@soix
If you had any technical knowledge on electronics then you’d know that you do NOT have to build the exact same piece of electronics to understand the location and nature behind a failure. Especially when that failure is a mechanical issue in the basic board itself.
SMc isn’t saying there are deficiencies in their special top secret circuit design and they had to change this design. SMc is saying the basic board has mechanical problems. Manufacturers like SMc do not produce their own boards, they get PCB manufacturers to produce them. Whether that board is in a Kenwood, Marantz, Krell, McCormack, etc. most are from the same PCB manufacturers and run side by side on the same production line using the same processes. So anyone who has worked on repairing boards in electronics is qualified to make these statements about the repair of such.
Tell u what — I’ll go back to the guys WHO ACTUALLY BUILT THE AMP and tell you why you’re absolutely wrong..
If you do not understand that there may be a possible motivation of profit behind SMc telling people that their original amps input boards are not repairable then I do not know what to tell you. So yes, please do keep asking the fox to tend to the hen house. When you talk to SMc ask them to come onto this thread and post closeup images of the mechanical issues on these completely irreparable input boards. Certainly SMc has documented this issue many times over. There are other folks on this thread that seem knowledgeable about board repairs and I’m sure that they would like to see high resolution images of the failures too.
Your initial post reads as a person who needs to justify the expense of this purchase and is angry that others can still sell their functioning amps for a decent price.
So lets address your initial all or nothing statements,
While they’re great amps, and I happily owned a DNA 0.5 RevA for 20 years, they’re all gonna fatally fail.
No ALL DNA amps are not going to fatally fail, not by a long shot. Whether the number that survives a decade from now is my butt number of 50% or not, your statement is extreme and ridiculous. I personally believe that number will prove to be much higher than 50% and will probably be better than say a Krell or Levinson of the same vintage. BTW There’s a very good way to judge this reliability. When you begin to see far more dead DNA amp’s than working units for sale on the common audio sale sites then you can surmise that extremely high failure rates are present. I mean, based on your own opening statement, they cannot be repaired right? So they’ll remain dead until they’re sent to SMc to be upgraded or they’ll be sold as dead units and if they’ve been upgraded by SMc then the sales ad will state this fact.
Because their input board is at the end of its useful life, and when it fails your amp is dead and not repairable by anyone — not even SMcAudio. It’s a boat anchor.
Other’s have already pointed out your error in this statement. Unless a board has been completely burnt to the point it becomes conductive then it is generally repairable. However, I’ve seen boards that had burnt sections and people cut out the burnt section and P2P wired in that portion of the circuit. I’ve seen double-sided boards that literally snapped into two pieces and the tech repaired them by rebuilding each individual trace with a solid joining wire soldered to the traces and in the end creating a stronger board. In the end, whether or not a unit is repairable most of the time depends on the amount of a time and effort a tech wants to put into that unit. I’ve personally worked on a number of components over the years from the 1960’s and 70’s that had far more delicate and easily damaged circuit boards in them than the DNA input boards.
