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BM 4400 Mexico

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BeoHut
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BeoHut replied on Fri, Mar 29 2013 11:09 PM

Congratulations Søren! Well done!

I am following this thread from the beginning. A complete overhaul, sometimes too technical for me, but worth reading.

Glad you did it with all the technical help of the other BeoW here on this forum!

Enjoy it, take a cuba cigar, a whisky and listen to your BM4400!  

I hope more pics will follow and see the BM in its full glory!

BO
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BO replied on Sat, Mar 30 2013 12:14 AM
Congratulations!😄

//Bo.
A long list...

sonavor
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sonavor replied on Sat, Mar 30 2013 2:11 AM

That is awesome Søren.  Way to stick with it. 

-sonavor

Piaf
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Piaf replied on Sat, Mar 30 2013 5:47 AM

Bravo Søren!

You did it, you actually did it! Lets have a Party !!!

 

I know that I can safely speak for virtually everyone here at BeoWorld who has followed your incredible adventure….. we are so very PROUD of you, your determination, tenacity, and steady attention to detail.

 

And thank you for the most generous commentary….. I am delighted that I was able to help keep your spirits up.

 

This is a victory like few others! Congratulations! Big Smile

 

Jeff

Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Bogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 5000 T4716, Beocord 8004, Beocord 9000. Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century,  S-45, S-75, S-75, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase,  B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder

 

tamtapir
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tamtapir replied on Sat, Mar 30 2013 7:48 AM

I am so glad for your success, Søren. This has been a real thriller, but like all good stories it ended happily.

/***

chartz
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chartz replied on Sat, Mar 30 2013 8:13 AM

It does always come to that, doesn't it, silly little things.

The other day I was working with a pupil and told him to check a PCB because the kit was not working. Visually, nothing was wrong and all the correct components were at their correct places. I told him to check the tracks with an ohmmeter and bingo! a track was broken just at the soldering point of a resistor and it was invisible, even magnified under the thread counter...

So yes Søren, familiar story, and above all: WELL DONE MY FRIEND!

 

Jacques

Peter the Biker
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My congratulations too for your resurrected easter egg.

Peter the biker

valve1
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valve1 replied on Sat, Mar 30 2013 9:59 AM

Good one Soren !

I admire your persistence. Get your bv1600's hooked up and have a day off :-)

Dillen
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Dillen replied on Sat, Mar 30 2013 10:26 AM

Yes - thumbs up

Martin

Peter
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Peter replied on Sat, Mar 30 2013 11:05 AM

Many congratulations - you really have put a huge amount of effort into this and I am sure you will now enjoy what must be one of the best 4400s in the world! I am deeply impressed.

Peter

DMacri
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DMacri replied on Sat, Mar 30 2013 1:58 PM
Congratulations and well done!

Dom

BeoSystem 5000, BeoSystem 6500, AV 7000, BeoSound 4000, Playmaker, BeoLab 2500, BeoVox S-45, BeoVox S-45.2, RL-140, CX-50, C-75, CX-100, 3 MCL82 link rooms, A8 earphones, A3, 4001 relay, H3, H6, and ambio 

Rich
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Rich replied on Sat, Mar 30 2013 7:38 PM

Congratulations on a job well done.  Look to the east at 7:00 pm EDT - there will be a toast to you from Florida.

Blah blah blah, blah blah ba ran

Søren Mexico
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Will pick up my true old magnetic compass and face 80-85°, in my left hand a well mixed Rum and coke, and will say out loud: "SKÅL Rich". at the same time listening to BM 4400 connected to P45s, playing from CD Bruce Springsteen, No Surrender.

Collecting Vintage B&O is not a hobby, its a lifestyle.

Piaf
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Piaf replied on Sun, Mar 31 2013 4:06 AM

So Søren, now that you have your Beomaster 4400 brought back from the brink, as it were an electronic Phoenix and now performing brilliantly, can you not say that it is absolutely beautiful?

 

I can only imagine your pride on what you created from such a dubious candidate for restoration, yet you did it.

 

Have another rum and Coke® and tell us how you feel about your 4400 and please let us know how it SOUNDS!

 

Not to compete in any way with Rich, but I am currently drinking a toast to you and your Beomaster 4400 from beautiful British Columbia. True it is cheap white wine, (budget restraints being what they are, but it is the thought that counts!) Drinks

 

I celebrate your victory with you my friend!

