Originally Posted by Rpml
I am kind of surprised after all those problems you would still go with another denon. On this page alone 3-4 people posted problems they have had.. I think i am a bit wary of them after my 3805 and now the DOA 4520.. going to start looking at other brands today.
This sort of thing is normal for any electronics. No affordable consumer electronics are 100% tested. QC processes generally involve testing of a representative sample, usually per lot. The rule I have lived by for several decades is, electronics either are DOA, work for less than a month or work virtually forever. Generalizing of course. In recent years I have had to adjust the last option to "until obsolete".
Originally Posted by PeterK
Not sure why there have been the recent posts on faulty 4520s. I have been an owner for almost a year now and have read this entire thread. The people with issues up until the last month have been very few. Just wonder how many of these end of season shipments from BB are actually repackaged and resealed units for there to be so many problems?
Mine had to have been in a new box with a new or unused Audyssey mic if this were the case.
Originally Posted by chi_guy50
FWIW, I just got an X5200 and it was DOA; I'm currently waiting on a replacement unit.
There is nothing inherently errant in either the 4520 or X5200 that I know of; but the nature of consumer electronics and mass production QA simply leads to a certain number of units that will have defects. Denon has a pretty good track record and they back these higher-end units with a 3-year warranty so that should give you new owners some peace of mind.
Dealing with these issues can be a hassle, but it's just something you have to be prepared for regardless of how much due diligence you perform before purchasing.
I was prepared for a reasonable set of issues and I always figure there is a nonzero probabilty that any CE purchase will come out of the box DOA. I also don't think there is anything inherently wrong with either unit. In a former life I was a proces engineer at a manufacturing co. that did robotic assembly of computer components like memory, motherboards, graphic cards, etc. and have some insight on late-production issues. Most of the time the greatest care in manufacturing and testing is very early in the product cycle. My 4520 was built in May '14, probably using up the last of the chipsets/bare boards/etc. By the time production on an item is drawing to a close, there is generally a bit of scavenging going on. Daughterboards that failed an initial check but passed after some rework, chips that were found hiding in the stockroom, tendency toward sloppiness because the product is "old hat" plus pressures to set the line up for the next product are all factors that can impact the quality of the end product. It's all part of the landscape and generally not a problem.
My primary issue, the reason I abandoned the 4520 route, is that the window for "bring it back for a replacement if it doesn't work" had for all intents and purposes closed. On top of that I live on top of a mountain 45 minutes from the nearest BB(Assuming no traffic) so add that to the hassle of unwiring/rewiring/reconfig. I think I articulated the rest of my reasons back in post #9797
I don't think it would be fair for the recent concentration of issues to be interpreted as some basic flaw in 4520s in general. The internet tends to magnify such issues anyway, since few people will seek out threads like this just to say that their 4520 has been unobtrusively doing what it is supposed to for two years.