Mike Lindsey Posted June 21, 2001 Share Posted June 21, 2001 I have a Yamaha M-4 amp (125 w/ch) that I bought new in 1982. This amp has powered my Infinity Column II's from 1982 to 1995, and now my Klipsch CF-2's since then. The problem is that over time, it's taking longer and longer for the amp to turn itself on. Over the last 5 years or so, it has gone from 5 seconds to now 45 minutes to have power. I'm really stumped as to what's going on. I have since ordered a Denon 4800 for my new HT room but would really like to set this amp up in my bedroom for 2 channel stereo. My local Sound Advice said they would fix it (I'm sure they send it out somewhere) for a flat fee of $150, which includes parts. Does anybody have any idea what might be the problem with this or should I just send it in to get fixed? Thanks in advance, Mike Quote Link to comment Share on other sites More sharing options...
Spider124 Posted June 21, 2001 Share Posted June 21, 2001 I suppose it could be two things: 1) The Power Supply caps are bad. The amp might wait until the rails reach a certain level & is stable before turning on. If the PS caps are bad (the amp is 19 years old, after all). Replacing them with new Panasonic, Mallory, or Sprague types should work. 2) There is a fixed-delay circuit which is broken. This probably goes back to a different capacitor being broken, but there is really no way to know which one. There is probably no real 'quick fix', and it is very dangerous to fiddle with power amps, so if you don't have lots of electronics experience, better take it somewhere. Charlie ------------------ "What's that noise?" "It's the carpet, it kinda mutes the speakers." "No, it sounded more like the chandalier falling." Quote Link to comment Share on other sites More sharing options...
maxg Posted June 22, 2001 Share Posted June 22, 2001 You could always leave it on continuously. I never switch off my amps. Quote Link to comment Share on other sites More sharing options...
djk Posted June 22, 2001 Share Posted June 22, 2001 >>2) There is a fixed-delay circuit which is broken. This probably goes back to a different capacitor being broken, but there is really no way to know which one.<< Dried out capacitor in the relay turn on delay circuit is causing the problem.A $1 part and a 10 minute fix.Order service manual from Yamaha(about $8).Send it to me.I'll mark which parts to replace and return it to you.You could buy a cheap soldering iron and do yourself.Or take the marked manual and the part to a TV shop and pay them $10~$20 to do it for you. Quote Link to comment Share on other sites More sharing options...
Mike Lindsey Posted June 22, 2001 Author Share Posted June 22, 2001 Wow! You guys are great! I really like your idea, Max. DJK - I will order the manual today and send it to you as soon as it comes in. If you would Email me at mlindsey@dewberry.net and forward your address, I would greatly appreciate it. I do have a soldering iron, so will attempt to do the work myself. Thanks again, Mike quote: Originally posted by djk: >>2) There is a fixed-delay circuit which is broken. This probably goes back to a different capacitor being broken, but there is really no way to know which one.<< Dried out capacitor in the relay turn on delay circuit is causing the problem.A $1 part and a 10 minute fix.Order service manual from Yamaha(about $8).Send it to me.I'll mark which parts to replace and return it to you.You could buy a cheap soldering iron and do yourself.Or take the marked manual and the part to a TV shop and pay them $10~$20 to do it for you. Quote Link to comment Share on other sites More sharing options...
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