Well, the SMPS it have a main advantage: is very energy efficient. Then it not dissipate heat, and is quite cheap to produce it.
The linear PSU it lose a important part of its energy effectiveness by dissipating it in heat. Exhausting the heat it may be a challenge in some particular cases. Also the transformer is an enough heavy/big, and quite costly part of such linear device...
However, when to compare it functional on a targeted device, the linear power it come far better, regarding the impact over the final result. Also some reasonable appreciations have to be made it, when deciding the use of a linear PSU instead of a SMPS one. The overall power the targeted device may need it. There is not so rational to use a linear PSU to power a whole computer, which it may need hundreds of watts... Here a SMPS is far more rational to use it. In my opinion, a SMPS is not a PSU which is just the right one to use it in a hifi audio device...
There is another aspect when to use a SMPS for a digital stage: its large spectre noises become mixed in a enough complex way with the HF noises issued by the digital activity itself. A SMPS it will always increase the overall noise level into a system. In opposition, a linear PSU (which it not generate HF noises at all), it contribute to lowering the overall noise level into the same digital system.
However, everybody can make some simple measurements (a scope may be needed) to see/experience himself the noise differences, as the positive impact of using a linear power for a targeted digital system.
The linear PSU it lose a important part of its energy effectiveness by dissipating it in heat. Exhausting the heat it may be a challenge in some particular cases. Also the transformer is an enough heavy/big, and quite costly part of such linear device...
However, when to compare it functional on a targeted device, the linear power it come far better, regarding the impact over the final result. Also some reasonable appreciations have to be made it, when deciding the use of a linear PSU instead of a SMPS one. The overall power the targeted device may need it. There is not so rational to use a linear PSU to power a whole computer, which it may need hundreds of watts... Here a SMPS is far more rational to use it. In my opinion, a SMPS is not a PSU which is just the right one to use it in a hifi audio device...
There is another aspect when to use a SMPS for a digital stage: its large spectre noises become mixed in a enough complex way with the HF noises issued by the digital activity itself. A SMPS it will always increase the overall noise level into a system. In opposition, a linear PSU (which it not generate HF noises at all), it contribute to lowering the overall noise level into the same digital system.
However, everybody can make some simple measurements (a scope may be needed) to see/experience himself the noise differences, as the positive impact of using a linear power for a targeted digital system.
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Switching supplies are fairly expensive to engineer, this is why you'll find off-the-shelf commercial switchers in audio products. They're going to compromise audio performance because they're not really fit for purpose.
Linear PSUs do generate HF noise - have you not read about audiophiles swapping out rectifier diodes in their supplies? The ones that are generally favoured are 'soft-recovery' or Schottkies.
Linear PSUs do generate HF noise - have you not read about audiophiles swapping out rectifier diodes in their supplies? The ones that are generally favoured are 'soft-recovery' or Schottkies.
Linear PSU it generate indeed an amount of HF, if one should go deep into details and analyse it as an electronic device. At least every electronic device it generate more or less HF noises. The point here is that the differences in HF generated noises, between an SMPS versus a linear PSU, it are enormous. While a good "silent" SMPS noise level is in teens mV range, the linear PSU it is in µV - nV range. While a SMPS noise spectre is very large for quite high levels, the linear PSU noise spectre is very limited with levels bearable measurable...
Very important is to remember in this discussion (quite OT for this thread), that there is not about powering a analogue stage with a SMPS or linear PSU, but a digital stage. A digital stage is noisy by its nature (much more noisy than the noises generated by a linear PSU). Using a SMPS to power a such digital stage it increase the overall noise level into the system. Powering the same stage from a linear PSU it lower the overall noise level in the processing system.
After this enough extended PSU discussion, I may suggest we go back to the real topic of this thread: Oppo Sonica DAC...
Very important is to remember in this discussion (quite OT for this thread), that there is not about powering a analogue stage with a SMPS or linear PSU, but a digital stage. A digital stage is noisy by its nature (much more noisy than the noises generated by a linear PSU). Using a SMPS to power a such digital stage it increase the overall noise level into the system. Powering the same stage from a linear PSU it lower the overall noise level in the processing system.
