What is most important part of a system?


I remember reading someone saying that the most important part of a system was the source. I thought "Wrong! Speakers are the most important".
 
Now, I have changed my mind. Source is the most important part.

Right or wrong but this is how I came to this conclusion;

I have tried the same system with a CD player and a turntable. By far LP sounds better than a CD. Btw, the system had all high-end amps, speakers, cables, etc.

What is most important part of a system for you?


celo
I agree that it all starts from a source, but if preamp is not able to deliver it without veiling and distorting the signal, the source makes no big difference. Most mid-fi preamps are actually not able to transmit everything that a good source has to offer. Therefore for lower cost and budget systems I suggest a decent passive preamp like TVC for example. Start building the system from speakers to source. If everything below is up to the task then it makes sense to experiment with a source components.
The source is important yes BUT the heart and soul of any music system is the amp. Get that right the rest falls into place 

I respectfully disagree.
Of course, it is critical that amp works well with your speakers and is powerful enough to properly control them, but the rest will not fall into place with this.
Maybe I never had any bad amps in my system, but in my experience the difference between (rightly chosen) amps is smaller than a difference between preamps and source components. 
IMO room/speaker interface and amp(s) to speaker interface.
Agree these are fundamental things, but assuming these are ok, then my ranking is 1. speakers, 2. preamp, 3. source, 4. amp, 5. vibration control, cables etc.