almost dead densen beat 100

Hi guys,
I have a friend with a big problem...... My friend has buyed an cd player from marantz. Unfortunately the player was working two months and died. The problem is the after the cd has died the amp (densen beat 100) started to behave strangelly.
He asked me what is wrong with the amp (after he asked me if I could look in the amp so if I could repare it maybe). The cd has burned the De Magic from the amp so the amp started to take some strange things at his input. (fortunatelly the amp itself is o.k. - so far as I can determine). The problem is - does anyone knows how could I cut the De Magis from the amp - this is an smd amplifier and it has probably more than one side pcb - I assume that it is two sided. (I would have to take it out from the box to determine that).
Does anyone have some experience with de magic- or some service manual...... I assume that a repare would be expensive because everything is on one pcb and since the pcb is totally burned (at the de magic area) I assume that it would be only possible to replace the whole pcb - expensive.....
here You have few pictures from the amp
 

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I have a fortune that one guy from Densen has decided to help me to solve the problem. So far I have removed R3,R4,R5 and R17 from the Demagic part of the pcb. That disconected the power for the Demagic. The oscilations has stopped.
The problem now is that I have a tiny crackling random noise in the speakers when the amp is turned on. Other than that the amp is working o.k.
The second reply from the guy from Densen said to remove R120 and R220 from the amplifier part of the pcb. That should remove Demagic circuit completely from the amp circuit. I didn't do that yet - since those parts are in the amp section and I want to be 100% sure. Waiting for the confirmation from the man.



By the way - I want to thank the guys from the Densen for their so far help - they didn't need to help at all but they did and I am grateful. Thanks
 
sunrise
I’m glade that you succeeded to repair it with the help of the right place. Densen is great company IMHO. Like I told you, i have barely readable schematic on paper, and I’m unable to transfer it in electronic form…
My version is first one, your model is Mk.3 i think, and here aren’t any resistors with numbers R120, R220.
Good luck!
 

MK APH

Member
2014-12-02 4:41 pm
Hi,
A month ago purchased second hand Densen b-100 and it worked fine until yesterday. First there was there was some mild buzzing sound coming out of right channel, then after turning it off and on again, the amp stopped working. I opened it up, and you can still hear mild buzzing coming out of the transformer, but that supposed to be normal for Densen? Any ideas what should I check first?

Another interesting thing, demagic part of the board was also burned, very similar to the image in the first post. But that probably happened to previous owner, since R3,R4,R5 and R17 resistors and its capacitor were removed.

thank you for any help!