In my experience, very few amplifiers can capture the sound of a real piano. In fact, some of the very most expensive amplifiers fall short on this test. Receivers Receivers offer the best value for someone putting together an audio system. Minisystems and department store systems usually offer very low quality speakers as part of the package so these are rarely good values. The price for a receiver is the least expensive way to acquire all the components required to put together a high fidelity system.
Receivers are by definition a very good value.
However, receivers never offer the ultimate in audio reproduction. The least expensive integrated amplifiers are receivers without tuners. Most of the Japanese made integrated amplifiers offer little or no sonic advantage over a receiver. It is possible to get very high quality sound from some integrated amplifiers. Integrated amplifiers typically offer smaller power supplies than separate amplifiers and use preamp components that don't quite match the best found in the highest quality preamplifiers.