I never liked TPS7A4700 on dac analog supply, if...i always put choke between last 2..3 small filter caps. Sometiomes helped sometimes not. Souns was to sharp, thin, empty, colourless... Also on opamp power lines was not ok, even as preregulator on soekris dac. But i like them on digital lines.
Details, cleanines, "transparency" ...this is far away from real music that touch your emotions...
Details, cleanines, "transparency" ...this is far away from real music that touch your emotions...
Right, which is why I referred to LDOs as having common-emitter outputs
Yep - but I've never met a series reg with a lower output impedance at lower currents. Shunts may well have such a characteristic but not series regs.
Right, which is why I referred to LDOs as having common-emitter outputs
Yeah, not reading the post again, DOH
haha Or does the OP Z even matter beyond 10m ohms or so?
A short length of wire or PCB track is that.
T
I've taken to running opamp power rails from solid groundplanes surrounded by caps to get the impedance seen at the power pins below 10mohm at higher frequencies. Not sure how much the leadframe and bond wires contribute though.
A useful rule of thumb I recently discovered - for 1oz copper the resistance is about 0.5mohm per square. So to get 10mohm you'd need a 20mm long 1mm wide track for example.
A useful rule of thumb I recently discovered - for 1oz copper the resistance is about 0.5mohm per square. So to get 10mohm you'd need a 20mm long 1mm wide track for example.
It can seem that way until a dac is as flawless as it can be. One can play around modifying distortion more to one's musical taste, but it always sounds like it is distortion tuned to taste.
IME, the reason details, cleanliness, and transparency may seem undesirable is because getting to that point then exposes other lower level distortion problems that need fixing too.
It is very complicated to get a Sabre dac highly optimized, lot's of details. No wonder people keep looking for answers in R2R dacs and other older topologies.
Let's hope AK4499 will make it less complicated to make a really good sounding SD dac with very low distortion.
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In case there is any interest here for ES9038Q2M project use, I have been reporting on some subjective tests done on dac I am trying to get a point wherein I like it enough to use for some further tests in relation to what I have been working on in this thread with AK4137. A summary of how the other dac is coming along so far can be found at: https://www.diyaudio.com/forums/pc-...essions-tweaks-mods-hints-39.html#post5802312
Things are starting to look a little more complicated with that other dac I have been working on. It is designed to use one AVCC supply for both left and right channels, an unfortunate decision it appears. Also, as various sources of distortion are found and reduced, and as the boards are operated in a physically more separated layout from each other which reduces stray coupling between them, sound quality has gotten good enough to hear that some remaining issues may not be practical to remedy. Too bad. I was hoping to avoid modding another Chinese ES9038Q2M board from scratch. It may be that I will have to do something like that when I feel up to starting in on it. Lots of work, as some of you know first hand. Could be in the meantime I will do what I can with the other dac I have at the moment, but then switch to AK4499 at some point when it becomes available. I can still compare different power supplies in the meantime, for example. Just don't think I will get to the level of sound quality I was hoping for with the other dac I am now working on now, which may eventually limit what level of development I can use it for.
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Mark,
as a much less expensive alternative for PCM to DSD upsampling I would consider Audirvana.
Some say it is on par with HQPlayer and much better than AK4137.
Matt
Matt,
I looked at Adurivana website some. Looks like it uses SOX and VST3 plugins to do whatever one wants that those resources can do. Not sure if there is anything more or less equivalent to what HQplayer can do built into SOX. Maybe there is. Haven't looked at it for a very long time. Pretty sure there are no DSD modulator VST3 plugins.
-Mark
I looked at Adurivana website some. Looks like it uses SOX and VST3 plugins to do whatever one wants that those resources can do. Not sure if there is anything more or less equivalent to what HQplayer can do built into SOX. Maybe there is. Haven't looked at it for a very long time. Pretty sure there are no DSD modulator VST3 plugins.
-Mark
Some interesting info about a new ES9038Q2M dac, and and new USB/RPi type of board that could potentially do DSD2048. Starts at: https://www.diyaudio.com/forums/ven...nti-dual-lps-5v-3a-5v-1-5a-6.html#post5806394
Hopefully, at least one of the dac boards will be here before too long for review...
Hopefully, at least one of the dac boards will be here before too long for review...
It's been a little while since I last asked, so maybe we can catch up with where folks are at to see if any recent progress. Is anyone getting close to trying to access dac registers over I2C bus? If so, I am ready and willing to help out as much as I can.
In the meantime, I have been posting now and then about the 9038Q2M dac I am working on over in the other thread to hopefully get it to where I can use it as a substitute test dac for some new clock division experiments. If that one doesn't work out, have another candidate in mind.
In the meantime, I have been posting now and then about the 9038Q2M dac I am working on over in the other thread to hopefully get it to where I can use it as a substitute test dac for some new clock division experiments. If that one doesn't work out, have another candidate in mind.
