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AUDIOLAB 8000A Modification

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SSWONG 發表於 2007-1-4 17:51:50 | 顯示全部樓層 |閱讀模式
Hi, not sure how many of you here is using Audiolab 8000A. Just some sharing & hope get get some info from those expert here too.

The 8000A i have is with sn 89xxx, issue 4, estimate the product ~1990.
Photo attached is befrore modification.

Modification done:

1) Replace all ecap at pre &power amp & power suply side side to BG std/n

Result --> detail increase a lot, more natural (sound at 1st 15minute is terrible)

2) twisted the cable connect to RCA & also the cable from transformer (slightly cleaner & clearer).


next modification:

3) change 10000uF/50v reservoir to Jensen gold (still waiting the parts)

4) change the EVOX MMK to other pp cap (anybody here got advise for me, if i wish the sound will increase in warm, thick &natural?) pre amp side got 0.47uF x2, 0.33uFx2, 0.047uFx2, 0.033uFx2


Question:

anybody had separate 8000A to pre & power by remove the resistor in R(picture 1)? how's the effect?

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muka 發表於 2007-1-4 23:15:15 | 顯示全部樓層
WINDWSS 兄,

我的8000A推動管偏壓部份seriously burn,所有电阻數值已看不見,底板也烧黑。見到你还有8000A,使我又有一線曙光,可否影幾張close up (底面)给我?看看能不能救回 :
 樓主| SSWONG 發表於 2007-1-5 09:21:17 | 顯示全部樓層
muka,

推動管偏壓英文是?? 是transformer吗?
我对华文电阻名词不太熟悉。。。 ops:
电阻看不清可用multimeter量。
你的8000A是issue4还是issue5?

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muka 發表於 2007-1-5 23:22:14 | 顯示全部樓層
ZTX653和ZTX753組成達靈頓的偏壓。

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muka 發表於 2007-1-5 23:24:20 | 顯示全部樓層
摩机必備線路圖,希望對你有帮助。 :
個人認為張電壓放大級電源斷開,外接regulator會對音質有正面的提升,改DC-SERVO的OPAMP也有帮助。
superwhite 發表於 2007-1-8 01:15:22 | 顯示全部樓層
Hi all,

Can i joint this topic? Because i also using Audiolab, but my is 8000S.  
muka 發表於 2007-1-8 12:51:41 | 顯示全部樓層
[quote:761c5a3b74="superwhite"]Hi all,

Can i joint this topic? Because i also using Audiolab, but my is 8000S.  [/quote]

welcome
 樓主| SSWONG 發表於 2007-1-9 10:46:14 | 顯示全部樓層
Muka,

Have u find out the root cause of the burn?? i will try to take the close up picture today or tomorrow for you!

Is there any good method to increase the audiolab 60w power to ~80w?
 樓主| SSWONG 發表於 2007-1-10 09:19:22 | 顯示全部樓層
muka,

attached 3 photo for u, hope it helps!

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dcastle16 發表於 2007-1-11 13:59:04 | 顯示全部樓層
windwss,

why r u didn't invite me to your new topic? i'm sure will support u one mah since i had owned 8000a and 8000p. i tried to connect my rogers l7t to 8000a its result not really satisfied to me, the datail and sound field are lost, vocal also bright and its noisy. offcaurse i compare with connected 8000p as power amp. So my recommendation is don't use the power amp in 8000a.
i read a review from web 8000a may be is not a good sound as 8000s they recommend to use 8000s or 8000q for pre amp and 8000px or 8000mx2 for power amp. since i am not holding the above models then i might sell it off, that's why i don't plan to mod. them.
i'm looking for 2nd hand 8000s + 8000px or 8000q + 8000mx2, or i will try quad pre and power if i can find.
 樓主| SSWONG 發表於 2007-1-12 09:09:38 | 顯示全部樓層
aharder,

