電池驅動 USB Reclocker 經驗分享

odysseyhk

電池驅動 USB Reclocker 經驗分享

一月份中收到 W4S Recovery USB Reclocker (RUR), 差不多三個月時間的試驗，終於Ready 同大家分享如何玩電以達到 潔淨 USB Signal。 實驗以 RUR 進行，不代表其他產品有相同的果效。 (申利: 我們為 Wyred4Sound (W4S) Product 香港代理)

1/ 電池驅動 vs LPS

比較過 Linear Power Supply + Buffering DC Power Filter, 電池是大比數勝出了。



但是電池電壓不足不穏定，及電池使用時間是個很重要的考慮。RUR 可以接受 6V-9V DC input.  內部有Regulator 以供RUR 內部及USB output 使用。這個設計令到用電池是可行的方案。

測試過用電量，以W4S DAC2 DSD 為例， Draw 大約170mA 的電流，以2000mAH 電池可以用十小時以上。 當然不同的DAC 用電量有所不同。



2/ 不同的電池是否不該一樣聲？  那種電池好聲D？ 為什麼？

做了一些研究，我認為電池的阻抗是重要的區別。

我曾試Panasonic 的 envelop 充電電池×6 A / B比較 鹼性電池×6 （Duracell） 。
Panasonic envelop 電池進行充電聽起來要好得

https://www.batteryspace.com/prod-specs/HR-3UTG_Spec-eneloop.pdf
http://www.farnell.com/datasheets/97133.pdf

Duracell is 181mOhm per cell. While Eneloop is 25mOhm.

對於6 cells 電池。金霸王總阻抗為1.086歐姆。 eneloop電池是0.15ohm 。電池的噪聲水平應該是相似的。因此，阻抗具有在數字音頻非常重要的作用。 我的看法是，對於數字電路，快速反應電源 支持快速“rise time”，lower jitter。



3/ 電池加電容會否大有改善？

Parallel 電容 加強快速反應，減少內阻，比只用電好得多。我喜歡這些低ESR電容的改善。



4/ 那種電容最好聲?

造了七個電池盒用7種不同的電容器 (Electrolyte & Aluminum Organic Polymer）

從左至右分別是:
1 - Rubycon Electrolyte Cap 6800uF
2 - Panasonic Electrolyte Cap 6800uF
3 - Panasonic OSCON (use 2 lower voltage capacitors 680uF in series)
4 - Panasonic OSCON SEP Series 680uF x 3
5 - Panasonic OSCON SEPC Series 470uF x 3
6 - Panasonic OSCON SEP Series 680uF x 1
7 -  Panasonic OSCON SEPC Series 470uF x 1

Outcome:
7 > 6 > 3 > 2 > 1

大致上 Lower ESR 是可以出到好D的效果，多咗感情，細節非常好而均衡。

- OSCON Low ESR Capacitor 在 Digital 方面表現是非常好，比 Electrolyte Low ESR Cap 優勝很多，就是 Electrolyte Cap 容量產品大十倍也沒有帶來優勢。  但是OSCON也不一定 絕對好的，有一個 Friend 帶來一個USB Powered DAC，由於 Digital + Analog 電路同時由USB Power 驅動，大電容比較鬆容。
- 同是OSCON 或  同是 Electrolyte, Lower ESR is better.
- 比較 Parallel OSCON capacitors x 3 會否改善, 結果有點失望，聲音冇咁穏定。



5/ USB Audio 三種 digital signal 補品

暫時最佳 USB Audio digital signal 是以下三種補品同時使用。


1 - W4S Recovery USB Reclocker (Femto Clock)
2 - Battery pack with Panasonic OSCON SEPC Series 470uF x 1
3 - USB Noise Terminator ( 吸收電腦5V Noise, 從  USB Chip 開始 gen clean USB signal)

測試 Music Records

Stockfisch Recording - 16/44.1 file.  Sara K. and Chris Jones live presentation is great.  Though it is 16/44.1, it is as good as any high resolution record.  Excellent recording and mastering.   Challenging the HiFi set up to re-produce the live feeling.


2L DXD recording "Come Away, Death" is sample record from 2L.  Excellent vocal and piano, reproducing the deep heavy feeling is what we want to observe.


Linn PCM 24/96 recording, very real female vocal.  Very useful to hear the difference of A/B audition.


DSD 128 - DIRECT DSD Recording - no PCM mixing.  Very pure sound (vocal and piano), good for audition reference.

lumgwa

Amanero USB 亦有相同情況.  一個獨立 5v LPS 供電及不上 4 粒 NiMH 叉電的音色來得自然通透.  其後在電池出線附近並了個普通的 .47uF, 亦有明顯進步.
此 USB board 在非工作狀態下, 是會從叉電池處消耗 78 mA.  在工作狀態下消耗 122 mA.
4 粒 1900mAH NiMH 在叉滿電並穩定後電壓約 5.56 v, 電壓下降至 4.36 v USB 才停止工作.
經記錄, 一次叉電可發燒16 小時.
我現在用兩組 1900 mAH 電, 撥掣輪流供電, 弱電那組留待停播音響時才用0.1 C (190mA) 慢叉 14 小時.
有群組是用 LiFePo4 電, 據說音色更勝 NiMH.  唔知有無 c Hing 可以分享.

obee

有沒有試過 Lithium ion 電池, 如A123 Lifepo4, 它的內阻很低.

SamPoon@FB

obee 發表於 2016-4-11 00:22
有沒有試過 Lithium ion 電池, 如A123 Lifepo4, 它的內阻很低.

難d,因為一組3.7v,充滿4.2,一組唔多,2組又太多,2組加整流又好似有d多餘

lumgwa

obee 發表於 2016-4-11 00:22
有沒有試過 Lithium ion 電池, 如A123 Lifepo4, 它的內阻很低.

