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回覆 (45): Best of the best. Are we?
Someone duplicate, make or clone this one please. Would be so nice and I sure won't need to tear off the bottom and search for what is really inside! Won't I?  
 
吸唔到! no way la! 一定吸到
bobui
12-05-24
15:10:33
回覆 (44): Best of the best. Are we?
李生  
各级電压是否可标出來?
cpyip
12-05-24
13:28:54
回覆 (43): Best of the best. Are we?
 
 
這是我使用多年的唱頭放大器,是高佬Tim Paravicini的834P。當日售價一萬元,線路古老兼簡陋,就連普通穩壓也欠奉;然而声靚音甜,尤其動態驚人,貴三五倍的機種均望塵莫及。奇怪的是它的燈絲低壓供電,似覺有問題,祇得5V左右。諸位電子音响同道,可有任何高見賜教。  
 
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檢查線路時,發覺次級低壓輸出30V。跟據常規,濾波後應有40V左右。但實際工作情况下,卻只量得31V,何解?  
 
先檢查降壓電阻R16,看有否過荷變值。関機,度阻值,得33 ohm, 正常。再開機,量度壓降,為4V,與燈絲電流0.12 A 吻合。似乎問題不在電阻。  
 
繼而檢察濾波電容。觀其外表,完整無缺。遂関電源,拔走一枝燈胆,再開機,看沒有負載情况之下,究竟若何? 結果,DC 電壓立時彈至41V!意味着電容也是完好無誤。  
 
既然橋式整流、限流電阻、以及濾波電容全部正常,而電路上又再沒有其他元件,何解工作電壓衹得31V?三枝管六條燈絲,每條只分得5V左右,距離標準的6.3V甚遠!  
 
再細看線路,濾波電容耐壓標示40V;而實在銲接上線路板的,更祇有35V。亦即是說,原設計的工作電壓,應在35V之內。如今度得31V,似乎都在預計之中頗正常的表現。  
 
難道是火牛過荷? 整流子過荷? 抑是刻意令其過荷,以達調声之效?又倘若5V燈絲電壓已足以靚爆鏡,我過往為0.2V之差而執著,左穿右搭,弄得焦頭爛額,豈非法國大餐!  
 
附圖該機線路供参詳:  
 
 
limage
12-05-24
12:21:59
回覆 (42): Best of the best. Are we?
Experience shared from a review33 member:  
 
watch out  
_______________________  
上兩個月行開華強北,見便宜買左D黎用,今日一試原來流野,  
銲極都吸唔到錫,用番舊既麥's貨再試試,吸到彭彭聲.....唉,o賴o野!  
_______________________  
 
dkyyu
12-05-24
10:31:55
回覆 (41): Best of the best. Are we?
都係 Thomas 醒! 冇理由 rubycon 扮 master 架? 拆開支 rubycon, 發現原來係 master 就差不多喇o 我都想拆開 D 雞記電容, 裡面原來係 mallory 呀, blackgate 呀, 你話幾開心呢o
Derek2A3
12-05-24
10:08:03
回覆 (40): Best of the best. Are we?
 
 
The one who did it should be very proud of it  
____________________________________  
 
 
對,似乎純為了「晒冷」,根本談不上賺錢。  
 
limage
12-05-24
09:39:01
回覆 (39): Best of the best. Are we?
雞蛋都可以做假,唉!
cpyip
12-05-24
06:21:27
回覆 (38): Best of the best. Are we?
"""""My goodness! A 35V capactior in a 50V can. """"""  
 
 
I have been seeing this cap surfacing from time to time on various forums for not less than ten years. The Rubycon 2200U inside the can might cost 30 cents but such ???Master 6800U shouldn't cost anything more than 1 dollar. I doubt whether it was really a commercial product bought by someone in the market or just another 惡攪 thing made by someone who had too much sense of humour.  
 
I seriously doubt whether the one on the right was same as the intact one on the left before it was torn off. If it really was, I would say the workmanship is super ! The one who did it should be very proud of it. Among all those procedures, could anyone just tell me how to break the original cap and take out its old stuffing without breaking the plastic skin?  
 
I did similar thing recently but what I transplant was four 20U 500V modern caps into a big can (with no skin) for preserving the look of a vintage cap used in a vintage amp. Mine was very much more simplier but yet it took someone like me hours to make one.  
 
