I surely missed context somewhere, but where are you these days respect active vs passive and most importantly, how did you arrive to the conclusion?
Thank you
Indeed I was - strange world isn't it ?
That was a particular form of passive I/V - the simplest one with just a resistor on the output of the DAC. Active was better than that as it allowed the DAC to operate with a much lower voltage excursion on its output pins. Current-source DACs prefer as low an impedance as possible to ensure the lowest signal-dependent variation on the outputs. But the active stage turned out - like practically all active stages - to be rather PSU quality dependent. A step-up transformer doesn't have that weakness - its entirely passive but it does need plenty of current to drive it, hence the paralleled DAC approach.I'm very much convinced that subjectively, a transformer is the best solution I have so far tried, but only in conjunction with multiple paralleled DACs. Whether the advantage is down to the trafo or down to the paralleling is hard to say. Note I'm not saying its 'transformer I/V' as transformers can't perform that function. Its being used to step up the impedance level between the DAC output and the I/V resistor so it can be considered to be applying passive voltage gain. I have also tried running the transformer into an active I/V stage (an improved design over the lingDAC's one) and didn't notice any difference so for now I'm keeping it very simple with just the resistor.
If anyone's interested to ask further questions, here is the thread about the latest DAC design : Grossly parallel multibit DAC adventures
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Hi Matt,
I'm listening at your v1.2 and I must tell you this is absolutely awesome. My current setup is mediocre: powered by SMPS brick through the RPi, long RCA cable, bad micro hifi amp + speakers… Even with all these drawbacks, the sound coming out of this is really fantastic. I'm unable to describe it, not very versed in technical sound jargon (not even in my mother tongue, let alone english), but it sounds pretty good. I know it can be improved, but I thought you'd like to know. I will definitely buy the components and build the v1.6, since I think it'll give me more flexibility. Once I have both I will start mods to the one that sounds better.
Thank you so much for creating these.
Sergi
I'm listening at your v1.2 and I must tell you this is absolutely awesome. My current setup is mediocre: powered by SMPS brick through the RPi, long RCA cable, bad micro hifi amp + speakers… Even with all these drawbacks, the sound coming out of this is really fantastic. I'm unable to describe it, not very versed in technical sound jargon (not even in my mother tongue, let alone english), but it sounds pretty good. I know it can be improved, but I thought you'd like to know. I will definitely buy the components and build the v1.6, since I think it'll give me more flexibility. Once I have both I will start mods to the one that sounds better.
Thank you so much for creating these.
Sergi