raspberry pi 3 + RuneAudio

tcgtam

djaddy 發表於 2016-4-28 00:11
Pls have a look at this first:

http://post76.hk/forum.php?mod=viewthread&tid=238428&extra ...

........師兄你可真是另類毒人, 真是天外有天, 人外有人, 沒有最毒, 只有更毒 (最要命的是連機器相片都是後現代派的 )

問題一: 談回那個usb filter, 是否跟以下的商品相似?
1. AudioQuest Jitterbug USB Filter: http://www.audioquest.com/jitterbug/jitterbug
2. AudioQuest Diamond USB cable上的那個DBS: http://www.hifiplus.com/articles ... d-usb-cable/?page=3

問題二: 貪心的再問, 有發燒友認為 Ethernet cable 都會影響到音質, 你認為如何? 我覺得如果播放器和USB DAC 以USB 線相連並且行Async mode, 而USB DAC 本身有獨立供電, 我們該擔心的應該是條USB 線有否data lost, 而不是播放器那邊的內部多了個Ethernet 而造成的干擾吧?

先行謝過    

djaddy

tcgtam 發表於 2016-4-28 00:45
........師兄你可真是另類毒人, 真是天外有天, 人外有人, 沒有最毒, 只有更毒 (最要命的是連機器相片都是 ...

玩 hi-fi 千萬不要"妹仔大過主人婆". Audioquest products 係好，但記你隻 Pi3 先係幾錢。買名牌usb綫会貴過你隻 Pi3。 講真，你部 TEAC 已經超越部 Pi3太多， 有d唔平衡。

我淘受 usb filter 才是幾十。用垃圾 tune 到好声才是高手。

真正嘅 Cat6 LAN 綫 spec 其實己經好高， 真係要買貴嘢？
(Post76 Android 手機版送出)

tcgtam

djaddy 發表於 2016-4-28 01:17
玩 hi-fi 千萬不要"妹仔大過主人婆". Audioquest products 係好，但記你隻 Pi3 先係幾錢。買名牌usb綫会 ...

首先，小弟是做IT的, 編寫程式是我的強項, 所以對電腦端的資料處理方法算是有點心得.

我認為玩音響, 講的是怎樣將錄音室錄到的聲音原原本本的還原出來. 問題就是, 不管你用任何物資傳送資料, 總會有所謂的data loss. 所以, 以前(純analog)玩音響, 的確是多隻香爐多隻鬼, 多條線就多點data loss. 所以, 靚線材在科學上都是合理的.

但去到CAS 呢? 聲音資料在DAC之前, 都是用數碼(digital)方法做傳輸的, 所謂數碼傳輸可以做到完全沒有data loss 麼? 答案是可以, 但不是因為digital線沒有data loss, 只是因為數碼傳輸支援error detection and error correction (data resend) 而已. 試想一下, 現今錢銀交易事情都是由電腦網絡傳送資料, 你能夠容忍傳入你銀行戶口的銀碼因data loss 而少了一個零嗎?  總之, 數碼資料的傳輸能夠零失真, 不是因為線材, 是因為機制.

那麼當我們講到連接NAS 和播放器的LAN 線是否需要高級? 我認為是沒需要, 因為有error correction/resend 機制嘛. 只要供data 給DAC的那個位有足夠的buffer就成了

那麼USB線又如何? 奈何, USB audio 的傳送是用isochronous mode 的: http://www.keil.com/pack/doc/mw/ ... ous__transfers.html , 即是, error correction/resend 機制沒有了. 那麼, USB 線的質素又變得重要了, 既然不可能修正錯誤, 就只能減少出錯機會啦(即是要靚USB線啦).

我覺得"妹仔大過主人婆"這概念是源於純analog時代, 因為那時所有錯都不能修正! Pi 3做的都是左手交右手的東西, 不牽涉轉換, 又能改錯, 它價錢便宜是應份的!

djaddy

tcgtam 發表於 2016-4-28 03:51
首先，小弟是做IT的, 編寫程式是我的強項, 所以對電腦端的資料處理方法算是有點心得.

我認為玩音響, 講 ...

What a coincidence, I work in the IT industry, too. I graduated from Electrical & Computing Engineering;  worked in the Telecommunications field  and gradually moved to IT infrastructure and started my own firm 5 years ago. Also worked as a DJ for more than 10 years during high school thru my uni years for an ethnic radio station; I started with Wheel to Reel to recording songs on my MD player back in the day.