 

Jeff

Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Bogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 5000 T4716, Beocord 8004, Beocord 9000. Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century,  S-45, S-75, S-75, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase,  B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder

 

RaMaBo
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RaMaBo replied on Sun, Mar 31 2013 12:46 PM

Congratulations Søren!

you finally succeeded in finding the fault after the great work you did before restoring the BM4400.

Enjoy your great work!


Ralph-Marcus

 

Ralph-Marcus

Duncan Jones
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Un-bloody-believable.....I have been watching with great interest from Australia. At one stage I thought you were going to outshine even the great Icelandic sagas with your BM4400 story.

Well done, and congratulations. I'm about to launch into recapping a BM8000.....now if only I could work out what to do with this oscilloscope....Confused

Søren Mexico
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RaMaBo:

Congratulations Søren!

you finally succeeded in finding the fault after the great work you did before restoring the BM4400.

Enjoy your great work!


Ralph-Marcus

 

Ralph, a big thanks to you, your advices and help, kept me going, and I learned a lot from this journey, it will keep my BeoVirus alive and blooming, and I had a lot of fun doing it. I´m still wondering why a small failure like this, can have such an impact on a circuit, and I am studying the schematics to try to understand it.

BTW, the BM was playing 4 hours yesterday, connected to P45, Bvox 1600 and BG 1202, playing FM and some LPs.

 

Collecting Vintage B&O is not a hobby, its a lifestyle.

Magnus
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Magnus replied on Sun, Mar 31 2013 6:36 PM
Hello Soren, and congratulations from Sweden!

I have followed your hard work with the BM 4400, and I'm very impressed!

(So much that i had to salute with a good danish beer (and Gammeldansk)).

/Magnus
Steffen
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Steffen replied on Mon, Apr 1 2013 1:21 AM

Congratulations Søren Cake

I haven't had much time lately to check out Beoworld. But I just to had to see how you were doing with your 4400 project.

I'm really glad to see that you have solved the problem and brought this wonderfull classic receiver back to life...Well done Yes - thumbs up

I will also salute with a good Danish beer (Easter Brew) Beer

Piaf
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Piaf replied on Mon, Apr 1 2013 4:16 AM

With all these international toasts and salutes I think the world’s breweries, wineries, and lacquer concerns must have had to put on an extra shift! And they owe it all to Søren and his magnificent achievement. Lets have a Party !!!

 

Jeff

Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Bogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 5000 T4716, Beocord 8004, Beocord 9000. Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century,  S-45, S-75, S-75, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase,  B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder

 

Søren Mexico
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Well, we all enjoy life, and a good cold beer, a nice glass of vine or a well mixed drink, is part of the joy, as is listening to good music from a good playing vintage B&O amp. Combined with selecting an LP that fits to your mood, thats when life is perfect.

Here she is playing Grieg, The Morning, in the morning light coming through the window. On this occasion a strong cup of Java was the drink.

Collecting Vintage B&O is not a hobby, its a lifestyle.

Piaf
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Piaf replied on Tue, Apr 2 2013 3:37 AM

Hello Søren,

 

What a very handsome instrument you have CREATED! You sound almost like the proud father of their first-born child! (You really do!)

 

So now that you have this superb Beomaster 4400 receiver may I humbly suggest a proper turntable for your next project?

 

I know when I am in the mood for concert that sounds like the real deal I always go for my favourite B&O possession, the Beogram 4000. Now finding one of these gems might be a bit difficult, but not so a Beogram 4002 or 4004, either would be a wonderful addition to your collection.

 

Failing that either a Beogram 8000 or the “zenith” of the line, a Beogram 8002. (I have all five and love them all.)

 

Trust me on this, any of these choices would add a great deal to your listening pleasure AND I guarantee you that repairing any of them would be a walk in the park after your resurrection of your Beomaster 4400!

 

Give it some thought.

 

Jeff

Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Bogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 5000 T4716, Beocord 8004, Beocord 9000. Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century,  S-45, S-75, S-75, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase,  B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder

 

Søren Mexico
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I AM proud, its the first big job I have done in BMs, but as for the BGs, lets go here.

Collecting Vintage B&O is not a hobby, its a lifestyle.

Friedmett
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WOW!

Congratz is in indeed in order. This thread has been an exiting leason on persistance and it is wonderfull to finally log on to find that you have reached your personal goal with this BM4400.

Way to go Søren!

