DuckToller Posted July 4, 2018 Share Posted July 4, 2018 Hi, did you lately had a look on your product page for the Micro iDac 2 ?https://ifi-audio.com/portfolio-view/micro-idac2/ Looks kinda (un)healthy ... regards & get well soon Tom Link to comment
AMR/iFi audio Posted July 5, 2018 Share Posted July 5, 2018 On 7/4/2018 at 5:06 PM, DuckToller said: Hi, did you lately had a look on your product page for the Micro iDac 2 ?https://ifi-audio.com/portfolio-view/micro-idac2/ Looks kinda (un)healthy ... regards & get well soon Tom Was it our site or your browser playing tricks on you ? ? Our PowerStation is here: click me! Check out our Tidal MQA Set-up Guides below. Android (Renderer) MobileDesktop (Decoder) via USBDesktop (Decoder) via SPDIF Link to comment
mansr Posted July 5, 2018 Share Posted July 5, 2018 54 minutes ago, AMR/iFi audio said: Was it our site or your browser playing tricks on you ? ? It was (is?) your site. You'd get that pharma spam if loading the URL directly without your session cookie set. Navigating there through the menu returned the correct page. DuckToller 1 Link to comment
asdf1000 Posted November 21, 2018 Share Posted November 21, 2018 Question for @mansr about the iDAC2 and DSD1793 “There the Burr Brown DSD 1793 d/a-conversion chip. It a remarkable device that does DSD natively. For PCM the top 6 bits are done using a ladder converter while the lower ones are done using a multibit converter. This means that it gets precision for the upper 6 bits from the precision of the resistors in the ladder converter as where for the lower bits the precision is determined by the precision of the clock. In DSD mode only the clock precision is determining the precision.” What does “the upper 6 bits” mean/refer/relate to? Is it related to the upper frequencies of the music? Or the “loudest” parts? And then the same for the lower bits - what is that? I guess the answer to the top 6 bits will help to understand the lower bits. Asking here in the iDAC2 thread but I guess this relates to all iDSD models since all use the DSD1793. Cheers in advance Link to comment
mansr Posted November 21, 2018 Share Posted November 21, 2018 1 minute ago, Em2016 said: Question for @mansr about the iDAC2 and DSD1793 “There the Burr Brown DSD 1793 d/a-conversion chip. It a remarkable device that does DSD natively. For PCM the top 6 bits are done using a ladder converter while the lower ones are done using a multibit converter. This means that it gets precision for the upper 6 bits from the precision of the resistors in the ladder converter as where for the lower bits the precision is determined by the precision of the clock. In DSD mode only the clock precision is determining the precision.” That doesn't make a lot of sense. 1 minute ago, Em2016 said: What does “the upper 6 bits” mean/refer/relate to? Is it related to the upper frequencies of the music? Or the “loudest” parts? And then the same for the lower bits - what is that? I guess the answer to the top 6 bits will help to understand the lower bits. The datasheet offers this explanation: "Digital input data via the digital filter is separated into 6 upper bits and 18 lower bits. The 6 upper bits are converted to inverted complementary offset binary (ICOB) code. The lower 18 bits, in association with the MSB, are processed by a five-level third-order delta-sigma modulator operated at 64 fS by default. The 1 level of the modulator is equivalent to the 1 LSB of the ICOB code converter. The data groups processed in the ICOB converter and third-order delta-sigma modulator are summed together to an up to 66-level digital code, and then processed by data-weighted averaging (DWA) to reduce the noise produced by element mismatch. The data of up to 66 levels from the DWA is converted to an analog output in the differential-current segment section." asdf1000 1 Link to comment
asdf1000 Posted November 21, 2018 Share Posted November 21, 2018 15 minutes ago, mansr said: That doesn't make a lot of sense. The datasheet offers this explanation: "Digital input data via the digital filter is separated into 6 upper bits and 18 lower bits. The 6 upper bits are converted to inverted complementary offset binary (ICOB) code. The lower 18 bits, in association with the MSB, are processed by a five-level third-order delta-sigma modulator operated at 64 fS by default. The 1 level of the modulator is equivalent to the 1 LSB of the ICOB code converter. The data groups processed in the ICOB converter and third-order delta-sigma modulator are summed together to an up to 66-level digital code, and then processed by data-weighted averaging (DWA) to reduce the noise produced by element mismatch. The data of up to 66 levels from the DWA is converted to an analog output in the differential-current segment section." Thanks but that still doesnt help me to understand what Thorsten @AMR/iFi audiomeans by “the upper 6 bits of PCM delivers slam”: “It uses a 6 Bit Multi-bit DAC for the upper 6 Bits of PCM Audio and delivers the warmth and slam Burr Brown Multi-bit DAC’s are so famous for. Any bits below this are converted with a low order 256 Speed Delta Sigma modulator (in effect DSD256), giving PCM playback the smoothness Delta Sigma DAC’s and DSD are famed for. https://www.audiostream.com/content/qa-thorsten-loesch-amrifi-audiostream-addendum-pcm-vs-dsd#HT2PWoCcI5zLIRXP.99 How does the upper 6 bits = slam? What is the upper 6 bits that Thorsten and the datasheet refer to? Does it relate to upper frequencies? The loudest parts? What parts of the music are the upper 6 bits? I’m trying to understand how upper 6 bits relates to slam. Thanks again Link to comment
mansr Posted November 21, 2018 Share Posted November 21, 2018 15 minutes ago, Em2016 said: What is the upper 6 bits that Thorsten and the datasheet refer to? The top 6 bits of each PCM word. 16 minutes ago, Em2016 said: I’m trying to understand how upper 6 bits relates to slam. It's marketing nonsense. Ignore it. Link to comment