After this enough extended PSU discussion, I may suggest we go back to the real topic of this thread: Oppo Sonica DAC...
HA-2 forthcoming?
The Oppo HA-1 has its fans.
The great news is that the ES9028pro DAC chip is pin compatible with the ES9018, by design. Makers can use the new, much improved 9028pro with a minimum of effort. Updated firmware to allow selection of pre-programmed filters and other new features is a much smaller effort than a board re-design. Chinese makers like Gustard made the upgrade months ago, and hopefully Oppo can too in 2017.
The Oppo HA-1 has its fans.
The great news is that the ES9028pro DAC chip is pin compatible with the ES9018, by design. Makers can use the new, much improved 9028pro with a minimum of effort. Updated firmware to allow selection of pre-programmed filters and other new features is a much smaller effort than a board re-design. Chinese makers like Gustard made the upgrade months ago, and hopefully Oppo can too in 2017.
Naked photos of the Oppo Sonica DAC
You've seen the internal photo posted by Oppo. The shipping product has one notable difference: a strange ceramic block atop the ES9038pro dac chip. Also visible are the output traces from the dac to the I/V and output buffers. The balanced sections are on the outside and single-ended in the middle.
Op amps are LM4562 and LME49724. Voltage regulators include LM2940 and 7912 for +/- 12v, 7805 for logic, mp2019, az1117. PCM1808 ADC. 2x df02S rectifier bridges. The third photo shows the Xmos USB receiver.
Full sized images not reduced by diyaudio here: https://drive.google.com/open?id=0B8n6TAaE9yPJVU1JSTNIT1FqbkE
You've seen the internal photo posted by Oppo. The shipping product has one notable difference: a strange ceramic block atop the ES9038pro dac chip. Also visible are the output traces from the dac to the I/V and output buffers. The balanced sections are on the outside and single-ended in the middle.
Op amps are LM4562 and LME49724. Voltage regulators include LM2940 and 7912 for +/- 12v, 7805 for logic, mp2019, az1117. PCM1808 ADC. 2x df02S rectifier bridges. The third photo shows the Xmos USB receiver.
Full sized images not reduced by diyaudio here: https://drive.google.com/open?id=0B8n6TAaE9yPJVU1JSTNIT1FqbkE
Attachments
Much appreciated your contribution, with these detailed inside pictures here.
Old approach/design adapted to a new product. Minimal design improvements for the DAC section, as I can see into these pictures, compared with Oppo previous products..
Indeed, what a hack is that on the DAC chip top? It looks to me as a passive device.
Has Oppo adopted in the last time a mystical way of electronic design? A kind of "bybee" device on top of the DAC chip to improve its performances? I should expect a heatsink on the top of the DAC, as a more logical approach, but this ceramic (or whatever material may be) device is very strange indeed...
A DAC chip capable for -140dB dynamics, used into this Sonica, specified for -120dB dynamics, with a mystical ceramic device on its top for improved performances?
This it looks to me quite astonishing as design concept... If this mysterious device is glued well on that chip, it may be a big problem for further (my) modifications in this area...
At least this kind of DAC heat it is hide now the marking on that chip... It is used a 9028Pro instead of 9038Pro, and this it is hidden by using this trick with a such ceramic cover...
I assume Oppo should explain soon what about this "unexplained" and unexpected design "invention"...
Old approach/design adapted to a new product. Minimal design improvements for the DAC section, as I can see into these pictures, compared with Oppo previous products..
Indeed, what a hack is that on the DAC chip top? It looks to me as a passive device.
Has Oppo adopted in the last time a mystical way of electronic design? A kind of "bybee" device on top of the DAC chip to improve its performances? I should expect a heatsink on the top of the DAC, as a more logical approach, but this ceramic (or whatever material may be) device is very strange indeed...
A DAC chip capable for -140dB dynamics, used into this Sonica, specified for -120dB dynamics, with a mystical ceramic device on its top for improved performances?