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It's been a little while since I last asked, so maybe we can catch up with where folks are at to see if any recent progress. Is anyone getting close to trying to access dac registers over I2C bus? If so, I am ready and willing to help out as much as I can.
In the meantime, I have been posting now and then about the 9038Q2M dac I am working on over in the other thread to hopefully get it to where I can use it as a substitute test dac for some new clock division experiments. If that one doesn't work out, have another candidate in mind.
Hello. I'm ready. My board ardyino will come soon. Please, tell me how I will do this?
@888777,
It depends in part which model Arduino you are getting. In any case you need to install the Arduino software on a computer. I recommend using the portable option: Arduino - PortableIDE
Hook it up and run a few of the example programs so you start to get the idea of how to use it. Please ask if any problems doing that.
You also have do decide where you want to connect the I2C lines to the dac board you have. Where and how that is done depends on which board and firmware version you have. If questions about your specific dac board, please ask.
To find out which pins on your particular model Arduino are used for I2C bus, try googling for the pinout diagram for that model. A good pinout diagram will show both SDA and SCL which are the I2C pins.
Then, it is a good idea to hook up the Arduino to the dac such that if either the Arduino or dac is powered on when the other one is off, no electrical damage can occur to the one that is powered off. One approach for that is the Sparkfun board described in the first post below, it is good for 5v Arduinos (please ask if your Arduino is a 3.3v model).
Some info in previous posts:
https://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-442.html#post5781420
https://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-437.html#post5777854
https://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-442.html#post5781315
If additional questions I haven't addressed so far, then please ask about specific questions.
It depends in part which model Arduino you are getting. In any case you need to install the Arduino software on a computer. I recommend using the portable option: Arduino - PortableIDE
Hook it up and run a few of the example programs so you start to get the idea of how to use it. Please ask if any problems doing that.
You also have do decide where you want to connect the I2C lines to the dac board you have. Where and how that is done depends on which board and firmware version you have. If questions about your specific dac board, please ask.
To find out which pins on your particular model Arduino are used for I2C bus, try googling for the pinout diagram for that model. A good pinout diagram will show both SDA and SCL which are the I2C pins.
Then, it is a good idea to hook up the Arduino to the dac such that if either the Arduino or dac is powered on when the other one is off, no electrical damage can occur to the one that is powered off. One approach for that is the Sparkfun board described in the first post below, it is good for 5v Arduinos (please ask if your Arduino is a 3.3v model).
Some info in previous posts:
https://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-442.html#post5781420
https://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-437.html#post5777854
https://www.diyaudio.com/forums/digital-line-level/314935-es9038q2m-board-442.html#post5781315
If additional questions I haven't addressed so far, then please ask about specific questions.
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Looks like I'm back home here. Have to find a different dac for doing some experiments to simply getting the best sound out of ES9038Q2M and AK4137 at low cost. The one I had hoped would work had a flawed AVCC implementation (at least for my purposes), one that wasn't worth trying to fix with mods.
Now in the midst of trying to get another Sabre dac up and running that will hopefully work as a suitable test bed for some things I want to try. This time it happens to be an ES9028PRO, but the intention is that any results should apply equally well for further development of the ES9038Q2M project.
Now in the midst of trying to get another Sabre dac up and running that will hopefully work as a suitable test bed for some things I want to try. This time it happens to be an ES9028PRO, but the intention is that any results should apply equally well for further development of the ES9038Q2M project.
An Arduino program that can read and write I2C bus registers can be found at: Dropbox
You may need to edit which pins and port are for I2C given the model of Arduino you have. You might also need edit the I2C address of the device you want to communicate with. Right now the I2C address for the dac boards we use in this thread and for AK4137 are in the program. You will also need to download any included libraries the program calls out if you don't already have them. The Arduino software can import libraries in zip format that you download, no need to unzip them.
Probably the first thing to try would be to see how far you can reduce PCM and DSD DPLL settings without losing playback stability. It's good to try to familiarize yourself with the other register options.
Another very useful thing to do is adjust H2 and H3 harmonic distortion compensation, then enable them. There are registers for all of that. For proper adjustment you would need a sound card with a line input and a notch filter. We can talk about the particulars when you are ready. No point in overloading people with too much at once. For people new to Arduino, there can be a learning curve for that.
So far as I know, any Arduino could work. If you check the pinout diagram for a particular Arduino you can see if there are pins labeled SDA and SCL (the I2C signal pins). I assume there are always some pins set aside as preferred for that use.
The main thing about Arduinos is that most run on 5 volts. That means they should work well with the Sparkfun level translator which would be recommended to protect the devices for damaging each other in the event one device is powered off while the other device is still powered on. The only exceptions to that are the few 3.3v Arduino models. The Sparkfun device I linked to requires that one device be at a higher voltage than the other. Since the dac runs on 3.3v and Arduino usually runs on 5v, the voltage differential requirement is satisfied. For anyone with a 3.3v Arduino, we could talk about how to interface it to the dac while maintaining protection for both devices.