Hi, Simonvan!
What is your definition of PCM?
A possible answer may depend on the definition.
Beside that, do you have a clear understanding on a delta-sigma( sigma-delta) modulation?
Bunpei
What is your definition of PCM?
A possible answer may depend on the definition.
Beside that, do you have a clear understanding on a delta-sigma( sigma-delta) modulation?
Bunpei
I'd like to show my own understanding here.
ES9018 incorporates a multi-level (65 levels) delta-sigma(sigma-delta) modulator.
In "White Paper" published by ESS, they use the term "six bit". However, I think it should not be interpreted as "PCM" because "PCM" does not refer delta-sigma modulated data and refers a binary format of 2's compliment in general. A DA module in ES9018 processes 65 level delta-sigma modulated data coded in "Unary" or "Thermometer" coded and DEMed.
In the case of PCM input, a usual PCM data is converted into 65 level delta-sigma modulated data.
In the case of DSD input, I imagine the original DSD data is also converted first into a certain form of internal multi-level representation and then the data is delta-sigma modulated into 65 levels as PCM is processed.
ES9018 incorporates a multi-level (65 levels) delta-sigma(sigma-delta) modulator.
In "White Paper" published by ESS, they use the term "six bit". However, I think it should not be interpreted as "PCM" because "PCM" does not refer delta-sigma modulated data and refers a binary format of 2's compliment in general. A DA module in ES9018 processes 65 level delta-sigma modulated data coded in "Unary" or "Thermometer" coded and DEMed.
In the case of PCM input, a usual PCM data is converted into 65 level delta-sigma modulated data.
In the case of DSD input, I imagine the original DSD data is also converted first into a certain form of internal multi-level representation and then the data is delta-sigma modulated into 65 levels as PCM is processed.
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Pls tell me about 2 register setting for stereo mode for SPDIF/SERIAL/DSD input.
To make to get stereo mode for SPDIF/SERIAL/DSD input, which 2 registers do I set. I guess 1 register is #14. If it is right, another?
To make to get stereo mode for SPDIF/SERIAL/DSD input, which 2 registers do I set. I guess 1 register is #14. If it is right, another?
An externally hosted image should be here but it was not working when we last tested it.
Please tell me about the IC4(6 pin smd), IC5's name on the Buffalo 3 SE input.
Analog output without AVCC power
I'm recently trying a various AVCC power supply systems for ES9018 of mono configuration.
In the process, I happened to forget to connect an AVCC power and turned digital 3.3V and 1.2V on! Alas, how so? A small sound came from my amplifier though the level is low. What internal mechanisms may make such phenomena?
In my configuration, 8 channel analog signal pins are tied and connected to a primary of line transformer. No voltage is given to those analog out pins at all.
I'm recently trying a various AVCC power supply systems for ES9018 of mono configuration.
In the process, I happened to forget to connect an AVCC power and turned digital 3.3V and 1.2V on! Alas, how so? A small sound came from my amplifier though the level is low. What internal mechanisms may make such phenomena?
In my configuration, 8 channel analog signal pins are tied and connected to a primary of line transformer. No voltage is given to those analog out pins at all.
maybe it worked in some kind of Class B way? where the signal itself supplied the analogue bias voltage enough to get some signal through?
Hi, qusp!
Thank you very much for your post. I'm sorry that I could not catch on your explanation as I can imagine no circuit diagram along with your explanation because of my limited knowledge.
You told a possible "N-channel (MOS) arrangement" in the analog output stage of the DAC. Does your guess of this time match well your previous speculation?
Bunpei
Thank you very much for your post. I'm sorry that I could not catch on your explanation as I can imagine no circuit diagram along with your explanation because of my limited knowledge.
You told a possible "N-channel (MOS) arrangement" in the analog output stage of the DAC. Does your guess of this time match well your previous speculation?
Bunpei
i'm just guessing, but then thats all we can do yes?
what I mean is, depending on the exact format or type of the fets (unknown), perhaps the missing analogue reference supply can be replaced by signal, so the swing of the signal itself (generated previous to the output stage) is enough to get something through, by turning the fets on with whatever signal voltage is over the gate threshold voltage and RDSon, but not with enough drive/bias to get full output. without AVCC the return will be compromised too, which would also contribute to the lack of output strength, but I can see how there could be something.
again i'm just guessing here but that is a mechanism that would allow it. distortion will be significantly higher and the waveforms incomplete, but it would be recognisable as music.
what I mean is, depending on the exact format or type of the fets (unknown), perhaps the missing analogue reference supply can be replaced by signal, so the swing of the signal itself (generated previous to the output stage) is enough to get something through, by turning the fets on with whatever signal voltage is over the gate threshold voltage and RDSon, but not with enough drive/bias to get full output. without AVCC the return will be compromised too, which would also contribute to the lack of output strength, but I can see how there could be something.
again i'm just guessing here but that is a mechanism that would allow it. distortion will be significantly higher and the waveforms incomplete, but it would be recognisable as music.