怕如手機尿袋內電路影響質素, 無試過鋰電.
c Hing 有何建議.

obee

呢件野話係食5V, 但一般好多IC都只係3.3V或更低, 所以好可能用3.2V的鋰鐵電, 如2500mah的, 一粒接入盒內的5V>>3.3V regulator 輸出位. 直接.
不過也可能它有些零件是行5V的, 只是機會不大.

lincoln

嘩由LPS再向電池進化

kc7

obee 發表於 2016-4-11 07:27
呢件野話係食5V, 但一般好多IC都只係3.3V或更低, 所以好可能用3.2V的鋰鐵電, 如2500mah的, 一粒接入盒內的5 ...

可唔可以 3.2V x 2(兩粒) >> 5V regulator?

obee

kc7 發表於 2016-4-11 09:49
可唔可以 3.2V x 2(兩粒) >> 5V regulator?

過粒regulator唔好聲的, 可以試下.

obee

lincoln 發表於 2016-4-11 09:43
嘩由LPS再向電池進化

LPS係有效, 但應該case by case去睇, 如果大電流, 長開, 一定用LPS最好.
如果細電流, 唔使長開, 用電池可能較好.
呢個reclocker, 話170mA, 其實唔細, 希望真係行3.3V, 咁電流應該更細.

kc7

obee 發表於 2016-4-11 09:57
過粒regulator唔好聲的, 可以試下.

咁手機充電池5V直入效果可以嗎?

obee

kc7 發表於 2016-4-11 10:22
咁手機充電池5V直入效果可以嗎?

手機充電池5V 係用一粒 Lithium-ion (3.7V) 升壓做5V的, 當然唔好.

kc7

obee 發表於 2016-4-11 10:45
手機充電池5V 係用一粒 Lithium-ion (3.7V) 升壓做5V的, 當然唔好.

Thanks....

odysseyhk

obee 發表於 2016-4-11 09:58
LPS係有效, 但應該case by case去睇, 如果大電流, 長開, 一定用LPS最好.
如果細電流, 唔使長開, 用電池可 ...

Agree.  

W4S Recovery USB Reclocker 由於要供電給DAC，Output Current 要視乎DAC Draw 幾多電，  170mA 只是測試數據。問過大部份用家都能用十小時以上。 只有一個用家的DAC完全由USB供應電力，電池只能用6個小時。

odysseyhk

obee 發表於 2016-4-11 00:22
有沒有試過 Lithium ion 電池, 如A123 Lifepo4, 它的內阻很低.

Nano-tech LiFePO4 battery 6.6V, internal resistance < 10mohm.  The high end model actual claim to be 1mOhm.   May give it a try.  (RUR support 6-9V input, so 6.6V is ok)  Nano-tech battery is designed for high current use.   Given my experience with multiple capacitors in parallel not working well, the construction and design is important, not just the internal resistance rating.  So need to try before we know if it is good.  

If anybody bring it in, will try it and have fun.

Siuping

lumgwa 發表於 2016-4-11 00:05
Amanero USB 亦有相同情況.  一個獨立 5v LPS 供電及不上 4 粒 NiMH 叉電的音色來得自然通透.  其後在電池 ...

師兄的 Amanero 是自己 DIY 的獨立 module? 可以分享用什麼 dac?

obee

lumgwa 發表於 2016-4-11 00:05
Amanero USB 亦有相同情況.  一個獨立 5v LPS 供電及不上 4 粒 NiMH 叉電的音色來得自然通透.  其後在電池 ...

Amanero 用3.3V的, 只要把3.2V lifepo4放在中間果個三孔(P3 的#1和#3 pin)中的頭尾便可.
另外, 我建議cut左輸入的L1, 否則你的USB線不要有5V電, 或者甩左U2
我會把C27接一隻5V relay, 若有外來5V (USB線), relay 才把3.2V的lifepo4電接通, 這樣可以減少不必要的耗電, 也可令DAC在有USB線(有5V電時)才detect到amanero

S6Edge

IMHO battery's  noise are not much lower than cheapy switching power supplies.

odysseyhk

S6Edge 發表於 2016-4-11 20:39
IMHO battery's  noise are not much lower than cheapy switching power supplies.

Hi, More information about the noise level you are referring to as high would be useful.  Thanks.

The classical measurement of battery noise for reference.   Chemical reaction does generate ripples, and the low ESR capacitor parallel to the battery is useful.  

http://tf.nist.gov/general/pdf/1133.pdf

If you found a cheap switching power supply give better sound than battery in your environment, stay with it.  I'm sharing experience with my setup and we understand that each setup is different.  

obee

S6Edge 發表於 2016-4-11 20:39
IMHO battery's  noise are not much lower than cheapy switching power supplies.

I afraid that this is not a humble opinion, this is a discouraging view instead. To discourage others try something that you believe it is wrong, or not meaningful to do.

Well, audio experience is different to everyone, which includes lot of factors not just scientific figures. Those scientific factors are real, useful information to explain lot of situation why we have such audio experience. But clearly, they can't explain ALL the scenarios, each figure just can explain a certain aspect of the whole thing. It's like taking one photo on an object, it tells something but just from that perspective. It's not a 3D image after all, but human ear interpret this thing in 3D way.

To me, the sound quality from a cheap SMPS must be different with that from battery or LPS. They just different from our ears. Different may mean better or worse, everyone has different feeling, that is why we have some expensive hi-fi accessories because some people can hear the difference.

More on the battery structure, we have different kinds of lithium batteries, they have different internal structure that must affect the audio experience. Moreover, how you wire the whole thing matters. All in all this is a trial and error process, if not a random process, to try different ways of power supplies to something.