Piaf
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Piaf replied on Tue, Apr 2 2013 4:07 PM

Ah Søren,

 

I see that you are way ahead of me, as usual. Embarrassed

 

Jeff

Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Bogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 5000 T4716, Beocord 8004, Beocord 9000. Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century,  S-45, S-75, S-75, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase,  B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder

 

John Francis
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Hello Soren,

Like so many others I have read each and everyone of your posts. It has been a difficult journey I know for someone so humble as you but a rewarding one. I have been lost many times regarding the technical aspects but have been fascinated none the less. What we all an learn from what you have done is that it is the simple things like broken traces that can make a difference in when something works and when it doesn't and not something more sophisticated like a bad component. Thank you! Also out of curiosity what do you use to clan the component board with?

John

Søren Mexico
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jfrancis:
Also out of curiosity what do you use to clan the component board with?

Thanks John, I normally use mineral spirit for the PCBs, but this one was so dirty that I had to use isopropyl alcohol, after soldering I use mineral spirit.

Isopropyl alcohol will clean off the print on the solder side if left too long on it.

Collecting Vintage B&O is not a hobby, its a lifestyle.

Piaf
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Piaf replied on Wed, Apr 3 2013 1:50 AM

Søren (since you have arguably the “best” condition 4400 around) and anyone else who cares to comment, I have two Beomaster 4400 questions and would very much appreciate knowledgeable impute.

 

  1. Would you describe the 4400 as a well balanced amplifier favoring neither treble nor bass?
  2. Does the PHONO switch remain engaged (depressed) when selecting TAPE 1? And is there any reason other than a switch malfunction for this possible situation?

 

Thank you for your enlightenment and enjoy your 4400.

 

Jeff

Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Bogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 5000 T4716, Beocord 8004, Beocord 9000. Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century,  S-45, S-75, S-75, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase,  B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder

 

Søren Mexico
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1. I have only been listening to the BM 4400 for some 10- 15 hours, but yes I think it is very "neutral" with all tone controls in "0", my BM 2400 sound "different" (not bad).I think I will have to listen to it for some more hours, before everything is "burned inn". At the moment I dont listen for quality but for failures, checking for temp and funny sounds, kind of nervous listening mode.Laughing

Tape1 engaged at the same time as FMs or Phono is correct, for monitoring recording sound going to Tape, depressing FM or Phono one more time will disengage Tape1.

Collecting Vintage B&O is not a hobby, its a lifestyle.

Piaf
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Piaf replied on Wed, Apr 3 2013 3:44 AM

Hello Søren,

 

Many, many thanks for your response, which was exceedingly helpful. Yes - thumbs up

 

Part of me shutters at your term “burned-in” but I guess that is the accurate way to describe your amplifier.

 

While I understand your “nervous” listening for faults, you really should realize that what you have is essentially a new vintage amplifier which is most unlikely to disappoint.

 

All new parts, ridiculously careful testing all point to years of trouble free operation and enjoyment. Big Smile

 

Jeff

Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Bogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 5000 T4716, Beocord 8004, Beocord 9000. Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century,  S-45, S-75, S-75, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase,  B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder

 

Søren Mexico
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Today I was very brave I turned the volume up to 6, (very loudLaughing), P45s connected, burning in, is maybe a bad description, but as a with new car you have a running in period, where you go soft with it. I like to do the same with my electronics. Except for my coffee brewers, they have make strong coffee from the first day.Big Smile

Collecting Vintage B&O is not a hobby, its a lifestyle.

DMacri
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DMacri replied on Wed, Apr 3 2013 11:56 AM
My understanding of the burn-in process is to "form" the capacitors. They need the application of working voltage and current flow to settle in to their final characteristics. The resistors, diodes and transistors don't really need to burn in because their characteristics are not affected by their "surroundings" in the same way.

Dom

BeoSystem 5000, BeoSystem 6500, AV 7000, BeoSound 4000, Playmaker, BeoLab 2500, BeoVox S-45, BeoVox S-45.2, RL-140, CX-50, C-75, CX-100, 3 MCL82 link rooms, A8 earphones, A3, 4001 relay, H3, H6, and ambio 

Orava
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Orava replied on Wed, Apr 3 2013 12:31 PM

There is also higer failure rate at begining of component use, or should we say, if it is going to break, it breaks early rather that mid-aged.

So a little stress is ok imo.

 blah-blah and photographs as needed

Piaf
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Piaf replied on Wed, Apr 3 2013 4:06 PM

This is beyond interesting and highly educational. How long (usually) does this burn-in process take?

