To keep your system in balance, there really are no limits, ie if you go to $20K speakers, it could very well be beneficial to up-grade all your other components commensurately. So we can only report on out own experinces, IMO. That said:
Amp: $5K to $10K
Pre-amp: $5K to $10K
Source: $10K to $20K (digital)
Speakers: to $20K
Cheers. Craig
Amp: $5K to $10K
Pre-amp: $5K to $10K
Source: $10K to $20K (digital)
Speakers: to $20K
Cheers. Craig