Recent content by bButcher
  1. bButcher

    New Audio-gd R-7, R-7HE R-8, R-27, R-27HE, R-28 Flagship Resistor Ladder DACs and DAC/amps

    For easier comparison, 1uV on Terminator (4.6V xlr) roughly corresponds to 133dB.
  2. bButcher

    Audio-Gd Master 7 - Discrete Fully Balanced DAC (PCM1704)

    Desoldering of delicate IC like 1704 need strict control of temperature and heating duration, and even if it functions normally after the whole process it still could experience performance degradation due to thermal stress it went through. So I understand why Kingwa won't do it. As to the...
  3. bButcher

    Audio-Gd Master 7 - Discrete Fully Balanced DAC (PCM1704)

    Since I fixed the digital board last year, this is the only left major complaint I have with my M11. I've long been suspicious its related to analogue boards, thanks for verify it for me. Four months ago I shoot Kingwa an email asking the possibility of providing a "push-pull output stage...
  4. bButcher

    Audio-Gd Master 7 - Discrete Fully Balanced DAC (PCM1704)

    O.K. I'll try to clarify things a little with a picture: (1) Why only BCLK matters: please refer to PCM1704 datasheet page 7 & FIGURE 1. --- "The change in the output of the DAC occurs at the rising edge of the 2nd BCLK after the falling edge of WCLK." (2) BCLK* output from DSP is generated...
  5. bButcher

    Audio-Gd Master 7 - Discrete Fully Balanced DAC (PCM1704)

    Not exactly. If you only want a taste of what it might bring to the table sonical-wise, the minimal mod will involve cutting one end of impedance-matching resistor (of BCLK) to PCM1704s and wires it directly to DDC output. Theory behind the mod: After study the datasheet of PCM1704 and I2S...
  6. bButcher

    Audio-Gd Master 7 - Discrete Fully Balanced DAC (PCM1704)

    Actually there is another upgrade path if you (1) only use I2S input (2) only use NOS mode (or upsampling using computer) (3) Have necessary DIY skill --- you can (almost completely) bypass DSP chip and use your low jitter DDC with I2S output to drive PCM1704s directly. This is the lowest...
  7. bButcher

    Audio-Gd Master 7 - Discrete Fully Balanced DAC (PCM1704)

    If you check the design, BNC input is routed to BB DIR9001 which can only handle up to 108k. All other inputs are routed to Wolfson WM8805 which can handle 192k. DIR9001 has better performance than WM8805 but lower input rate.
  8. bButcher

    Audio GD New NOS 7 2016 Edition Impression Thread

    I see, so you are referring to the "Reconstruction filter (post filter)" and it is implemented as 1st order analog filter, and both NOS and Master dacs have it since they share the same analog circuit boards. (Sorry I misinterpret your NOS dacs web pages, it kind of give me the impression the...
  9. bButcher

    Audio GD New NOS 7 2016 Edition Impression Thread

    Thanks for the explanation, that clarify things a lot.   One more question: Is the 6dB/oct filter implemented in hardware or DSP-1 processor?
  10. bButcher

    Audio GD New NOS 7 2016 Edition Impression Thread

    Nice job.   The one marked LEJ#0Z is ADP150; the other two marked "L337" are generic 3.3V LDO --- can't locate the brand. I replaced both with ADP150s.
  11. bButcher

    Audio GD New NOS 7 2016 Edition Impression Thread

    Hi Kingwa,   Can you explain a little bit about the new Nos mode. Figure every one in this forum will very much like to know.
  12. bButcher

    Audio GD New NOS 7 2016 Edition Impression Thread

    Thanks for this information.
  13. bButcher

    Audio GD New NOS 7 2016 Edition Impression Thread

    Yes, you're right.   So next time I mention BYPASS option, I should add "Try at your own risk!!". Since Kingwa never warn me of any adverse effect, figure at least it won't burn your DAC. --- I've used this setting for couple of  months and also have the 98.3Mhz TCXO removed from my DAC.
  14. bButcher

    Audio GD New NOS 7 2016 Edition Impression Thread

    In I2S spec. there are three mandatory signals:   WCLK (word clock, or left right clock (LRCLK)) - 44.1k, 48k, 88.2k, etc. BCLK (bit clock) - usually WCLK x 2 x 32 in most implementation DATA (data) - include left and right channel data   MCLK (master clock) is optional, it is usually used...
  15. bButcher

    Audio GD New NOS 7 2016 Edition Impression Thread

    My is a NOS11, never has a M11 for comparison so can't say for sure. My guess is yes, both will work and sound similarly in BYPASS mode with one difference: M7 can only handle input up to 192k and NOS7 with new improved implementation can handle up to 384k. That could translate to less gates...
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