- #458 [wcw12], 21-12-21 11:29
- #457 [wcw12], 21-12-21 11:11羅密歐師傅講解到位!
所以胆前級以牛輸出又做到收中心抽頭(C.T)做法,那就分好了相啦。
這樣胆機前後級都以全平衡工作了。
更好是前級也具備600 C.T功能,配備600 C.T輸入牛,那就把大部份高級的CD Payer and DAC的ture balance功能發揮盡了。
以平衡方式工作在音響設備上,是最好的,平衡方式不止於在長距離傳送上才需要。下面提及的4件300B胆後級作為平衡工作推一對ATC喇叭,我在2016去拜訪Hitec黃先生時,他示範過給我聽,效果肯定! - #456 [bambino], 21-12-20 18:27明白, 又學到嘢. 多謝羅密歐師傅!
最後修改時間: 2021-12-20 18:28:16 -
- #455 [羅密歐], 21-12-20 17:43全對。
5) 輸出牛負端一般都是接地的,自然已經接通了。 - #454 [bambino], 21-12-20 17:03吾知有冇理解錯,是不是這樣....
1) 前級牛 +同地接去300B amp (1) 輸入端
2) 前級牛 -同地接去300B amp (2) 輸入端
3) 300B amp (1) speaker out+極接去speaker嘅+binding post
4) 300B amp (2) speaker out+極接去speaker嘅-binding post
5) 兩部amp嘅speaker out負極是否接連 ?
6) 兩部amp嘅4ohm speaker out接去8ohm speaker 嗎?
謝謝! - #453 [羅密歐], 21-12-20 16:47估計那賣家是經過牛,來分出正負相位,再入一對後級,喇叭就接在那一對後級的hot端。
以上講的,是單一個聲道,所以立體聲要用上四台monoblock. - #452 [bambino], 21-12-20 16:39#451, 羅師傅, 可否介紹吓兩部300B amps如可接成BTL ? 謝謝
- #451 [羅密歐], 21-12-20 16:26#445 那是BTL接法。
那賣家的所謂[串聯],並非一前一後的意思,他用的詞只是玩家用詞,而不是電學用詞。 - #450 [bambino], 21-12-20 16:23#449,
can it be done without 2 more inverter wothout No.1 ? find a way to feed 2 the single end stage ....inverted wiring( haha ) to 2 and 3 ...and add something in between or even done nothing just simple wiring .. ?
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no idea la. it's beyond my limited knowledge.
...why # 445 about 冇noise cancellation...
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you could connect your system this way, measure the noise level and compare the case with one 300B amp only
CDP -> Preamp -> 300B Amp -> 300B Amp -> Speaker (for one channel)
最後修改時間: 2021-12-20 16:24:57 - #449 [hahayanyan], 21-12-20 16:03#448
yes....yes..those 2 seconds wonder...is the things u said at 1,2,3,4,5...
can it be done without 2 more inverter wothout No.1 ? find a way to feed 2 the single end stage ....inverted wiring( haha ) to 2 and 3 ...and add something in between or even done nothing just simple wiring .. ?
如果兩個amp stage pick up嘅noise係一樣的的話, noise(A)-noise(B) = zero
目的是noise cancellation.
假設是noise(A) = noise(B)
this is why..my thought was..using dual triode...etc......least different parts as possible..
also feel "......用2部串聯推一隻喇叭效果不只升級一倍..."
這句話真係可圈可點
thx for teaching... i am a paper based learner..
i need to think...why # 445 about 冇noise cancellation...good to think think...
haha
最後修改時間: 2021-12-20 16:12:13 - #448 [bambino], 21-12-20 15:58#443 同 #445 講嘅係兩樣嘢 ......
如果我冇理解錯的話#443是指喺Line Amp度
1) 輸入訊號經Inverter產生一個反相訊號
2) 輸入訊號經amp stage (A) 放大,同時pick up一些noise(A)
3) 反相訊號經amp stage (B) 放大,同時pick up一些noise(B)
4) 之後step 2) output 減 step 3) output
5) 結果係 "輸入訊號 x Gain x 2 + noise(A) - noise(B)"
如果兩個amp stage pick up嘅noise係一樣的的話, noise(A)-noise(B) = zero
目的是noise cancellation.
假設是noise(A) = noise(B)
Drawbacks係線路多左兩個Inverters, 可能多左asymmetric noise同distortion
$445只是一部amp推另一部同樣嘅amp. 冇noise cancellation,只有noise accumulation.
"......用2部串聯推一隻喇叭效果不只升級一倍..."