:  : no need invite u also can see the post lah :
of couse 8000A is noisier than use 8000A as pre & 8000p Power...
1) 2 box always have less interference.
2) 60w & 100w is a lot difference too.
3) your 8000P had change all the e-cap to BG, whereas your 8000A is still using old 10yrs old ecap, definitely a lot different. My friend who use the same 8000A version as u who just change 3 cap in power side, he say the noise reduce >30%.
4) the way u use 8000A as pre is not the perfect way, the perfect way is u need to disconnect internally the pre&power in 8000A and use it as pre then only it can really perform as as pre!!! the 8000S had as switch in front panel, whenu press pre, it will disconnect the pre&power inside the 8000s internally... that's the main reason 8000S as a pre is better than 8000A. So u need to manually disconnect the 8000A PRE & POWER by remove the 2pc 560R resistor to get optimum performance as a pre.

my 8000A performance increase >30% after replace ~10pcs BG std even still use 15yrs old reservoir ecap.... if u really 12 compare the performance of 8000A, compare with my 8000A.

give me your email id so that i can pass u some other info on this.



So if u really 12 compare,
 樓主| SSWONG 發表於 2007-1-12 09:28:25 | 顯示全部樓層
pls check the info of separate pre & power of 8000A at the web below!

http://www.hi-fi-insight.com/25/separating-the-pre-and-power-sections-on-an-audiolab-8000a.htm
dcastle16 發表於 2007-1-12 09:52:28 | 顯示全部樓層
windwss,

first, i don't planed to use 8000a for long so i will not do any modification to this amp. secondly, i said 8000s is better then 8000a in the pre side is not because of 8000s had a selector to cut off the internal bridge, it is because of 8000s using the same circuit design with 8000Q which is the highest end pre-amp from audiolab where 8000a using more simple circuit design. ofcaurse the clarity will be better if i change all the ecap to bk but it's still not as good as 8000s. 8000s is really a protential amp if mod. the 2nd hand market price difference from RM 200 to RM 400 only, why not we change it to 8000s (it's come with remote control as well).
this is just my view about audiolab's products. and believe you already had listen to 8000s at superwhite's house, right?   :  :  :  :  :
 樓主| SSWONG 發表於 2007-1-12 11:40:21 | 顯示全部樓層
If that's the case u shall look for 8000Q and not 8000S, if not later u may 12 change again to 8000Q. I'm not as ambitious as u, i'm happy with my 8000A with some modification. with rm400 it is enough for me to change all ecap with BG & big reservoir with jensen.

Since u like remote control so 8000C not suit u... :  :
 樓主| SSWONG 發表於 2007-1-12 11:42:30 | 顯示全部樓層
[quote:8178356bd6="muka"]摩机必備線路圖,希望對你有帮助。 :
個人認為張電壓放大級電源斷開,外接regulator會對音質有正面的提升,改DC-SERVO的OPAMP也有帮助。[/quote]

Muka,

which model of opamp is a good replacement?

my IC is TL072CP (K8728)
dcastle16 發表於 2007-1-12 12:04:26 | 顯示全部樓層
windwss,
you can read this review if can understand mandarin.

Audiolab8000系列功放简介(转自家电论坛)

Audiolab 8000系列的功放可以算是hifi史上的一个小奇迹,并非他的效果有多么超凡入
圣,而在于他的定价和他的声音表现以及近乎“百搭”的能力。

鉴于现在很多朋友对8000系列的功放还不是太了解,我特作了一简要整理,并提供了一下
二手参考价格(最基本的要求:成色都在8成以上,无修摩),希望能对想选择二手8000功
放的朋友有所帮助,不妥之处欢迎批评指正。

论坛的行家、高烧都没有时间顾及交流这些中价器材,我来献丑了

8000系列的合并机:

1、8000LX最便宜,最现代声(声音有点薄,解析力较强,清爽型)。
二手参考价(依成色状态和包装说明的配件情况):2600-3000

2、8000S最贵,使用最方便,有遥控,声音好(前级部分用了独家高级的zq电路,这个电
路只在8000S合并机和8000Q前级上用了,8000Q二手价都在5000以上。)
二手参考价(依成色状态和包装说明的配件情况):3800-4600

