Okay, thanks.
I see a number of problems. Power supply wires are much longer than necessary. Regulators should be closer to the dac board and wiring from power supplies to dac board should be as short as possible.
The dual buffered LT1042 voltage regulator boards share one ground between both channels. It means there are ground loops with big loop areas due to the way the wiring is laid out. Also those regulators, as implemented by the Chinese designer/manufacturer, don't sound very good IME. I do use them as pre-regulators, but not as final regulators.
The USB board should be run on clean +5v power, not USB power. Can't tell if you are using a modified USB cable for that purpose?
The I2S wiring between the dac board and the USB board is longer than necessary and is wired improperly. There should be one dedicated ground for each of the three I2S signals, not just one shared ground for all the signals. Each signal wire and its dedicated ground should be lightly twisted together, and each twisted pair should be a bit separated from the other twisted pairs. Use only gold pin headers and female pin connectors. IME tin connectors get more jittery after sitting a few hours, and are never the same again after that. Experiments show contact pressure diminishes with time, which seems to be one source of the jitter increase (maybe the primary cause with tin). Not a problem for non-critical signals, but IME it is a problem for jitter (that the ESS internal ASRC would then have to attenuate; better for there to be less jitter in the first place).
The dac board and USB board should be in a shielded steel case, not open air. They will pick up EMI/RFI from many sources common in today's homes.
It helps if the whole system including dac and power amp are powered from one high quality power conditioner with common-mode chokes to help reduce power cord ground loops and ground coupled noise from the AC line.
Once all the more obvious problems are fixed, then it would help to connect to the dac chip I2C bus with an Arduino or other MCU. Then set DPLL_Bandwidth as low as possible, as ESS recommends. Some people have said it helps SQ more than anything else they tried (not that many different things were tried in those cases).
I see a number of problems. Power supply wires are much longer than necessary. Regulators should be closer to the dac board and wiring from power supplies to dac board should be as short as possible.
The dual buffered LT1042 voltage regulator boards share one ground between both channels. It means there are ground loops with big loop areas due to the way the wiring is laid out. Also those regulators, as implemented by the Chinese designer/manufacturer, don't sound very good IME. I do use them as pre-regulators, but not as final regulators.
The USB board should be run on clean +5v power, not USB power. Can't tell if you are using a modified USB cable for that purpose?
The I2S wiring between the dac board and the USB board is longer than necessary and is wired improperly. There should be one dedicated ground for each of the three I2S signals, not just one shared ground for all the signals. Each signal wire and its dedicated ground should be lightly twisted together, and each twisted pair should be a bit separated from the other twisted pairs. Use only gold pin headers and female pin connectors. IME tin connectors get more jittery after sitting a few hours, and are never the same again after that. Experiments show contact pressure diminishes with time, which seems to be one source of the jitter increase (maybe the primary cause with tin). Not a problem for non-critical signals, but IME it is a problem for jitter (that the ESS internal ASRC would then have to attenuate; better for there to be less jitter in the first place).
The dac board and USB board should be in a shielded steel case, not open air. They will pick up EMI/RFI from many sources common in today's homes.
It helps if the whole system including dac and power amp are powered from one high quality power conditioner with common-mode chokes to help reduce power cord ground loops and ground coupled noise from the AC line.
Once all the more obvious problems are fixed, then it would help to connect to the dac chip I2C bus with an Arduino or other MCU. Then set DPLL_Bandwidth as low as possible, as ESS recommends. Some people have said it helps SQ more than anything else they tried (not that many different things were tried in those cases).
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ESS chips work fine. But that board is garbage. 2 layer, no decoupling. I advise cutting your losses.
Hi svadim79,
System looks more or less of average performance. From that I would guess there will be a limit as to how good a dac would be an appropriate match for the rest of the system.
IMHO, I agree with InspectorGadget that diyinhk dac board is not ideal for your intended use. There are just too many problems that can't be fixed with it. Two layer dac boards will never be very good. Even back in the days of 16-bit dacs it was recommended to use at least 4-layer PCBs. That doesn't insure quality design of course, but it least it makes quality design possible.
In addition, the best sounding ESS dacs I have heard use synchronous mode operation which requires two clocks and some means to switch between them (more like what is used for AKM dacs). It also requires I2C control of dac registers. IMHO there is more that could be said, but the above is a start on what would be needed.
EDIT: IMHO and IME, what the ESS dac board you have now is good for is mostly for experimenting with and for learning how to program I2C registers, not much more than that.
System looks more or less of average performance. From that I would guess there will be a limit as to how good a dac would be an appropriate match for the rest of the system.
IMHO, I agree with InspectorGadget that diyinhk dac board is not ideal for your intended use. There are just too many problems that can't be fixed with it. Two layer dac boards will never be very good. Even back in the days of 16-bit dacs it was recommended to use at least 4-layer PCBs. That doesn't insure quality design of course, but it least it makes quality design possible.
In addition, the best sounding ESS dacs I have heard use synchronous mode operation which requires two clocks and some means to switch between them (more like what is used for AKM dacs). It also requires I2C control of dac registers. IMHO there is more that could be said, but the above is a start on what would be needed.
EDIT: IMHO and IME, what the ESS dac board you have now is good for is mostly for experimenting with and for learning how to program I2C registers, not much more than that.
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"You want to say that oppo udp 205 (es9038pro) is also not good sounding device???"
Yes! IMHO, Oppo knew they had a problem. They consulted with a well known high end designer to see if he had any fixes to try. IIUC he did, but the Oppo chief engineer didn't want to use any of them. Again IIUC, cost was a big issue for them; they didn't want do anything that would increase manufacturing cost.
The preceding is my personal opinion only, nothing more.
Yes! IMHO, Oppo knew they had a problem. They consulted with a well known high end designer to see if he had any fixes to try. IIUC he did, but the Oppo chief engineer didn't want to use any of them. Again IIUC, cost was a big issue for them; they didn't want do anything that would increase manufacturing cost.
The preceding is my personal opinion only, nothing more.
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