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DPLL is not likely to be disabled on ES9018-2M
When I read a press release of new ES9018-2M, I got such an impression that we could disable DPLL functionality on the chip by setting a new register appropriately.
Today, after I browsed its datasheet for the first time, I thought it would be impossible.
Does anyone interpret the datasheet descriptions in different manners?
When I read a press release of new ES9018-2M, I got such an impression that we could disable DPLL functionality on the chip by setting a new register appropriately.
Today, after I browsed its datasheet for the first time, I thought it would be impossible.
Does anyone interpret the datasheet descriptions in different manners?
High pitch whining sound from ESS9018/TPAIII
Hi All,
I encounter some issues with the following setup:
MiniDSP Mini-Sharc with the digital input module (MiniDIGI) ->
TPA Buffalo III in voltage out mode (loaded with a 1K resistor and a 3300pF Low-pass filter)
I get a high pitching noise on the oputput of the DAC, that is with or without the I2S lines from the Mini-Sharc connected or not With the I2S lines connected the noise is changing slightly and less stable though.
All DIP-switches are OFF (apparently new firmware) as per the datasheet recommandation, only the SP/DIF input is ON (i.e. set to bypass).
I have tried different supplies for the DAC board (simple 7508 regulator, LT1963 regulator) nothing wont change.
I'd nned some help troubleshooting the thing, I am slowly getting crazy...
Hi All,
I encounter some issues with the following setup:
MiniDSP Mini-Sharc with the digital input module (MiniDIGI) ->
TPA Buffalo III in voltage out mode (loaded with a 1K resistor and a 3300pF Low-pass filter)
I get a high pitching noise on the oputput of the DAC, that is with or without the I2S lines from the Mini-Sharc connected or not With the I2S lines connected the noise is changing slightly and less stable though.
All DIP-switches are OFF (apparently new firmware) as per the datasheet recommandation, only the SP/DIF input is ON (i.e. set to bypass).
I have tried different supplies for the DAC board (simple 7508 regulator, LT1963 regulator) nothing wont change.
I'd nned some help troubleshooting the thing, I am slowly getting crazy...
Hi coolnose,
Sorry to hear you seem to be having some problems with your setup.
The best thing to do would be to start a thread in our support forum, along with some pictures and more details if possible.
Twisted Pear Audio Support
Thanks!
Russ
Sorry to hear you seem to be having some problems with your setup.
The best thing to do would be to start a thread in our support forum, along with some pictures and more details if possible.
Twisted Pear Audio Support
Thanks!
Russ
Try this fix : Sawtooth ripple on AVCC module - Buffalo DAC - Twisted Pear Audio Support
It worked for me.
It worked for me.
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Problem solved!
Actually nothing wrong with our implementation, just ripple on the AVCC as described by many users (including the solution) here:
Sawtooth-ripple-on-AVCC-module
We have done a quick and dirty job with short trimmed through hole ceramics (100pF) on top of the PCB - result: working like a charm and dead silent!
OPA 2209 and OPA2211 are on their way and will probably replace the LMP next week!
Big thanks to DIYAudio-member Zaireeka for pointing us straight to the solution!
Glad I could help!
I also ordered an OPA 2209 to replace the LMP7732 and remove the "hovering" 120pF caps... 😀
Bonnes écoutes ! 🙂
I also ordered an OPA 2209 to replace the LMP7732 and remove the "hovering" 120pF caps... 😀
Bonnes écoutes ! 🙂
Indeed! Thanks for the help!
It should be noted that was the older AVCC module, the current AVCC modules have a much less finicky op-amp and better compensation (phase margin) in the circuit.
I regret I did not notice right away that you had the old AVCC module.
It should be noted that was the older AVCC module, the current AVCC modules have a much less finicky op-amp and better compensation (phase margin) in the circuit.
I regret I did not notice right away that you had the old AVCC module.
Russ,
my OPA2209 and OPA2211 have arrived...
I'll drop either one in later today and take those 100pF compensation caps out - I will report how it turns out.
Cheers,
Max
my OPA2209 and OPA2211 have arrived...
I'll drop either one in later today and take those 100pF compensation caps out - I will report how it turns out.
Cheers,
Max
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I replaced the LMP7732 with a OPA2211 and removed the compensation caps.
Working like a charm, no noise!
Is is worth replacing the OPA209 with a OPA211 on the Tridents ?
Working like a charm, no noise!
Is is worth replacing the OPA209 with a OPA211 on the Tridents ?
No. IMHO, replacing 209 with 211 is just a waist of time and money. Tridents are performing fine as they are now.
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