這句話真係可圈可點
最後修改時間: 2021-12-20 16:04:12 - #447 [hahayanyan], 21-12-20 15:44Haha... 繼續無聊的諗一諗
Such pre amp circuit can be done by jsut 2 12ax7.. seem yes... Haha.. Or whatever any dual triode
紙上談兵發下白日夢都幾快樂
As WCW said... 係要做啲嘢出嚟 先會真正了解
Haha
最後修改時間: 2021-12-20 15:50:01 - #446 [hahayanyan], 21-12-20 15:27# 445
haha interesting ...yes it can be done by such way to connecting them...instead of having mirroring signal path inside one device.. ,but doing that...it is the same concept.... the benefit is slightly better S/N ?
wonder...is it make sense..... as first feeling from my little thought..seem make sense.. of coz..i am 完全是紙上談兵沒有經驗的 ..for such
haha
最後修改時間: 2021-12-20 15:37:10 - #445 [羅密歐], 21-12-20 15:25#443 當然有,連單端後級也可以這樣接。
- #444 [hahayanyan], 21-12-20 15:24# 442
pre amp such as Kenwood L-1000C, FM 255 , ML n0 32.. etc both have kind of truth balance input and single end input stage
phone stage such as EAR 88pb , have single end output as well as transformer driven balance output
delighting to be inspired....
thxxxxxxxxxx
haha
最後修改時間: 2021-12-20 15:26:25 - #443 [hahayanyan], 21-12-20 15:12突然間有個問題 突然之間個腦想起這個東西 想問下你們有經驗的
完全是紙上談兵沒有經驗的
About balance line amp circuit
有冇人用 2 single end circuit from one single end input... 但係一邊用鏡影 inverted signal, one s single end use non invert phase.. And one are inverted phase.. 最後用返一個 differeial circuit.. To get the benefit of noise canceling rejection... Etc.. But not splitting the signal to positive and negative path?
以上嘅問題你哋明唔明
Thx
Haha
最後修改時間: 2021-12-20 15:17:57 - #442 [wcw12], 21-12-20 15:07#438 lalalam兄,請問你有否用過Line Transformer ?
- #441 [wcw12], 21-12-20 15:02gear with balance connection..
Haha兄,有相睇吓嗎? - #440 [wcw12], 21-12-20 14:44Daniel 兄,我自己只是一個用家,我自己最近連示波器也送給朋友了,我不懂的。我貼出來的圖是香港一位退休工程師給我的,他真正專業,更是認真!他退休閒暇研究音頻牛,製造了一些供給幾個像我這樣的發燒友用,我用家而已。
~~~~~~~~~~~~
我把圖貼出來,說明了客觀真實的情況!
数掾好好,那聲音效果才有基礎!
至於好成點?那就是我自己想知道的。那就是要造一些機器出來,自己聽,更提供給人聽,就不再抽像。理論引導實踐求證。
引起了幾個朋友討論,也不錯! - #439 [hahayanyan], 21-12-20 12:55係大部分嘅情況之下如果我玩hi-fi.. 我都係唔鍾意嗰啲平衡乜乜平衡乜乜嘅... 但係好奇怪.. 喺會是有啲器材擺位原因.. 需要用 more than 3 meter interconnection...
不知道是否心理因素.. 總係覺得 其實兩三米開始我已經覺得 RCA.... High frequency 感覺已經完全唔同.. 變差了 for my ear..
喺呢個情況之下我就會用 gear with balance connection... 都可能係心理因素.. Things get back to normal.. 冇咗嗰種變差咗嘅感覺
各種各種嘅體會.. 電子零件嘅 matching... 十分困難嘅事情.. 如果用ture平行線路... If matching.. Etc.. 係一件昂貴及困難...and also not necessary etc..at allll , lost more than gain if there is not much distance between equipments..
因為有以上effective 零件matching 嘅偏見
所以如果要行平衡... 相對 比較 prefer transformer driven device...
合理嘅impedance matching between gear 的重要性... 似乎係 想要好聲嘅重大關鍵
If there is not much of a distance between equipment... Single end all the way seem the best.. For me
總係 覺得 pre amp及唱盤等等東西... 放喺聆聽座位後面有些檔的地方會更好聲, so it invole a more than 3 meter interconnection from pre amp to power amp...
好可能係我個人嘅心理
Haha
最後修改時間: 2021-12-20 13:03:41 - 下一頁 (3 of 25)
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18k初級,更可以作多款直熱三極管滿足負載。
一級傍熱三極管或DHT放大加上單端,真平衡Output, 再配以真平衡牛input 正是我認為理想的設計。
至於好聲與否,可以想像,更可以讓有興趣的朋友親耳品味!!我造了這樣的前級出來,推廣這個理念。