As someone who has recorded classical music for 17 years, with many of those recordings involving piano either solo or as an accompaniment to solo instrument, I must say that both the recording and replay of piano represents perhaps the benchmark challenge. I have seldom heard piano reproduced with much of the reality intact. One of the mics I use - an $8000 Schoeps KM6 Sphere - was chosen mainly for its supposed abilities with piano.
After all this time, my conclusions as to what is needed for replay are:
1. very high dynamic capabilities, i.e. very little power compression, that is, if a speaker produces 90dB at one watt at representative points across the audio band, say, 50, 100, 500, 2000, 10,000Hz, then it should produce 100dB with 10 watts and 110dB with 100 watts at all those same frequencies. Most speakers compress before the 100W point, blunting dynamics. I would say the minimum requirement for piano at near realistic levels would be around 115dB clean for the peaks.
2. linear and non resonant behaviour between 40Hz and 300Hz, especially, with the aforementioned dynamic capability through that range.
3. (perhaps obviously) flat response through the rest of the range, and more than just on axis but within 30º around that axis.
I am currently in the process of replacing my studio mid field monitors and piano reproduction will be a high priority for me. Based on testimonials from professionals in the field, some based specifically on their abilities with piano, I am going to take a chance on SP Technologies Timepieces and will be using NuForce ref 9 amplifiers. I say take a chance because I will not be able to audition them beforehand, however there is a free (including return shipping) 30 day trial period. These would appear to satisfy all the criteria mentioned above.
Russell
