- #56 [alphability], 10-06-20 21:22尋找新主人中。。。
- #55 [alphability], 10-06-01 14:38Blackgate (NONPOLAR)
- #54 [alphability], 10-06-01 14:37ELNA
-
- #53 [GaryL], 10-05-22 11:58我部Quad 405-2都想換OPAMP/Recap. 有冇C-Hing可以代幫手^^
- #52 [alphability], 10-04-29 01:26RECAP RECAP RECAP
聽過 LS3/5a BASS 打心口未， 功勞歸 M
不過德國製品，SOMEHOW破壞QUAD英國聲底 :P
（註: 我反對人地用M， 應用新一代BHC)
- #51 [alphability], 10-04-29 01:22CAP CAP CAP
"...Two ~100nF-caps (here cheap ceramics are first choice!) from the OpA's powersupply
pins (7 and 4) to ground (pin 3 in this case) are imperative. Otherwise most of
the 'modern' Audio-OpAs will have a tendency to ringing or even to rf-oscillation
(despite their better PSR-ratios!)..."
- #50 [alphability], 10-04-29 01:17聲音通透無比 OpAmp BB OPA604AP,
降低OpAmp放大率， 對聲音好重要!!
Note from BerndFritzLudwig
"To reduce gain of the input-stage...Local feedback: Close to the OpA there is one MKT-capacitor C4 =47nF connected
to R6=330k. Add [1] C4'=100nF (same type) across C4. Add [2] R6'=150k across
R6=330k.
Overall feedback: Two 22k-resistors are connected to pin 2 (inverting input of the OpA): R3 which leads to the input cap C1=0.68uF and R4=22k which leads to C2=100uF. Add [3] R4'=10k across R4=22k (not across R3!)..."
- #49 [alphability], 10-04-29 01:07每次打開QUAD 都有陣 松香膏 氣味,是英國獨有
(最惡頂十年前國內電器松香膏氣味會流眼水)
- #48 [alphability], 10-04-29 01:01so fast, one year now, let me do some update here.
I did the OpAmp Mod based on the following article:
http://quad405.com/405mods4.pdf - #47 [alphability], 09-05-09 01:01香港市電實在太噪
要執執先
背景靜到呢～～～ ^.^
- #46 [alphability], 09-05-07 01:14開聲!
高音通透得很!
中音人聲冇大改變 ^^"
低音清楚繼而薄了一點, 不過感覺快 非常 HIFI
最重要, QUAD 那份 MUSICAL 依舊保留 - #45 [alphability], 09-05-06 22:29cheap ceramics? 用WIMA都唔係好貴
- #44 [alphability], 09-05-06 22:26TL071 OPAMP 實在太舊， 電源最簡單方式補償
QUAD-405 Modification (and related stuff), version 1/2004
"...Two ~100nF-caps (here cheap ceramics are first choice!) from the OpA's powersupply
pins (7 and 4) to ground (pin 3 in this case) are imperative. Otherwise most of
the 'modern' Audio-OpAs will have a tendency to ringing or even to rf-oscillation
(despite their better PSR-ratios!)..."
http://quad405.com/405mods4.pdf - #43 [alphability], 09-05-06 21:37為保存 QUAD 原聲， 只改 OPAMP
其他零件完整保留
- #42 [alphability], 09-05-06 20:41原裝 英國製造 TI TL071CP (原來 TI 當年英國有廠房製造IC)
新歡 泰國製造 BB OPA604AP
- #41 [alphability], 09-04-19 00:25QUAD OFFICIAL REPLY!
THEY ARE EXTREMELY HELPFUL!
- #40 [alphability], 09-04-04 00:45成功改香港市電
開聲開心到無朋友
多謝各界頂力協助！
下一部， 返回黑膠 ^o^ - #39 [39hkw59], 09-03-29 00:26Hi Alphability:
閣下部機改好末呀! - #38 [lfyeung], 09-03-27 20:49ALPHABILITY兄,
有,我剪咗二條jumper,声音好似好咗.
LFYeung - #37 [alphability], 09-03-26 23:49lfyeung 兄
您有無將那兩條 jumper 線 拿走?
- 下一頁 (1 of 3)
- 返回 ...
回覆(39): 我部QUAD 405.2 要改 (2)