ThomasC2
12-05-23
23:16:18
回覆 (37): Best of the best. Are we?
My goodness! A 35V capactior in a 50V can. What is wrong with people  
________________________________________________________________  
 
I see nothing wrong, a properly made branded cap should stand a lightly higher voltage for safety & abuse, say 40V in this case. On the other hand, as a seasoned DIYer, you should only load your components to say max 80% its tolerance to achieve great sound & stability. 50V * 80% = 40V. Perfect match, I couldn't see anything wrong. Oh as the farad, you would be lessoned that 6800 sounds bad (D cap 碌碌都發漲, 搵你愛喇), 2200 is much much better, for sure (零卸易裝又零卸易用).
Derek2A3
12-05-23
20:27:58
回覆 (36): Best of the best. Are we?
My goodness! A 35V capactior in a 50V can. What is wrong with people!  
 
-----  
that's simple. people is looking for free lunch all the time but usually ends with lemons.
drwkng
12-05-23
17:19:25
回覆 (35): Best of the best. Are we?
My goodness! A 35V capactior in a 50V can. What is wrong with people!
bobui
12-05-23
17:10:53
回覆 (34): Best of the best. Are we?
Hi, dear King,  
 
No doubt we are all part of our motherland.  
 
I read from yahoo today:  
 
)(星島日報報道)西班牙報章《新聞三角洲》上周六發表題為「中國豬」的文章,以貶損措詞斥中國移民在西班牙犯下種種「罪行」,指中國人製造冒牌貨攪亂世界經濟、經營中餐館「肥了中國,瘦了西班牙」,文章似乎想把西班牙經濟差的原因怪罪到華人身上。  
 
  該篇文章的作者皮拉爾用了很大篇幅貶損中國移民,包括怒罵中國人製造的冒牌貨已經攪亂世界經濟。他寫:「中國人甚麼東西如眼鏡、皮包、手機等都能仿製,但仿製不到我們高尚的靈魂,如果中國人能把我們的道德也仿製一下,他們就不會成為現在被人指着鼻子罵的對象。」  
 
  皮拉爾還表示,「中國豬」是「要錢不要命」的群體,自從「入侵」西班牙人的領土以來,就借西班牙人的資源累積財富,現在西班牙遍地都是「中國豬」經營的餐館、服裝店,他們把賺來的錢源源不絕地匯往中國,正是「肥了中國,瘦了西班牙」。  
 
  他道:「我把中國人稱為『中國豬』是對他們的敬語。」  
 
  讀者多不贊同  
 
  文章刊出後,許多西班牙讀者不贊同皮拉爾的觀點,認為他言辭過激。有讀者認為,西班牙經濟危機已經病入膏肓,傳媒有意將這些容易引發民眾怨怒的原因引到外國移民身上。他們相信:「為甚麼說『中國豬』而不選擇『拉丁豬』或『東歐豬』,因為他們認為中國人普遍不會採用暴力的報復手段,給中國人欺負一下,不會有危險。」  
 
  另有讀者認為,在經濟危機衝擊下,西班牙不少報紙章的生存空間日益縮小,為擴大發行量獲取廣告收入,一些傳媒刊登帶有辱罵色彩的文章嘩眾取寵,刺激讀者眼球。  
 
dkyyu
12-05-23
16:43:21
回覆 (33): Best of the best?
Hi King,  
 
Yeah, we are all part of it. No doubt our motherland's econony is blooming.  
 
(星島日報報道)西班牙報章《新聞三角洲》上周六發表題為「中國豬」的文章,以貶損措詞斥中國移民在西班牙犯下種種「罪行」,指中國人製造冒牌貨攪亂世界經濟、經營中餐館「肥了中國,瘦了西班牙」,文章似乎想把西班牙經濟差的原因怪罪到華人身上。  
 
  該篇文章的作者皮拉爾用了很大篇幅貶損中國移民,包括怒罵中國人製造的冒牌貨已經攪亂世界經濟。他寫:「中國人甚麼東西如眼鏡、皮包、手機等都能仿製,但仿製不到我們高尚的靈魂,如果中國人能把我們的道德也仿製一下,他們就不會成為現在被人指着鼻子罵的對象。」  
 
  皮拉爾還表示,「中國豬」是「要錢不要命」的群體,自從「入侵」西班牙人的領土以來,就借西班牙人的資源累積財富,現在西班牙遍地都是「中國豬」經營的餐館、服裝店,他們把賺來的錢源源不絕地匯往中國,正是「肥了中國,瘦了西班牙」。  
 
