Is the DAC the digital equivalent of a cartridge.

A cartridge change is a big change, not quite as big as a loudspeaker change but right up there. DACs do sound different but not to the same extent as a cartridge change. 

file/silver disc = vinyl----media

transport/streamer = cartridge----reading + tiny signal

dac = phono stage---converting + boost + analog output

Both are transducers. So yes, and….?

I mostly agree with this. the importance of a DAC is underestimated by some.

@carlsbad yeah it is mostly ignored by the people in the 80s who were told ads naseum about how great digital was.

And some of that is from posts like this:

My analog and digital ends have outstanding and very very similar sound quality. The cost breakdown (and I did not just arbitrarily throw money at it )

Streamer $22K - DAC $17K

Turntable $20K - phonostage $17K

I assure you that if the streamer value was halved the sound quality to ~$10K, the digital end sound quality falls precipitously. I have tried it. Also I increased the DAC cost from $17K to $22K and got virtually identical results. Of course you cannot abstract this to all systems… but I have done a lot of work to minimize the cost of each of my components and get the most sound quality.

I have a $1500 DAC, which measures as good as it gets.
And an Intel NUC.
Why do I need all that other crap to get sound?

DACs and ADCs are pretty easy things to do.
They have been telling us for 35 to 40 years that it is better and cheaper.

It is cheaper to distribute files on the internet, but the rest is not really a benefit to me.

all analogies have limits, as does this one