Speakers usually. However, amps these days sound so different from one another that they’re becoming a more important component all the time. It used to be that if you weren’t building your system around your speakers you were going about it wrong. That’s not necessarily the case anymore. There are so many small shops building top notch amps for very competitive prices, amps have suddenly become almost as important as speakers in building a system. In some cases the amps are more important, especially if you're looking for a specific type of sound.
What is the most important component to consider while building a new system?
I recently viewed a You Tube video featuring Paul McGowan from PS Audio discussing the most important component when building a new system. I love Paul's video's and feel they bring a personalized touch to the discussions of all things audio. In the video mentioned Paul took a generalized approach in stating the speakers were the most important component to consider and that the relevant importance of each successive component rested in the chain down stream of the speakers. I am writing this to humbly disagree. I am in the mist of building a new system from scratch over the past 9 months. It has been my experience that if proper care is taken to the quality of the amp. pre-amp. and cables (with an emphasis on cables) you can get away with relatively inexpensive speakers that sound better than they have a right to. This is my own opinion based on recent experiences.