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Bogenj MX60

Discussion in 'Shock Brother's DIY Amps' started by jh45gun, May 3, 2009.

  1. jh45gun

    jh45gun Banned

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    Today for grins I plugged into my Bogen Mx60 and played for a bit and man this thing really snorts but then at 60 watts I guess I would expect that. Now I replaced the two (C3 &4)40 MFD caps that are for the 530 VDC supply that the Center tap of the OT goes to. Next to be replaced would be the cap that uses 20 MFD (CI) that is for the 440 DCV feed that goes to the output tubes.Next would be the cap can C2 three cap can (ABC) that would be for the phase inverter area, The output tubes and the AF amp after the master gain. Now I suspect I will just use individual caps instead of replaceing the 3 cap can as I can get them from my tech. Amp sounds really good as is but I know that replaceing at least these electrolytics is probably the right thing to do. There is several other caps that are electrolytics too that are smaller values and less voltage for other circuits I may leave for now. I figure at least get the main filter caps done.
     
  2. jh45gun

    jh45gun Banned

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    Just wondering since I read this post about the champs and heard what they said about the caps. http://www.tdpri.com/forum/amp-cent...verface-champ-guts-does-she-need-cap-job.html

    Like I said I replaced the two 40 MFD caps that were cardboard tubes as they looked their age and the amp does sound better for it. These caps fed the highest voltage circuit in the amp. The next caps that I considered replaceing is a electrolytic and a 3 cap can as this amp being a PA head has more caps for filtering than the average guitar head. It also has three rectifier tubes. Now since I replaced them cardboard tube 40 mfd caps the amp really does sound good so can I get by for a while with out replaceing the other caps. Being what this amp is and it I am sure sat for a while it also was used heavy in its lifetime I would suspect being a school or church PA. It also has had some tube changes as I said ealier so it has had some one do some stuff to it. They must have felt the caps were ok. Comments????
     
  3. bdgregory

    bdgregory Tele-Afflicted

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    I'm far from an authority on this but all caps deteriorate with age, and eventually fail. This is tru especially of the electrolytics (ie the big can triple cap and the 40uF caps). If it sounds ok for now you can use it fine, but assuming they are original caps you're running on borrowed time. On the vintage amps I've rebuilt, I replace all caps as soon as possible, with possible exception of some of the small mica caps that aren't in the signal path.
     
  4. jh45gun

    jh45gun Banned

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    Yea I suspect the best would be to change them out at least the higher voltage ones. maybe the others later as there is besides that 3 cap can a 4 cap can that is 5 mfd each at 200 VDC and two individual 20 mfd one at 500 VDC and one at 250 mfd. two individual 30 mfd at 150 vdc and a 100 mfd at 3 vdc.
     
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