If your whole system costs $40,000....

how much will you invest in CD player with that sum?

I have been wondering my CD section is the weakest link, its around 10% of my system cost. I wonder people who are using some $10k players how much their whole system costs roughly...... Anyone can share their experience in upgrading their CD players?
Spend as much as you can comfortably afford. Base that on what sounds best to you. Don't try to "proportionatley" spend an amount, or you fence yourself in or out depending on the perspective. If the CDP that sounds best in your system is within your budget buy it. If you upgrade other components, as I have heard some do, your CDP won't be out of place with its performance level. I think the only time a price point vs. system cost would apply is a cartridge on a turntable. Example I wouldn't suggest that a person buy a Lyra Titan for a Rega RP1. No insult to RP1 owners but a 4500.00 Cart on a 500.00 Table would never reveal it's potential. My advise is put the sliderule away and listen listen listen, at least IMHO.
as a starting point to begin the search/comparison of components, i'd be it the 10-15% ballpark on 40k. 15% would be for a digital front end (dac/transport/pc audio set-up), not just a cdp. if i had to get a cdp only, i'd be closer to the 10% mark.

could be subject to change if i fell in love with something but it would get the ball rolling.

final answer...4-6k

what do i win??
Impromptu - given at a moments notice without significant thought like naming all the costs of your components with referring to any documents

Giving you a break - not being pilloried for inane, assinine or pointless meandering in your comments or thought processes caused by using a second language

Could be worse - Some may think it is just braggadocio on your part to laud a $40K expenditure rather than a legitimate question and respond accordingly.
In each of my systems the CDP/digital costs what the speakers cost. In both cases it is about 25%. Those numbers are pure coincidence and have little meaning as I listen to digital very rarely in those systems.

In the other two 'systems' where I listen to the most digital, the numbers are 80% and 2% and those ratios are both explicit and deliberate. I spent $100 on headphones to go with my iPhone, which I use as an iPod. The other is the $100 car stereo I recently bought to replace the one which died in my 10-year-old car (which is worth $5k on a good day).

I am thinking of buying a digital-only system for use in a tight space. In that case, given the headphones and amp and server I am considering, it will be about 60%.

Hope this helps.
To the naysayers, I say audio is supposed to be fun and for recreation/ enjoyment of music. This is a message board about all things audio. Some guys, I won't name any names, some guys are just mean-spirtited, nasty, and take themselves and these subjects way too serious. Lighten up! We audio enthusiasts and philes make up a very very small group of people in society! To most people we are are looked at as crazy for what we invest in this gear.