第2頁,共6頁 第一第一 1234 ... 最後最後
顯示結果從 11 到 20 共計 59 條
  1. #11
    註冊日期
    2007-05-03
    文章
    72,593
    Thanks
    7,665
    Thanked 20,844 Times in 9,306 Posts

  2. #12
    註冊日期
    2009-11-10
    文章
    97
    Thanks
    2
    Thanked 11 Times in 6 Posts

    預設

    這個transport就是美國官網的memory player吧?

  3. #13
    註冊日期
    2007-05-03
    文章
    72,593
    Thanks
    7,665
    Thanked 20,844 Times in 9,306 Posts

  4. #14
    註冊日期
    2007-05-03
    文章
    72,593
    Thanks
    7,665
    Thanked 20,844 Times in 9,306 Posts

    預設

    FPGA架構,10倍DSD升頻

    DirectStream除了是DAC外,還具有前級功能,其由主要設計者Ted Smith、PS Audio總裁Paul McGowan及Infinity的創辦人Arnie Nudell共同研發。其主要使用了FPGA (Field Programmable Gate Array)為其主要的處理核心,而非直接使用市面上的晶片,目前只有極少數幾家是採用這種方式,通常以FPGA設計的DAC,聲音表現都能讓我有很好的印象。

    DirectStream對不同輸入來源所造成聲音的影響都能夠維持一定的聲音水平,關鍵就在於其使用了一種極快速進行取樣頻率及辨識的專利方法,並且也能對線材不同、時基誤差與資料品質所造成的差異影響降低。只要聲音訊號進到DirectStream,就會自動升頻到DSD 2.8MHz的10倍取樣,最後再輸出DSD 5.6MHz及使用「被動」濾波類比級。

    DirectStream完全是使用DSD的架構,即使輸入是PCM,也會升頻為10倍的DSD,採用DSD為核心的主要原因:
    1. DSD轉換成類比比較直接,只需低通濾波器。
    2. DSD本質上就是是線性的,PCM架購要做相同的電壓值是比較困難的。
    3. DSD 在超出規格範圍的部份,只有輕微的影響,但是PCM在超出規格範圍時的影響會比較大。
    4. DSD所有的位元權重是一樣的,單一位元的錯誤是不容易被測量與聽到的,而PCM的某些位元權重要高,有可能會產生較大的問題。在固定S/N下,PCM需要更多的錯誤復原處理。
    5. 許多PCM的器材事實上使用的是sigma-delta modulator (DSD) DAC晶片,許多的A/D轉換也是以sigma-delta為基礎,典型的PCM轉換路徑是analog -> DSD -> PCM -> disc -> PCM -> DSD -> analog,DSD的方式就可以不用再透過PCM,減少了轉換時所產生的問題。
    6. DirectStream處理各個輸入來源的PCM轉換,並不需要去重新找到時鐘訊號,而是透過資料內容的辨識,這樣一來,輸入的時基誤差就不會出現在FPGA中。



    Send from Sony Z2 by tapatalk app

  5. The Following 2 Users Say Thank You to Leo Yeh For This Useful Post:


  6. #15
    註冊日期
    2007-05-03
    文章
    72,593
    Thanks
    7,665
    Thanked 20,844 Times in 9,306 Posts

    預設

    內部公開

    拆開外殼是需要特殊工具與技巧的,自己可別輕易嘗試!
    很明顯的,左邊搭配DVD-ROM是PerfectWave CD/DVD Memory player,右邊則是DirectStream DAC



    Coming....


  7. #16
    註冊日期
    2007-06-07
    文章
    3,243
    Thanks
    3,174
    Thanked 2,972 Times in 1,404 Posts

    預設

    有新的DirectStream firmware update http://www.psaudio.com/forum/directs...just-released/

    據說好的嚇人!特別是低頻的部份。照McGowen的說法,趕快把手邊的事情放下,去下載這個新軟體。。。。。

  8. The Following 2 Users Say Thank You to kevintran For This Useful Post:


  9. #17
    註冊日期
    2007-05-03
    文章
    72,593
    Thanks
    7,665
    Thanked 20,844 Times in 9,306 Posts

    預設

    release version 1.2.1 : 聲音有明顯提升!

