Which is the most important part of a stereo system?


My system consists of a pair of B&W 630's, an old Denon 50 watt reciever (DRA-550) from the mid 80's, a Marantz CD5004 cd player, and now a Pro-ject Debut Carbon DC Turntable.  I'm pleased with the speakers and the cd player and while the Denon sounds good it has some issues and I want to upgrade.

I'm planning on returning the Pro-ject TT and getting a higher end TT.  I'm also looking into getting a new amp pre amp with a internal DAC.

Is the source the most important? The speakers? 

Please Help!
klimt
terry9

I did the test. I built a special cabinet to be a Faraday cage, then used theoretically optimal 99.99% pure silver conductors inside teflon tubular insulators which barely contacted the conductors, which were separated by 50mm for near-zero capacitance. ETI connectors. Compared to premium microphone cable with ETI connectors. Difference negligible.

>>>>>Strictly speaking, that is not a scientifically valid test. That’s the problem generally with cable tests and cable comparisons. There are variables that are not accounted for in the test. Examples:cables not sufficient broken in; cables not cryod; cables’’ directionality not accounted for; the possibility of errors in the test system. Therefore I am inclined to throw your test out. 
Years ago, WireWorld invented a Cable Comparator. It accepts several interconnects. It has a shift knob to quickly switch between them
For me there is no singular most "important" component.  Rather, there are important choices in the development of a system.

In no special order, type of speaker, i.e. planar, box speaker, K-horn, etc.  The choice here will often lead to amplifier choice for a variety of well documented reasons.

Then there are source choices to be made. Are you a vinyl person, or do you stream, perhaps SACD / CDs acquired over tume.

Are you a tube enthusiast, either amplifier or pre amplifier?

Any of these choices could be the most important to you, but perhaps not me.  Thus, the fragmented nature of the discourse here.

So I will share my most important choice(s).  I am a Maggie fan and that has driven my amplifier choice as well as pre amp.  Others will have different first choices, there is mo right or wrong, just individual preference IMHO.
Your room, room, and more room impact the sound more than you know. A system is a whole, they work together, power cords impact gear more than any other cable, the wrong power cords and can make a good piece of gear sound like crap. So don’t look at if I change one piece of gear as the only thing to improve your system, start with the room your using 1st and in most cases that will cost far less than a new piece of gear. Speakers interact with the room, how does a speaker sound only as good as your room allows. I see so many speakers on Youtube that are big $$$$ ones and they are in a room that kills the sound of all their gear and money they spent, it is a waste of money in a reverb hard space. Audio is like cooking what spices do you like? To each his own, tubes or Solid State or Class D, H, all have their followers, its what you like for your ear and enjoyment, no reviewer can get your system right for you, learn from experience what you enjoy the kind of sound you like then build towards that goal. We are only 0.5% of the consumer market, so we are a rare breed. Which is why what format we like makes no impact in the big picture of electronic sales. SACD, MQA are good formats but the 99.5% of the buying public doesn’t care, that why they all slowly die out, not that they are no good but most people don’t care, they want portable so a pair of earbuds and a cell phone and they are good to go, along with digital radio streaming. Audiophiles are a hobbyist group who enjoy the art of reproduction and will sit and listen, Boomers are the market when they go the market goes with them. I know of none of all my family and their family nor their friends have as much wrapped up in their home system as the cost of my power cords. They got other priorities, like kids, education, gaming, etc.