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Lower volume on right side!

DENON 480r amp..at least 10 years old..but over time the right channel is quieter then the left and i have to use the balance control to correct the image .seemed an intermitent fault at first but now its like it all the time!

seems like a common problem with some denon amps bulit around this time. since it seems it was a common problem..is there a common fix for it? dry joint? replace a component?

i would love a new amp but cant afford it! so out with the screwdriver and soldering iron!

Posted by on

  • jayq1971 Feb 12, 2008

    after wiggling a few components to determine which board the dry joint may be on .. i discovered that the large black tower (capacitor?) just before the speaker connections had a dry joint ...a wiggle fixed(!) it.

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I have't seen this porblem, have you tried changing the source place's R with L and see if the sound have change side. If it did then it's your input signal.
I would first check the board for bad solder connection, but it sound like you have a cpu problem or the main ic's procesor. This can be checked with a scope with the ouput of the pre amp to see if the level or the same, with a mono input signal only. You may also have a section of the ouput stage not working, the pre amp , the stage before the main amp out will tell you all by looking at the signal level's.

II know it's not easy, but you will at one point need a scope, without it you will notice you're just going at it blinfowled. When purchasing a scope, put the money it it, a good scope will cost a min of $2k. I'm usind a teck scope and love it, I've also used a leader and find it just the same and sometine better for under $1k.

I hope this help

What About Bob

Posted on Feb 11, 2008

  • robert landry Feb 12, 2008

    Hi Jay.

    Happy you have found the problem, cold solder joint is a commond problem, on older unit's but not all the time, I have found the mainly the output that let go, or power supply problem, just hope this will last another 10 years.



    My system is old, the main source is a sansui receiver model g7700 ( 1973) and the output is source to a dbx3 (1981) , SAE 2800 (1977) to a ashley crosover (2000) to 4 cerwin vega power amp (1972) , M200 for the upper, a1800 for the mi'ds, A 3000 for the lower mid's and m4000 for the sub's, speakers of Martin (1999). The source is records, not the same as cd's and the sound well you can only imagine.

    I keep lot's of parts, schematics, and have found with the time goes by that I need to change job's, no money in it no more, I'm half way there, it's a shame when I here what service people get, and new stuff now can't get parts.

    Keep it for a while I sudjest, there still the best as what they call standard of today.



    REgards



    Bob

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