asdf1000 Posted November 22, 2018 Share Posted November 22, 2018 10 hours ago, mansr said: The top 6 bits of each PCM word. It's marketing nonsense. Ignore it. Hehe thanks. So there's no relationship between "the top 6 bits of each PCM word" and how that affects dynamics/time domain performance etc? That's what I assumed/guessed Thorsten means by "slam"? @AMR/iFi audio can you kindly ask the boss to help explain? While I'm asking in the iDAC2 thread, since all iDSD models use the DSD1793, it would help immensely. Link to comment
AMR/iFi audio Posted November 22, 2018 Share Posted November 22, 2018 7 hours ago, Em2016 said: Hehe thanks. So there's no relationship between "the top 6 bits of each PCM word" and how that affects dynamics/time domain performance etc? That's what I assumed/guessed Thorsten means by "slam"? @AMR/iFi audio can you kindly ask the boss to help explain? While I'm asking in the iDAC2 thread, since all iDSD models use the DSD1793, it would help immensely. It's already been said, please take a look here: https://www.audiostream.com/content/qa-thorsten-loesch-amrifi ... and here: https://www.audiostream.com/content/qa-thorsten-loesch-amrifi-audiostream-addendum-pcm-vs-dsd Our PowerStation is here: click me! Check out our Tidal MQA Set-up Guides below. Android (Renderer) MobileDesktop (Decoder) via USBDesktop (Decoder) via SPDIF Link to comment
asdf1000 Posted November 22, 2018 Share Posted November 22, 2018 3 minutes ago, AMR/iFi audio said: It's already been said, please take a look here: https://www.audiostream.com/content/qa-thorsten-loesch-amrifi ... and here: https://www.audiostream.com/content/qa-thorsten-loesch-amrifi-audiostream-addendum-pcm-vs-dsd I've actually quoted those articles above... they don't explain how "the upper 6 bits" relates to more slam though... Link to comment
mansr Posted November 22, 2018 Share Posted November 22, 2018 Slam is emphasised bass. The DAC chip in question has, like all modern DAC chips, flat frequency response. The split architecture is just the method chosen by the designers for achieving their performance goals. So-called slam has nothing to do with it. asdf1000 1 Link to comment
Hugo9000 Posted November 22, 2018 Share Posted November 22, 2018 He's saying the warmth and slam are inherent in the TI/Burr-Brown multi-bit chip, not that it is inherent in the top 6 bits themselves. And then he claims that using Delta Sigma for the lower bits gives them the "smoothness" that is supposedly inherent in DS. So marketing can thus claim that they get the best of both worlds by using a hybrid approach! lol So, this begs the question, do TI/Burr-Brown chips have warmth and slam? Also, does Delta Sigma inherently have smoothness? And can combining approaches actually give the desired qualities of the two approaches? And what ratio works best? Now, if the different chips in themselves produce a different sound, I suppose it would make sense that whichever approach handles the highest bits would have the predominant effect on the overall sound, so their approach would then have more "slam and warmth" as a result of having the TI chip "on top" (that is, if these chips actually have such characteristics in the resulting sound). Having the "smoothness" effect added by DS handling the lower bits, on the other hand...perhaps they have done extensive blind testing which has shown that smoothing can be increased by 4.8% while only reducing the "slam" by 17.1%, which was the optimal compromise, resulting from their chosen ratio of bits for each approach. Originally, they had tried having the TI/BB on the bottom, with DS on the top bit only, but that resulted in reducing slam by 94.3%, which obviously didn't please any of their test subjects. Additionally, DS on the top for any number of bits greater than one had the dreaded effect of adding at least 3 veils for the first additional bit, and increasing exponentially from there. Bear in mind that the above are simply my "theories*" on what occurred in their blind testing (which they may not have even conducted haha), as I was not a participant. *aka, "wild ass guesses," which have as much in common with actual theories as anything in audio marketing speak. asdf1000 1 请教别人一次是5分钟的傻子,从不请教别人是一辈子的傻子 Link to comment
Popular Post mansr Posted November 22, 2018 Popular Post Share Posted November 22, 2018 1 hour ago, Hugo9000 said: He's saying the warmth and slam are inherent in the TI/Burr-Brown multi-bit chip, not that it is inherent in the top 6 bits themselves. And then he claims that using Delta Sigma for the lower bits gives them the "smoothness" that is supposedly inherent in DS. So marketing can thus claim that they get the best of both worlds by using a hybrid approach! lol It's all just marketing spin around the architecture of the DAC chip they happened to choose. Note that TI/BB themselves are not making any claims of this nature. 1 hour ago, Hugo9000 said: Now, if the different chips in themselves produce a different sound, I suppose it would make sense that whichever approach handles the highest bits would have the predominant effect on the overall sound, so their approach would then have more "slam and warmth" as a result of having the TI chip "on top" (that is, if these chips actually have such characteristics in the resulting sound). It's a single chip. The hybrid architecture is implemented inside the DSD1793 chip. See the figure from the datasheet I posted earlier. The actual advantage of the split approach is that it lowers the level of the modulator noise. asdf1000 and Hugo9000 1 1 Link to comment
Hugo9000 Posted November 22, 2018 Share Posted November 22, 2018 I never said that TI/BB have made any such claim about their chips. 请教别人一次是5分钟的傻子,从不请教别人是一辈子的傻子 Link to comment
mansr Posted November 22, 2018 Share Posted November 22, 2018 24 minutes ago, Hugo9000 said: I never said that TI/BB have made any such claim about their chips. Sorry, I didn't mean to imply you had. Hugo9000 1 Link to comment
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now