So what do I know about data loss & analog audio systems? One thing I have learned is that Proof Of Concept (P.O.C.) is the most critical. Let me give you an example, quite a few years ago when everyone were switching to HDMI cables, there were lots of discussion that more expensive HDMI cables are no better than cheaper ones because the signals were digital. The cheaper HDMI cables will not have data loss over the same distance. Even CNET published an article on this at the time. Yet, there was a group of audiophiles who swore on their mothers' graves that the more expensive HDMI cables do perform better for both visual & audio. I then purchased a $200 Monster HDMI cable and a 1 meter VDH HDMI cable at $1400 from UK, also borrowed quite a few different ones. After extensive testing, I concluded the audiophiles were correct. Despite there were no data loss with cheaper HDMI cables, the materials used for each individual cables were different. The conductors and damping materials used in each cable will influence your visual/ audio experience. I am still using my VDH HDMI cable... & I have no idea where that Monster HDMI is now... lol.

My recommendation of "妹仔吾好大過主人婆" has nothing to with the analog or digital ages. At school, they never taught us why we need to "run-in" my HDMI cables for 200 hours nor how different conductors have their own visual/ audio characteristics. Why did I choose red-cooper power plugs for my DAC, pre-amp, & power-amp while I picked gold for my desktop computer? Why use a SSD HDD? Why do I need my power cables to 灌沙? Why do I have separate power bars for my monitors & audio components? Why did I put leather underneath my speakers? Why use OCC and not OFC? Do all these belong in the analog age or the digital age? What is important to me, it's the harmony of all these components existing together to provide the visual/ audio experience to my liking (with a budget that makes sense).

My 2 cents...
  

tcgtam

djaddy 發表於 2016-4-28 06:28
What a coincidence, I work in the IT industry, too. I graduated from Electrical & Computing Engine ...

看你那些post, 就知你是有(超級發燒)過去的人.

所謂"信自己的耳朵", 其實可以用中國人的哲學(嚴格來說應是佛學)去演繹: 古典中國人為什麼不著重科學精神? 不是因為中國人蠢, 是因為中國自孔子起已相信人不能突破天 (自然定律), 沒有人能做到全知, 只能與大自然和諧共存. 所以傳統中國人不會用white box 的方法去看事情, 只會重觀察(信耳朵!) 而不剖析. 背後的理念是, 世事萬物因中有果, 果中有因, 因果互相糾纏, 很多事情根本不可能用線性邏輯去解釋.

一套系統, 要一竹桿的解釋為什麼不靚聲, 就像要解釋為什麼香港現在這麼不濟一樣: 有理說不清, 亦沒有人真的知道真相. 其實跟怎樣才能令人變得健康一樣, 要怎樣才能靚聲, 無論人發明的科學系統多精密, 都沒法靠科學得到100%答案. 所以去到尾, 人只能早睡早起身體好, 用耳朵去追尋靚聲.

回到正題, 究竟你那個USB 淨化器的用法是否跟AQ 的jitterbug 一樣? 我看應不是吧, 兩邊好像是不同制式的USB 頭.....? 上淘寶用 "USB 淨化器" 之類的字眼都找不著重$100 左右的貨呢......? 先行謝過.

djaddy

tcgtam 發表於 2016-4-29 02:17
看你那些post, 就知你是有(超級發燒)過去的人.

所謂"信自己的耳朵", 其實可以用中國人的哲學(嚴格來說應 ...

"We cannot solve our problems with the same thinking we used when we created them."

Your key words are, "USB EMI噪声抑制器."
(Post76 Android 手機版送出)

tcgtam

djaddy 發表於 2016-4-29 08:18
"We cannot solve our problems with the same thinking we used when we created them."

Your key word ...

哈, 用那個思維的話, 要解決不靚聲的最好方法就是"木耳"

那USB EMI filter，淨化data 線上的interference之餘, 又能否用來淨化我Pi3 的電源?

adktk

wkw9811 發表於 2016-4-27 02:45
alexyuman 兄,

謝謝通知,

我的 C2 今天 (30/4) 已到我手上了。

djaddy

tcgtam 發表於 2016-4-29 12:38
哈, 用那個思維的話, 要解決不靚聲的最好方法就是"木耳"

那USB EMI filter，淨化data 線上的interferenc ...

The USB filter can only filter the power from the USB port. "淨化 Pi3 的電源" is a separate topic. Regarding power for audio components, pls carefully considering my previous question, "Why do I have separate power bars for my monitors & audio components? " I am sure I can shared about this in my previous posts. To further this, pls research on 地盒, also.

The answer you seek regarding the USB filter lays with the search "USB EMI噪声抑制器" in Taoboa.

P.S. Pls respect the words from the great Albert Einstein, I do not find his words a laughing matter.

wkw9811

adktk 發表於 2016-5-1 01:20
我的 C2 今天 (30/4) 已到我手上了。

您可能早了我點訂, 按我以往經驗,
她們4個工作天便可發貨, 我的應該下星期二便收到。

因為平, 音質不錯, 我每次訂都 5 張以上, 介紹朋友玩玩。
有否訂埋 Remote 同 DC cable?

這兩天新 image for C2 會出, 會支援 WaveShare 7" IPS panel, 正到爆