ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Wally & I are new to BeoWorld. He acquired a BM4400 with BeoGram1001 and BeoVox S75 speakers from a friend, were in a cupboard not working for years (the system, not the friend). We want to resuscitate the system with the help of all of you. The BeoGram showed signs of dismantling but the BM4400 doesn't. Beogram not fully restored so can't use as input. Here's a picture of the BM4400 and S/N.
The BM4400 looked OK inside, cleaned dust off with clean brush and blower. Some of the power cables near the transformer and 2 big capacitors were quite 'sweaty'. No sign of burned components, damage or previous repair work. After much effort and study of circuit diagram in the manual we were able to locate many of the Test Points. Voltages on all of those we could find were within the error range of our small multimeter. 35V on diagram measured 39V. Points 6, 11, 12, 13 in table on page 5-5 measured as specified +/- 2 or 3V.
Here's what happens. When switched on and FM or Phono switch depressed, a loud, 'fat' click comes from the speakers and the 'overload' light comes on. When switched off, the loud click happens again. While on FM, the system can be tuned accurately to one of our local stations using the two left-right red tuning lights but no sound comes out at all, even on max volume.
Where should we look for a fault? Neither of us are electronic people but can get around with the components, so not too technical please!
The overload light and the fat loud sound shows to a failure in the output stages, no sound at all the same, the sweating capacitors shows you it is time to change all the electrolytic caps. Normally in these nice amps it is recommendable to change caps,trimmers, rectifiers and lamps. In yours I would think you also have to go after the output transistors. I have one here playing since nearly a year after an extensive repair/overhaul. Look here
Its a very long thread, but it will help you getting to know your BM 4400,
The BG 1001 will need a new belt and a very good cleaning and lubricating, here is what I did to my 1202
Collecting Vintage B&O is not a hobby, its a lifestyle.
Yes, Søren's guidelines are very useful, as always.
I also did a Beomaster 4400, see here. The output transistors were just fine in my case. I still have a few parts should you require one.
The fact that tuning still works is because the failure only cuts the output stages power, so the preamp and tuner remain powered.
And welcome to Beoworld!
Jacques
No further work done or new information, but we really appreciate the advice given.
Just for completeness, I want to add a few images of the system we're working on now that I know how to do it correctly.
Here's the BeoMaster 4400. The case and switches are in pretty good condition, only the cover for the presets is missing, but this seems a common problem, and I've seen the various ways the cover can be fabricated.
Here's the BeoGram 1001:
And lastly here are the speakers:
So now to digest the advice and take some action!
Wally and I first posted details of his BeoMaster 4400, with turntable and speakers, on the WorkBench Forum on 7 and 14 January 2014 under the heading "BeoMaster 4400 no audio. Help!"
We worked for months to the best of our limited ability on his Beomaster 4400. We took the upper casing off with a little difficulty, then separated the inner PC boards. After much study of the Manual we got to be able confidently to identify the electronic components. The last action was to identify the test points before trying to do some tests. We got part way through this. The few test points we actually took readings on showed correct values. But we didn't get far. I was able to determine that the main voltage of about 35 V was being carried through to all the places it was supposed to. We got to the point that we were ready to carry out the recommendation to replace all the electrolytic caps.
Our attention was diverted by another activity and after many months we had a discussion on the future of our Beomaster effort. We decided that we were not ever going to be able to work at the component level with the few skills and tools we had at our disposal. This was quite a sad decision for us both. We had so looked forward to getting the set going again.
So we have abandoned our project!
But now we have the following question: is there anyone in South Africa who has the same passion for the B & O vintage kit shown by all the 'Workbench' Forum members and the Vintage Products followers, sufficient to want to continue Wally and my efforts. I think Wally would be very happy to see his B & O being disposed of to someone who has the skill and desire to refurbish it. Would anyone interested please communicate with me at alinde17@gmail.com.
International users would also be welcome but possibly the shipping costs would be pretty high.
Its a shame you had to give up on what is one of my favourite amps the 4400. It has a great sound.
BenSA is the only Beoworld member I know in S Africa, perhaps there are others ?
Anyone heard from BenSA recently ?
Hi Alec,
Yes, it is a shame you had to give up on your Beomaster 4400 (I have one too) but I gotta tell you; amplifier rebuilding is a BIG job left mainly for professionals with Søren de Mexico being the rare exception. (Søren is an electronic maven supreme.)
I attempted to repair my Beogram 8000 with Martin’s capacitor kit, but the aged caps were the least of my 8000’s problems with over 100 solder points needed and God knows what else?
I also tried recapping my MC120.2 speakers resulting in dramatically little effect, if any.
So when my Beomaster 4500 and Beomaster 2400 needed rebuilding I asked Martin if he thought I might be able to handle this and Martin was the picture of politeness in saying not really. And I am sure Martin was right.
B&O amplifiers built in the seventies and eighties have reached an age where they need a good many parts replaced and everything, but everything needs to be tested to see if the values match the specs. (That lets me out right there.)
I hope you find a suitable home for your lovely equipment, but if you change your mind and can not find a proper repair facility in South Africa, I have a fantastic shop near Atlanta, Georgia that rebuilt both my 2400 and 4500. Of course the shipping will be a killer.
That said if money were of no concern and you could overlook the horrendous shipping costs to Denmark; Martin Olsen is likely the best place to send your 4400.
All the best!
Jeff
Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Beogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 4500, Beocord 5000 T4716, Beocord 5000 T4716, 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-45.2, S-45.2, S-75, S-75, M-75, M-100, 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
Yep, the 4400 is a really great receiver and although fixing it can be a time-consuming affair, it sounds so good that it is entirely worth the while. We listen to ours every day, feeding M70s. They are happy with all sorts of music.
Well, there you go!
I grew up in, and learnt my electronic skills in Johannesburg.
If I could, I would have been happy to help you.
My first B&O equipment (BM1400, BG1000) was stolen in 1978 from our home in Jhb.
Never saw them again....
Menahem