3、8000B最实惠,功率大,官方标称75瓦(8000LX、8000A和8000S都是60瓦)
二手参考价(依成色状态和包装说明的配件情况):2800-3400

4、8000A最老,最怀旧(有唱放,素质不错),改良次数最多,由于一直用同样的型号,
所以谁都说不清自己手上的是第几次改良的产品,一般来说灰色的是早期的产品。
二手参考价(依成色状态和包装说明的配件情况):2500-3200

8000系列的后级:

1、8000P最老,100瓦(80年代就推出了)
二手参考价(依成色状态和包装说明的配件情况):3000-3500

2、8000PX最有使用价值和二手购买价值,100瓦(价格比8000P贵一些,但是推出时间较晚
(98年),用料比8000P更精良,解析力强,劲道更足)
二手参考价(依成色状态和包装说明的配件情况):3500-4000

3、8000SX最便宜,60瓦,和8000LX同期推出,是搭配,声音风格和8000LX差不多。
二手参考价(依成色状态和包装说明的配件情况):2500-3000

4、8000M最豪华,125瓦(分体式单声道,要用一对8000M,太贵)
二手参考价(依成色状态和包装说明的配件情况):8000-10000(一对)

5、8000MX最豪华,用料更精良,125瓦(分体式单声道,要用一对8000M,太贵)
二手参考价(依成色状态和包装说明的配件情况):8500-11000(一对)


8000系列的前级:

1、8000C最老(80年代就推出了)
二手参考价(依成色状态和包装说明的配件情况):2800-3500

2、8000Q最经典,也最贵。有遥控,使用方便。
二手参考价(依成色状态和包装说明的配件情况):4500-5500

8000系列二手推荐:

1、经济型合并机:8000B(想玩LP的就只有用8000A了)
2、豪华型合并机:8000S
3、经济型前后级:8000C+8000P
4、中坚型前后级:8000S+8000PX
5、豪华型前后级:8000Q+8000M或8000MX(两台)

还有疑问的朋友,欢迎提问,我尽全力解答,也请8000系列功放的用家和了解的朋友一起
畅谈。
 樓主| SSWONG 發表於 2007-1-12 16:47:59 | 顯示全部樓層
Can give the website of the above article?

his comment acceptable..... but only base on unmodified unit.....

since u not planning to use turntable so 8000s is cost effective for u.... but i may play turntable as well.... : )

when u get your 8000px n want sell 8000p just let us now, maybe we will interested in it!
muka 發表於 2007-1-12 21:11:26 | 顯示全部樓層
[quote:6be95dd348="WINDWSS"][quote:6be95dd348="muka"]摩机必備線路圖,希望對你有帮助。 :
個人認為張電壓放大級電源斷開,外接regulator會對音質有正面的提升,改DC-SERVO的OPAMP也有帮助。[/quote]

Muka,

which model of opamp is a good replacement?

my IC is TL072CP (K8728)[/quote]

平平地,OPA2604也不錯。
我部机断線太严重,都使D饯拿去细陈生處。
audionote 發表於 2007-1-13 03:54:37 | 顯示全部樓層
你們都好頑.
114270 發表於 2007-1-26 01:16:15 | 顯示全部樓層
我剛買進了一台8000LX,後面的speaker插頭好像不是‘香蕉‘的,因插孔的中間部份有東西的,請問應怎辦?謝謝~
 樓主| SSWONG 發表於 2007-1-26 09:30:39 | 顯示全部樓層
not see 8000lx before can show the photo of the back terminal?
muka 發表於 2007-1-26 09:39:42 | 顯示全部樓層
[quote:f94ba31eef="114270"]我剛買進了一台8000LX,後面的speaker插頭好像不是‘香蕉‘的,因插孔的中間部份有東西的,請問應怎辦?謝謝~[/quote]