  他道:「我把中國人稱為『中國豬』是對他們的敬語。」  
 
  讀者多不贊同  
 
  文章刊出後,許多西班牙讀者不贊同皮拉爾的觀點,認為他言辭過激。有讀者認為,西班牙經濟危機已經病入膏肓,傳媒有意將這些容易引發民眾怨怒的原因引到外國移民身上。他們相信:「為甚麼說『中國豬』而不選擇『拉丁豬』或『東歐豬』,因為他們認為中國人普遍不會採用暴力的報復手段,給中國人欺負一下,不會有危險。」  
 
  另有讀者認為,在經濟危機衝擊下,西班牙不少報紙章的生存空間日益縮小,為擴大發行量獲取廣告收入,一些傳媒刊登帶有辱罵色彩的文章嘩眾取寵,刺激讀者眼球。  
 
dkyyu
12-05-23
16:40:06
回覆 (32): Best of the best?
Best of the best? You ain't see anything yet.  
--------  
where have you been? i bet the CMC RCA conectors in your yet to come baby are part of that family as well^-^
drwkng
12-05-23
14:50:44
回覆 (31): Best of the best?
Best of the best? You ain't see anything yet.
dkyyu
12-05-23
14:34:44
回覆 (31): Leak........ you boubi!!!
Allow me please! Best of the Best! No la, not the Japanese one. A Lagavulin 1991. No rocks, so nice. Not the most expensive Lagavulin but a hard to find vintage.  
 
"Wish you were here"
bobui
12-05-18
22:51:45
回覆 (30): Leak........ you boubi!!!
Peter, PMC founder in that article had a point! Many good points indeed! But is the cable route long enough to allow the Leak 2075/3090 upper cabinet stand upright? Emmmmmm, please share with your findings, icefox.  
 
Very enjoyable read, right? The old school BBC engineers were so good at their games. Highhands, do get a copy of that article please. It's a very good read.  
 
"Knowledge is Power" lor!
bobui
12-05-16
09:05:06
回覆 (29): Leak........ you boubi!!!
Take a look..... it may offer you some insight on how to tame your 3090 when she returns to where she belongs...... ^__^.  
 
........ shall we try? before you pack her up?  
 
"....... take the top box off and stand it up vertically, it sounds fantastic...... "
icefox
12-05-16
02:22:28
回覆 (28): Middle C
More embarrass when you can't spell lor!
bobui
12-05-13
19:04:52
回覆 (27): Middle C
Another not uncommon term "overtone". I think I should ask my colleagues to create an audio terminology list for me. It starts getting a bit embrass lor!
bobui
12-05-13
19:03:36
回覆 (26): Middle C
 
 
That's because of the overtone.  
 
 
cpsjj
12-05-13
18:45:47
回覆 (25): Middle C
Absolutely!  
 
256Hz is the lowest measure, the highest is 278.4375. All depending on where is the source and calculation method. The strange thing is when I play a tone of the same frequency from a signal generator, it sound so different, so much lower than if compare with a middle C from the upright at home!
bobui
12-05-13
18:35:17
回覆 (24): Middle C
 
 
 
....a piano middle C has a frequency of 256Hz..................my goodness. Its a TRUTH It's a FACT! It's bloody SCIENCE! It's MUSIC  
________________________________________________________________________________  
 
Your pianos are out of tune. They are too "slow". We tune from 440 and the middle C should be 261.6Hz. If you tune according to some European preferences of A=444, then the middle C shall be 264Hz !  
 
 
 
cpsjj
12-05-13
16:55:35
回覆 (23): Middle C
I truely believe that teachers should all wear ugly looking uniform with long pants. No more picking up chalks or notes when dropped. And please don't make me stay behind classes! Its not fair to other students!
bobui
12-05-13
13:39:13
回覆 (22): Middle C
my physics tutor never mention it  
---------  
your physics tutor must be very hot^-^
drwkng
12-05-13
13:23:18
回覆 (21): Middle C
I think I need to go yum cha more. I simply don't have a bloody clue on what hormonic really is. My music teacher never taught me, my physics tutor never mention it. It must be a MI5 level secert only limited to people with names started with a two digit zeros. Mind you, both my music and physics were quickly out of my equation after primary six! Please don't laugh. I think i do have other disciplines lor!  
 
bobui
12-05-13
12:59:24
回覆 (20): Middle C
If we are only talking about the fundamental note, then any speaker with 10k hz should fulfill the task adequately. But, don't forget harmonics extends well beyond that. In fact it's harmonics that provide different tonal signature of different musical instruments.
Derek2A3
12-05-13
12:36:32
回覆 (19): Middle C
Wait minute, wait a second. Violin frequency range goes only to around 10k and if it is true that only a handful of instruments can actually extend the frequency to a little above 10k such as the triangle. Why on earth we must make our audio equipment with a frequency range up to 20k or even higher?  
 