This it looks to me quite astonishing as design concept... If this mysterious device is glued well on that chip, it may be a big problem for further (my) modifications in this area...
At least this kind of DAC heat it is hide now the marking on that chip... It is used a 9028Pro instead of 9038Pro, and this it is hidden by using this trick with a such ceramic cover...
I assume Oppo should explain soon what about this "unexplained" and unexpected design "invention"...
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I'll surely buy a Sonica DAC in the near future but so far I hadn't read any reviews of how amazing this dac sounds out the box, perhaps it isn't that good after all.
The other thing holding me up it's that white cap over the chip, it's like an attemp to keep a dirty secret under the hood. It looks like it's simply crimped to the pcb and it wouldn't be so hard to remove.
I recently contacted oppo, they don't seem very interested in selling this thing worldwide, only north america.
The other thing holding me up it's that white cap over the chip, it's like an attemp to keep a dirty secret under the hood. It looks like it's simply crimped to the pcb and it wouldn't be so hard to remove.
I recently contacted oppo, they don't seem very interested in selling this thing worldwide, only north america.
I think it may be very special if Sonica DAC it will sell it only in North America. I have informations that this DAC it may come soon to Europe too... A very limited number of devices it was already sold in Europe... Let`see...
Indeed it is a little bit strange that this product it was not yet reviewed.
Else it seems to be the only consumer DAC (for a reasonable price), which it have inside the newest ESS Sabre chip.t
It have to sounds very particular, as it have that ceramic hat over the DAC chip... Nobody did like this until Oppo came on this revolutionary idea... I can bet that we will see soon on Ebay such white briks for sale for the ones who may want to improve the sound of their (ESS Sabre based) DACs...
It could be ESS themselves which recommended a such device glued on the chip, for some mystical reasons or improvements?
Indeed it is a little bit strange that this product it was not yet reviewed.
Else it seems to be the only consumer DAC (for a reasonable price), which it have inside the newest ESS Sabre chip.t
It have to sounds very particular, as it have that ceramic hat over the DAC chip...
Nobody did like this until Oppo came on this revolutionary idea... I can bet that we will see soon on Ebay such white briks for sale for the ones who may want to improve the sound of their (ESS Sabre based) DACs...It could be ESS themselves which recommended a such device glued on the chip, for some mystical reasons or improvements?
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Indeed. He got it already from US market, or is the one of the very few which it was exported to Europe...
My (ready) mods for this device it will come later, as I haven`t access yet to this product, and I can not buy it in Europe... Not happy at all about, but so it is...
I hope it will be later sold on European market too...
My (ready) mods for this device it will come later, as I haven`t access yet to this product, and I can not buy it in Europe... Not happy at all about, but so it is...
I hope it will be later sold on European market too...
Maybe there's a 9038Pro under that white hat after all , I'm impatientely waiting for someone to remove it and take pictures!!!. Perhaps it's totally fused with the PCB and it requires semi destroying the board to lift it. Does anybody want to waste $800 plus s&h just to let us know, I hope so!
, I'm impatientely waiting for someone to remove it and take pictures!!!. Perhaps it's totally fused with the PCB and it requires semi destroying the board to lift it. Does anybody want to waste $800 plus s&h just to let us know, I hope so!
It looks like this is now the talking point of this thread: the hat on DAC...
Indeed, this is quite an subject: what is all about that DAC hat?
I presume it may not be so dramatic at that piece of what it may be, it is glued so hard on the chip. For sure it is glued on the chip, and not on the PCB. Maybe the chip it could be glued on PCB, but this is something else...
Before removing it, I think it may be more useful to find out what it may be the role of that thing on the top of the DAC.
What for Oppo designers chosen to design a such object (same dimensions as the chip), and then using it to cover the chip?
I`m in fact more impatiently to find out how it sounds this DAC with and without that hat on it...
Indeed, this is quite an subject: what is all about that DAC hat?
I presume it may not be so dramatic at that piece of what it may be, it is glued so hard on the chip. For sure it is glued on the chip, and not on the PCB. Maybe the chip it could be glued on PCB, but this is something else...