This is the BFA plug. Some of the AudioLab and also Tag Mclaren (OEM) is using this plug instead of banana
114270 發表於 2007-1-26 12:09:47 | 顯示全部樓層
thanks muka, any adaptor available for 'banana' to 'bfa' plug?
muka 發表於 2007-1-26 21:26:59 | 顯示全部樓層
[quote:cc6f0800f1="114270"]thanks muka, any adaptor available for 'banana' to 'bfa' plug?[/quote]

No need. You can simply go to 鴨寮街 - 和興 buy the plug.
114270 發表於 2007-1-27 02:05:17 | 顯示全部樓層
thank you so much, muka~
 樓主| SSWONG 發表於 2007-2-13 10:23:59 | 顯示全部樓層
Attached photo of my partially modified 8000A for sharing.
1) change e-cap at preamp&power side to BG stnd
2) twisted cable (power supply & to rca)
3) change evok mmk to ero mkt

Result detail/resolution&depth increase a lot, noice reduce, sound stage increase. more natural&musical.

Muka,
need your advice, refer the 3 e-cap (elna RE) circle in green colour in the picture, do u know it is for which circuit? is it for mm/mc or for ???

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muka 發表於 2007-2-13 16:11:34 | 顯示全部樓層
Don't have the machine on hand now but I think it is for the regulator of the phono amp.
 樓主| SSWONG 發表於 2007-2-13 16:32:01 | 顯示全部樓層
i also think like that but i found the 8000S which don't have phono stage also have this 3 ecap (470uf/16v x2, 470uf/35vx1), that's why i'm a bit curious.... if it is not for phono but for the power of 8000A then i may need to change it to better e-cap...

Kindly see the 8000S in picture

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muka 發表於 2007-2-13 16:48:52 | 顯示全部樓層
Let me get back the machine and tracing the circuit board. Update you later.
superwhite 發表於 2007-2-13 20:17:20 | 顯示全部樓層
Hi WINDWSS,

the 8000S pic look like is my AUDIOLAB 8000S leh...... : thanks for advertise my AUDIOLAB     

i have change almost all to BG cap :wink:  will post some PIC later...

Thanks for sharing.
 樓主| SSWONG 發表於 2007-2-14 09:18:12 | 顯示全部樓層
superwhite,

It is your 8000S but picture too blur, next time pls put under bright sun to take a clear photo lah! Go learn with aharder, u see his 8000C photo so clear!
bryan 發表於 2008-8-25 15:19:42 | 顯示全部樓層
hi WINDWSS,

I recently bought an 8000A. I have changed the pair of ELNA 50V 10000uf to Mcap 63V 10000uf only. Is it really worth to replace all cap (especially the pre amp part) to Black Gate? How would you guys compare Black Gate with Mcap? If changing all remaining caps to Black Gate, around how much it would cost (HKD)?

I plan to buy a 2nd hand 8000P too, should I replace all caps too?
 樓主| SSWONG 發表於 2008-8-26 13:12:40 | 顯示全部樓層
Hi! i now only use 8000A as power amp only.

You can replace all the elna cap with blackgate in the pre amp section and the power supply side then you will get a lot more detail which u never heard before it will cost u ~(HKD500).

Anyway after play around with 8000A, i think 8000A has its limitation. So my advice is no need spend so much to mod 8000A, just mod the power supply side enough then go and DIY a tube preamp.

If u plan to get a 8000P then no need to mode 8000A, remove the M cap 10000uf and put in 8000P, then DIY a tube preamp and sell off 8000A.

only have experience on Mundorf film cap and no exp in mundorf E cap.
sugargar 發表於 2008-8-26 23:22:56 | 顯示全部樓層
Hi,

I've Audiolab 8000S also, anyone can post the photos and parts list for modding 8000S please?

Thanks
bryan 發表於 2008-8-27 09:52:20 | 顯示全部樓層
Hi WINDWSS,

Thanks for your advice.