 

Jeff

Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Bogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 5000 T4716, Beocord 8004, Beocord 9000. Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century,  S-45, S-75, S-75, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase,  B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder

 

DMacri
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DMacri replied on Thu, Apr 4 2013 2:07 AM
Orava is on to something. Most electronic devices will fail in the first 30 days, or will probably last for more than 15 years of steady use. The burn in time probably varies by component and circuit. I'm not sure I can come up with a definitive answer for that.

Dom

BeoSystem 5000, BeoSystem 6500, AV 7000, BeoSound 4000, Playmaker, BeoLab 2500, BeoVox S-45, BeoVox S-45.2, RL-140, CX-50, C-75, CX-100, 3 MCL82 link rooms, A8 earphones, A3, 4001 relay, H3, H6, and ambio 

Piaf
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Piaf replied on Thu, Apr 4 2013 2:48 AM

DMacri:
Orava is on to something. Most electronic devices will fail in the first 30 days, or will probably last for more than 15 years of steady use. The burn in time probably varies by component and circuit. I'm not sure I can come up with a definitive answer for that.

In the case of capacitors is it theoretically possible for them to go though wild changes before settling down?

Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Bogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 5000 T4716, Beocord 8004, Beocord 9000. Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century,  S-45, S-75, S-75, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase,  B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder

 

Orava
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Orava replied on Thu, Apr 4 2013 7:12 AM

Piaf:

In the case of capacitors is it theoretically possible for them to go though wild changes before settling down?

I dont think it is possible, because if they do that, it might cause seriuos problems elsewhere in circuitity.

I do "burn in" mainly to see if semiconductors ( or even solderingpoints) will make troubles or not. And if they do, it will happen quite soon.

 blah-blah and photographs as needed

tournedos
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Piaf:
In the case of capacitors is it theoretically possible for them to go though wild changes before settling down?

No. If they did, nothing coming off the factory assembly line would ever work.

Personally I don't believe in this. It will probably take 0.01 seconds for a factory new electrolytic capacitor to work up to spec after first power on. That is not to say that something couldn't slighly alter (apart from normal aging), but when mysticians extend this to completely dry & inert components such as film capacitors, resistors of for heaven forbid power cables, it all gets just silly.

The "bath tub" style failure rate graph, on the other hand, is well known from reliability theory so it is always a good idea to test drive a new assembly for a while before declaring it works. Modern mass production doesn't have time for this, thus the high early failure & DOA rate of consumer electronics.

EDIT: forgot to say: well done Søren! Yes - thumbs up

--mika

Peter
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Peter replied on Thu, Apr 4 2013 8:06 AM

I agree completely - I don't believe in burn in but I do believe in testing newly added components and repairs carefully to make sure they are working properly. If this counts as burn in, I am all for it! I don't think components need to be run in like a car though!

Peter

DMacri
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DMacri replied on Thu, Apr 4 2013 11:27 AM
It's probably just because I spent a lot of time restoring tube audio equipment, but I got in the habit of using a variac to slowly form the main power supply caps. Here's an excerpt from Anglefire.com:

... the insulator is a thin layer of aluminum oxide. One of the plates of the cap is the aluminum foil and the other is a layer of porous paper impregnated with something not unlike battery acid. The layer of oxide is formed by applying a voltage when the cap is manufactured. The layer is re enforced every time the capacitor is used. Long periods of disuse can, and usually do, cause most of the oxide layer to break down.

The thinner this layer gets the less voltage it will stand without conducting current. A very old 450 volt capacitor, NIB or in an amplifier, may only test to 50 volts. It needs to be reformed before attempting to use it.

Reforming means to regenerate the oxide layer. This is done by increasing the voltage until current begins to flow. This is not a normal condition for a capacitor. The trick is not to run too much current through it. It the current is allowed to get too high one of two things can happen and they are both bad. The capacitor can get so hot that the water turns to steam, boils. The build up of pressure can cause the capacitor to literally explode with a BANG! In the other case the oxide arcs through and the intense heat of the arc burns the paper turning some of it to carbon. That's a conductor and its presents places a permanent short across the capacitor.

Dom

BeoSystem 5000, BeoSystem 6500, AV 7000, BeoSound 4000, Playmaker, BeoLab 2500, BeoVox S-45, BeoVox S-45.2, RL-140, CX-50, C-75, CX-100, 3 MCL82 link rooms, A8 earphones, A3, 4001 relay, H3, H6, and ambio 

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