    After much work on the part of Ted Smith and the evaluation team, we officially release version 1.2.1; the single biggest improvement to DirectStream yet.


    Here's a little backstory. We've had Ted locked away in his development lab for some time now, brewing up new improvements to DirectStream. As owners of DirectStream know, this is a product where the word 'obsolete' doesn't apply. Cannot apply.

    DirectStream is really nothing more than a beautifully built hardware platform with state of the art power supplies feeding an FPGA, its performance, its sound quality, its entire DNA, can be changed via a simple downloaded file. In other words, we can email a new product to owners anywhere in the world.
    Obsolescence, is now obsolete.

    Ted had a number of truly advanced ideas he was toying with and in the middle of working on. Then came the review in Stereophile where Atkinson pointed to a bit of distortion in the lower bass. We sat around the engineering meeting discussing ideas for lowering that level. None of us really felt it was sonically important, but it would still be nice to have the measurements look more like what people's expectations were like. Why not? Ted waved his magic wand, added his advanced thinking on improvements already in the works and bingo! We get 1.2.1.

    Our first indication this was something more than just another update came at Arnie's house. We fired up Ted's latest firmware and we both turned to each other in astonishment within the first three notes of Mahler's second. "What the hell?"

    The bass was magically transformed. Tightened up, firm, punchy, toe tapping. This was a shock because we really didn't think lowering the distortion would have much of a sonic change. Boy was I wrong on that one! But then the bigger surprise. The soundstage became magical in a way I've not yet heard any DAC, any system, perform. The degree of new layering, depth and openness really stunned us both. I would be remiss if I did not suggest this firmware places DirectStream in an entirely new class of DAC. To say 'you ain't heard DirectStream yet' is NOT an understatement.

    We prepared 40 versions of the code, each with small tweaks. Arnie and I personally went through each and every one of them and found the very best of them all. We then presented all this to our Beta testing group and gave them yet a few more choices in another area of code. After much cussin' and discussin' we arrived at 1.2.1. Wow.

    Lower noise floor, lower distortion levels yes. But most important, a MAJOR sonic improvement.
    And, as I hope all DirectStream owners appreciate, the upgrade is free. How many high end companies do you know of that modify every parameter of their product for you for free?

    Go here: http://www.psaudio.com/support…..downloads/ and download your copy of 1.2.1. Unzip the file, place the contents on a blank SD card, place that card in DirectStream and power cycle the unit via the rear panel power switch. The logo light on the front will blink for about 30 seconds, the unit reprograms itself and suddenly it is transformed. If you need help, the community members are here for you.

    You do not have to do anything else. It doesn't matter what firmware you start with, you can go directly to 1.2.1. If you wish, you can download earlier versions and go back to see the difference. Most of you will not need to.
    It's that good.

    http://www.psaudio.com/forum/directs...just-released/



  10. #18
    註冊日期
    2007-05-03
    文章
    72,593
    Thanks
    7,665
    Thanked 20,844 Times in 9,306 Posts

  11. #19
    註冊日期
    2007-05-03
    文章
    72,593
    Thanks
    7,665
    Thanked 20,844 Times in 9,306 Posts

    預設

    下載解壓縮後有這些檔案,存在SD記憶卡準備升級

    dailya0062.jpg

  12. #20
    註冊日期
    2007-05-03
    文章
    72,593
    Thanks
    7,665
    Thanked 20,844 Times in 9,306 Posts

發文規則

  • 不可以發表新主題
  • 不可以發表回覆
  • 不可以上傳附件
  • 不可以編輯自己的文章
  •