I think solid state amp will be more versatile in all kinds of music. People said that tube amp is strong in vocal but not as detail as solid state amp, is it true?

Do you think 8000Q is much better than the pre amp part of 8000A?

What's the limitation of 8000A you found?
alfcat 發表於 2008-8-27 09:55:22 | 顯示全部樓層
SuperWhite,

No time no see. Which CD player are you using now?

CAT
 樓主| SSWONG 發表於 2008-8-27 17:35:11 | 顯示全部樓層
Dear Bryankeeper,

8000Q definitely better than 8000A peamp section.

If full tube (pre & power) then strong in vocal and most probably you will need to use full range speaker--> those who want strong & fast bass like me may not like it.

So my suggestion is to use tube preamp + solid state power amp --> u will have good & fast bass + little bit of tube feeling. A cheap tube preamp normally has better detail then a lot solid state preamp.

As we all know 8000A always been described as clinical--> compare to most entry level amp it is consider quite detail but it is not warm enough, not musical enough. Yes we can use blackgate to further improve the resolution, musicality and bass of it but it will still sound slightly thin... then we can change the 10000uf cap to jensen (orange/gold) colour--> it become warmer but u will need to sacrify little bit of bass tighness (jensen is warm sound but bass too soft), if u were to use 10000uf blackgate it will cost u a bomb.
For power amp CREEK(using 2 transformer) got a model better than 8000P.

i spend ~hkd 1500-2000 i can DIY a 5687 simple tube preamp which is better than 8000A's pream (better detail, warmer and more natural sound, bass also good when use with solid state power amp)
 樓主| SSWONG 發表於 2008-8-27 17:58:59 | 顯示全部樓層
dear sugargar,

If u really wish to mod 8000S here's something u can try.

A) Change all the e-cap at preamp section & power supply to Blackgate (BG standard is good enough) --> bass will improve a lot, resolution also improve a lot and it become more transparent and musical.

B) twist the internal cable connect poweramp to the connector port for speaker --> improve a bit the imaging & resolution.

C) Change the OPAMP to a better 1.

D)
10000uf capasitor --> low cost is to pararell a 0.47uf/50v blackgate nx-hi-q --> the HF will be much smoother but sound characterisc is still the same

Change 10000uf cap to 10pcs of 1000uF or 5pcs 0f 2200uf cap --> u can select type of sound u want and the bass is definitely better than 1 pcs of 10000uF cap. (this is expensive mod unless u like your 8000S very much if not no need to spend on this)

E) Change the evok film cap especially the 0.1uf in between the 2 pcs og 10000uf e-cap to a better cap --minimum u need to change to ERO MKP1837

F) If u wish to further improve the resolution u can change all the evok (white colour) cap to a better 1 e.g ERO mkp and so on BUT be careful, u can further improve resolution & detail with ERO MKP cap anyway it may sound thin when resolution is too good. Unless your speaker & cdp is sound very thick & warm only u shall think of changing the evok cap to other more detail cap... i do not recommend to replace this evok cap with very expensive cap because it will be better to just DIY a tube preamp by using good cap. (Imaging a simple 5687 tube preamp only need 2 pcs of good film cap) whereas in 8000p THERE ARE >20PCS OF FILM CAP.
 樓主| SSWONG 發表於 2008-8-27 18:06:42 | 顯示全部樓層
this the mod 8000A i done last time(refer picture).

another photo is my DIY pre amp.

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sugargar 發表於 2008-8-27 18:21:34 | 顯示全部樓層
Dear WINDWSS,

Very detail instruction on modding 8000S, looking for those information long time, can start my modding project and thanks a lot.

I have some problem about :

C) Change the OPAMP to a better 1, any good suggestion on which OPAMP I can use (below $500)?

E) Change the evok film cap especially the 0.1uf, any cap (below $300) better than MKP1837?

Not familiar with the those OPAMP and cap model number, need some help.