Before removing it, I think it may be more useful to find out what it may be the role of that thing on the top of the DAC.
What for Oppo designers chosen to design a such object (same dimensions as the chip), and then using it to cover the chip?
I`m in fact more impatiently to find out how it sounds this DAC with and without that hat on it...
May be that piece of ceramic was actually added by the owner who taken the photos? The drawbacks opinions of SMPS are mostly exaggerated by audiophiles and even Soulution has switch to SMPS in their latest high-end stuffs. Check out Archimago's Musings tests on these.
Archimago's Musings: MEASUREMENTS: ODROID-C2 with Volumio 2, and USB digital music streaming.
(Part III)
Oppo is a big company and the possibility of them using other chip than the advertised ES9038Pro is almost not existence. Oppo's design reminds me of some high-end Japanese stuffs that cost thousands.
Archimago's Musings: MEASUREMENTS: ODROID-C2 with Volumio 2, and USB digital music streaming.
(Part III)
Oppo is a big company and the possibility of them using other chip than the advertised ES9038Pro is almost not existence. Oppo's design reminds me of some high-end Japanese stuffs that cost thousands.
Regarding SMPS, and the using of such powering alternative for audio systems/devices, one should take a more nuanced look at this concept.
We can not compare a expensive/sophisticated SMPS power supply used into a high end high power amplifier, and this one used in Oppo very low power devices.
For your information, the new Oppo digital board used in the 20x series it use less than 1A (12v)...
When high power is needed by a system, then the SMPS is the best solution. Else, a SMPS it can be designed so to deliver enough clean power, but this it increase a lot its costs. A SMPS it can output a very low HF noise, if it get added linear regulation on its outputs. This design it increase the overall price of the SMPS itself and of the powered so device.
A SMPS is a definitive solution for a power hungry device. In a such device some noise sensitive stages it can be managed quite well in many ways, and with very good results.
All these above statements, do not fit at all for Oppo products. Here are used the cheapest SMPS one could design (lowering the production costs being a important target).
Oppo use SMPS in devices which it need very low power (40w or lower). In such devices it fit very well a linear PSU, knowing that a linear PSU is definitely superior when about HF noises and EMI emissions. In a low power device is not justified at all the use of a SMPS, knowing that the efforts to filter out the noises in the targeted device are quite important, it may increase the costs of the design and firmware, and it will have however negative impact over the overall quality of the final signals.
A linear PSU is far superior over a SMPS when about the quality of the power outputted.
A SMPS is far superior over a linear PSU when about energetic efficiency, and is to be used on high power devices, where the HF noises may have minimum impact over the final outputted signals quality. Or important efforts may be done to minimise/filter the HF noises, on costs expenses.
Powering a digital stage by a linear PSU it have a far superior impact over the final resulted signals, than when using a HF noisy SMPS. This approach is only limited by the power amount needed by that targeted digital stage. It is obvious a nonsense to use a linear PSU for a hundreds watts hungry digital system...
When we see that Oppo used a SMPS to power the digital stage of Sonica DAC, which may need something in between 20-30w, we can easily agree that this is definitively a wrong concept. Especially when about a expected high end audio device...
We can not compare a expensive/sophisticated SMPS power supply used into a high end high power amplifier, and this one used in Oppo very low power devices.
For your information, the new Oppo digital board used in the 20x series it use less than 1A (12v)...
When high power is needed by a system, then the SMPS is the best solution. Else, a SMPS it can be designed so to deliver enough clean power, but this it increase a lot its costs. A SMPS it can output a very low HF noise, if it get added linear regulation on its outputs. This design it increase the overall price of the SMPS itself and of the powered so device.
A SMPS is a definitive solution for a power hungry device. In a such device some noise sensitive stages it can be managed quite well in many ways, and with very good results.
All these above statements, do not fit at all for Oppo products. Here are used the cheapest SMPS one could design (lowering the production costs being a important target).
Oppo use SMPS in devices which it need very low power (40w or lower). In such devices it fit very well a linear PSU, knowing that a linear PSU is definitely superior when about HF noises and EMI emissions. In a low power device is not justified at all the use of a SMPS, knowing that the efforts to filter out the noises in the targeted device are quite important, it may increase the costs of the design and firmware, and it will have however negative impact over the overall quality of the final signals.