That also remind me of one of the comment Limage enlightened me yesterday about the unnecessary reproduction of a flat frequency curve from 20Hz to 20 kHz.  
 
Even if some of us can hear as well as feel the let say 22kHz revolving around our ear drums, there simply has no instruments in this world that were designed for a nice 22kHz music, right?  
 
Am I day dreaming or someone enlighten me please?
bobui
12-05-13
12:01:51
回覆 (18): Middle C
None of the new findings is going to make my Lowther sound any better or worst but is a very good surprise to learn that most of what we regard as instrumental music is circle around the 250Hz. Surely very applicable to me for most of what I listen is piano music.
bobui
12-05-13
11:37:50
回覆 (17): Middle C
 
From the web, Lowther speakers goes from 40 or 80Hz to 18kHz. So reproducing Chopin Ballade 1 is no problem, but whether it is to a satisfactory level is another matter. IMO it is hard to reproduce the sound of a grand piano truthfully without subwoofer.  
 
kh33
12-05-13
10:59:18
回覆 (16): Middle C
lowther can definitely go lower than that 200. 18khz might be stretching it.  
but what does that got to do with your lowther^-^
drwkng
12-05-13
10:48:15
回覆 (15): Middle C
At yesterday yum cha KH enlightened me by telling me a piano middle C has a frequency of 256Hz. I went to various webs to verify and........my goodness. Its a TRUTH It's a FACT! It's bloody SCIENCE! It's MUSIC!  
 
Man! This got to be the best I have heard for a bloody long time since someone last told me "you are very good looking" which I am pretty sure is MUSIC and SCIENCE to my ears. Despite the many negative comments on Lowther. Lowther is in FACT not only limited to 200Hz to 18kHz. The TRUTH is if I can play Chopin Ballade 1 op.23 faithfully and hearing clearly all the seven and a half or so octaves means that my Lowther can actually go way down below 200 Hz, right?  
 
Am I day dreaming or someone enlighten me please?
bobui
12-05-13
10:05:48
回覆 (14): DIY My Project Mono Phono Pre Amp with vari EQ
My archetype for EQ with steplessly eqalization.  
 
The SCOTT 121 C from 1958.
http://www7.pic-upload.de/04.05.12/jatbhatud7i.jpg
monophonic
12-05-05
02:58:11
回覆 (13): DIY My Project Mono Phono Pre Amp with vari EQ
Micahel,  
 
If possible, you better re-host your photos at another photo service provider like www.photobucket.com . You current photo hosting service provider has a tight rule against hot-linking uploaded pictures from another websites.
icefox
12-05-05
01:51:07
回覆 (12): DIY My Project Mono Phono Pre Amp with vari EQ
I try to show pictures in this thread. When I put in the link address in the URL line only the link address will be shown. What can I do to show the pictures directly under my postings?  
 
Best regards  
Michael
monophonic
12-05-05
01:33:54
回覆 (13): DIY My Project Mono Phono Pre Amp with vari EQ
monophonic
12-05-05
00:25:53
回覆 (12): DIY My Project Mono Phono Pre Amp with vari EQ
 
http://www.pic-upload.de/view-14048703/Wasserlilien.jpg.html  
http://www.pic-upload.de/view-14048703/Wasserlilien.jpg.html
monophonic
12-05-05
00:24:01
回覆 (11): DIY My Project Mono Phono Pre Amp with vari EQ
 
New attempt to show the monopre with another "Look". I call it "golden bells". A bit more vintage.
http://www7.pic-upload.de/04.05.12/l8x1vivj9frf.jpg
monophonic
12-05-04
16:43:21
回覆 (10): DIY My Project Mono Phono Pre Amp with vari EQ
 
Another version of my mono pre with vari EQ.  
Thegolden knobs also from a Gibson Guitar. This kind looks more "VIntage".
[URL=http://www.pic-upload.de/view-14040601/goldenbells_2.jpg.html][IMG]http://www10.pic-upload.de/thumb/03.05.12/2okshpetg5fk.jpg[/IMG][/URL]
monophonic
12-05-04
05:16:14
回覆 (9): DIY My Project Mono Phono Pre Amp with vari EQ
Ja! Natürlich !!  
 
I did German at School in UK, but never got to use it so its almost reduced to weather talk. I get around ok in Germany.  
 
I spent 20 years in UK and now almost the same sort of time in Hong Kong, but I travel to EU regularly and I am in Germany in November. I might attend the ETF in Berlin this year.
daiwok
12-05-02
22:24:32