What is the average life expectancy of a DAC?

I disagree with the premise that one cannot hear the difference between dacs. Everything has a sound and sounds different through a top system. Obviously YMMV.

That said although I've done blind testing, I've not been able to level match, so my data is flawed. We didn't prefer the loudest unit, though, as usually hypothesized.

Having tried popular new dacs, I eventually ended up with an Audio Mirror R2R dac based on an obsolete Analog devices AD1865N-K. The nice thing about going with an old chip is that you don't have to chase the shiney new thing. And I preferred it to every shiney new dac I tried. I'm sure it'll still compare favourably to whatever is new in 10 years.

I was waiting for the FPGA people to weigh in, thankyou!  I have two dogs in this hunt...I have a wonderful Wadia 16 CD player/DAC I bought new in the 90s for what was then crazy money, and it gave me a great life span. It's still a useful component now running as a transport feeding my dCS Bartok. My first streamer two years ago was the entry level Naim, I then felt good enough about streaming and the FPGA approach that I upgraded to the dCS Bartok. When the first firmware update was made available with the Niam I was giddy with joy! For the first time in my audio life I got an update in my home for no hassle and no additional charge. I have also had one no hassle update from dCS so far. This software approach to the product life cycle issue was a definite part of my willingness to part with a dear $14,500 on the part of my system known for the most rapid changes. I'm counting on the FPGA technology to deliver for at least another 8 years. I might get itchy and feel the need to buy something new, but the updates should help protect my investment when I sell the dCS used. This is just a different approach, and I took it, hook, line and sinker, and maybe even the bobber!

All DAC's sound the same? Sorry, but my RME ADI-2 DAC does not sound like an iPhone. 

larshepping 

Ok, no reason to buy an external DAC at all if they all sound the same. Just use the DAC built into your computer or phone. End of discussion.

Why would they last any less than any other component? I'd say the guy that said 30 or 40 years is most likely correct.