A linear PSU is far superior over a SMPS when about the quality of the power outputted.
A SMPS is far superior over a linear PSU when about energetic efficiency, and is to be used on high power devices, where the HF noises may have minimum impact over the final outputted signals quality. Or important efforts may be done to minimise/filter the HF noises, on costs expenses.
Powering a digital stage by a linear PSU it have a far superior impact over the final resulted signals, than when using a HF noisy SMPS. This approach is only limited by the power amount needed by that targeted digital stage. It is obvious a nonsense to use a linear PSU for a hundreds watts hungry digital system...
When we see that Oppo used a SMPS to power the digital stage of Sonica DAC, which may need something in between 20-30w, we can easily agree that this is definitively a wrong concept. Especially when about a expected high end audio device...
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I once negotiated a contract with a company in St.Petersburg. They asked me for a better price on the contract - they asked me to "take out the hat". I asked, what did they mean and their negotiator told me the following:
"A company hires a new sales guy. He goes on a business trip and comes back with a new hat. He submits his expense claim. His boss calls him into his office and says 'Hey, you can't claim for a hat, that's a personal item you have to pay yourself, take it off the claim'. The sales guy protests but has no choice. On his second trip he buys another hat and submits his expense claim. His boss calls him into his office and says 'Hey, we talked about this, we don't pay for hats'. The sales guy says 'But I always buy a new hat when I go on a successful sales trip'. His boss says 'No'. The sales guy comes back from his 3rd trip and again his boss calls him into his office and says 'Hey, your expense claim has no hat, very good!'. The sales guys says "Oh, it's in there alright, but you'll never find it !"
So when you buy your Oppo, tell them you're not going to pay for the hat.
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Well, out of the anecdotal aspect on this "hat" subject, that piece of ceramic like thing over the DAC chip it intrigue me a lot... What kind of approach it is such?!
I never seen something like this. More reasonable approach is to have a heatsink over that chip, but not a rectangular piece of ceramic like object...
I never seen something like this. More reasonable approach is to have a heatsink over that chip, but not a rectangular piece of ceramic like object...
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assuming it is just ceramic there's not much reason for it to be there I can think of except to provide a means to better distribute heat flow out of the top of the package by putting something with high thermal conductivity in contact with it - and an insulator to avoid eddy current/parasitic interaction with the circuits underneath. Dennis Morecroft will explain further.
Mi assumption is that ESS have made that chip to work as a whatsoever chip, without additional tings or stones/jewelries around or in it. I doubt seriously about the role or functions og such passive objects on an electronic highly integrated processor.
Else we may diving into a mystical world of electronics, where everything is allowed and everything it have a explanation more or less surreal.
So, we may have two alternative here: either the ESS have recommended to Oppo designers a such "passive device", for unknown reasons, or there is a invention of the Oppo`s engineers.
Well it may be another alternative: there is a joke of a Oppo worker, who glued a such piece of ceramic exactly on the DAC chip of the device Markk02474 bought it, and opened it to take pictures...
Interesting to know if somebody else have seen the same into his device...
Else we may diving into a mystical world of electronics, where everything is allowed and everything it have a explanation more or less surreal.
So, we may have two alternative here: either the ESS have recommended to Oppo designers a such "passive device", for unknown reasons, or there is a invention of the Oppo`s engineers.
Well it may be another alternative: there is a joke of a Oppo worker, who glued a such piece of ceramic exactly on the DAC chip of the device Markk02474 bought it, and opened it to take pictures...
Interesting to know if somebody else have seen the same into his device...
Yeah, we definitely need more feedback from Markk02474 on this device, like many others I'm curious about the performance of the power supply and sound quality between balanced vs unbalanced outputs.
The biggest drawback for me is that it doesn't support gapless playback from network/usb, I wonder why Oppo had such a hard time implementing this, even the new UDP 203 only supports ape, wav, and flac and this DAC none!
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