Sugargar
 樓主| SSWONG 發表於 2008-8-28 10:59:50 | 顯示全部樓層
Dear Sugagar,

If your OPA in 8000S is TL072, u can change it to
a) OPA 2132 (cheap <HKD50), easily to just plug in for replacement, sound similar to OPA627 only little bit different where a bit less musical than 627
b) OPA 627 - EXPENSIVE & u need to use 2 pcs (this is single channel) -

c) AD 825 - single channel, need to use 2 pcs in a special socket(browndog) - ~hkd 50/pc - i'm using this, it has better resolution & detail than OPA627 but not as warm & musical as OP 627.

so it is depend on what characteristic u wan when choose OPA.

For the 0.1uF/100v Evox cap in locate in between the 2 pcs 10000uF big tank, u need to look for some cap which the lead pin is small, size also not too big, if not hard to put it in. A lot good cap is rate with very high voltage and the lead is very big where u can't put them in. The problem of audiolab is that the hole a pcb is very small. maybe u can use evox glass casing film cap or musicap/100v or auricap 0.1uf/100v(u may need to connect thinner lead to musicap & auricap)

P/S: since audio lab pcb hole small, u may use blackgate pk series as it's size smaller than std.
bryan 發表於 2008-8-28 12:57:27 | 顯示全部樓層
Hi WINDWSS,

Thanks for your detail information.

I think I will stick to the 8000A for a while, during the time, I wish I can mod it to the best it can perform (coz limited resources to try other amp... haha...)

To sum up, I should do the following on the 8000A? my 8000A version is "207Bxxxxx"

1) change all the elna cap to BG (pk series) on both pre amp and power part. (PK series is a better grade than the standard one? BG's production is stopped, I can still get it in the market?

2) change the EVOK film cap to ERO MKP for the one between the big tank

3) should I change the OPAMP to OPA 627 as u suggested to sugargar? How much it cost for a single pc of OPA 627?

4) If twisting the wire, should i use silver or copper wire?

Thanks for your help.
 樓主| SSWONG 發表於 2008-8-29 10:22:02 | 顯示全部樓層
Hi, Bryan,

Which country u stay? there are still a lot shop selling blackgate.

or u can buy from this website as well.

http://www.partsconnexion.com/catalog/CapacitorsElectrolytic.html

ur version shld be as photo attached , there is a ribbon cable there. it is similar but with more ecap. just replace e-cap at preamp & power suplly section if u don't use turntable.

pk is small quality as std but with smaller size so more suit/easier to be use in 8000A.

627 got 627AM(most expensive~hkd130?/pcs), 627ap(~hkd70), 627bp(~hkd90) I'm not sure the price now. 627 it is quite musical but the bass is a bit blur for 627ap.
i myself using AD825. FOR 627 &AD825 need to use 2pcs to replace a TL072.
cheap version of 627 is BB OPA2132 (~hkd 50?)


wht cdp & speaker u r using?

No need to change the Cable, just twist them enough by pair, positive & negative as a pair (see my previous picture for the twisting)

another mod can be done is that: change the RCA female connector to a better1 and use silver cable (original is pcb mounted RCA).


With the above mod u can feel a lot different already.... then no point to further upgrade as futher upgrade take more cost and less effect....


for power amp, before you get a 8000P, u shall have a look at creek A52SE(with 2 transformer). It seems better than a 8000P which had moded with BG cap. So 1 of my friend is sell off his 8000P and use creek A52SE with his 8000C preamp.

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bryan 發表於 2008-8-31 18:26:17 | 顯示全部樓層
Hi WINDWSS,

Thanks for your information and u're so helpful.

I'm in Hong Kong and my cdp is "ONIX CD3 SE" and my speakers is "EPOS M12i".

Occasionally I found the left speakers has "click" sound, sometimes it happens when I adjust 8000A's volume knob. I do think the connection to the speakers has no problems. What do you think? Is it the interference inside the 8000A? Can it be fixed?

Thanks
accphoto 發表於 2008-8-31 19:10:59 | 顯示全部樓層
Properly the volume is old and need replacement.
sugargar 發表於 2008-9-1 23:39:09 | 顯示全部樓層
Hi WINDWSS,

I've some photos on my 8000S and need some help:

1) The duel OPA model of my 8000S is L272M RRJXR70B, can it replaced by single OPA 627 x 2 ($150 each)?

2) I've found 2 x Elna 100uf 35V, CE-BP, Cerafine (CE85-9840) capacitors which is red colour, is it polar or non-polar? can I replace it with 2 x blackgate STD 100uf 50V capacitor?

3) I've found capacitor on the board which as the following:
  - 470uf,16V x 4
  - 470uf,35V x 2
  - 100uf,35V x 5
  - 47uf,16V x 2
  - 22uf,35V x 4
  - 10uf,16v x 2
  - 4.7uf,50v x 2
  - 4.7uf,63V x 5

Do I need to replace all of the above capacitor to blackgate std with the same uf? or just replace some important capacitor will be enough?

4) From the photo you can see there is small metal box have word "Audiolab" on it, what parts is inside? is it risk to open it to check what capacitor need to change inside?

Need some advice, Thanks

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 樓主| SSWONG 發表於 2008-9-4 13:52:29 | 顯示全部樓層
dear bryan,

if the noise happen only when touch the volume control then accphoto's suspection is high chance... if it happen when volume control not touch.. a lot possible, if old machine can be contact problem, can be e-cap aging... or grounding contact problem and so on..


dear sugargar,

l272m is different pin sequence from OPA2132 (bur brown type of dual OPA), In the market most convertor of 2 pcs 627 is to convert to pin like 2132 but not LM272M. u may have difficulty to find a correct socket for this.

Best is change all e-cap to BG as 8000S don't have phono stage. but u can leave the 470uf cap alone and change the 100uf & below to BG 1st (if not mistaken all cap at preamp is 100uf n below). i myself only use elna cerafine for the 470uf (to reduce cost)

it is better if u can attached a full picture of your 8000S, it your version is the new china made silver casing version?

circuit in the box is sensitive to RF thus the purpose of the metal case is to provide isolation to reduce interfence inside the box.

when change cap, should use same uf, but voltgae can be same or greater. e.g chnage 4.7/35v to 4.7uf/50v is ok.

check your cap whetehr got arrow/line indicate the neagative pole? see pic ture of BG Std the gold arrow/line indicate neagtive pole. most non polar cap will have non-polar word on the cap n they don't have the arrow/line.

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sugargar 發表於 2008-9-4 14:02:57 | 顯示全部樓層
Dear WINDWSS,

My 8000s is the new china made silver casing version, maybe I will just replace those cap under 100uf to BG std 1st and skip the OPA.

Thanks for your advice

Sugargar
sugargar 發表於 2008-9-4 23:46:21 | 顯示全部樓層
Dear WINDWSS,

I've re-checked my 8000S and got 3 photos of my OPA, Elna 100uf red cap and whole PCBboard.

I fouund the OPA is A2134PA, can I replace it with OPA627 x 2? or LM4562NA, any better OPA can be used?

I can't find any -ve sign or (N) word on the 100uf 35V Elna Cerafine Red colour Capacitor and I've measured the diameter of the cap is 16mm . Do you think it is non-polar cap?

Need some help, Thanks

Sugargar

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 樓主| SSWONG 發表於 2008-9-5 14:46:58 | 顯示全部樓層
dear sugargar,

OPA2134 can be repalced by 2pcs OPA627 (opa627AM=metal case is the best)

understand Elna silmic CE-BP is bi-boplar (non polarization), so if u can find the negative mark then this cerafine BP is high posible is bi-polar type too.. i understand from elna their BD version alos bi-polar -->B normally stand for bi-polar...
so to play save u can use BG N series for replacement of this 100uf cap.
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