Why Period Instruments?
I grew up playing modern flute and love playing early music on modern instruments. But, they are not what the composers had in mind and do not possess many qualities and capabilities the composers expected. The "evolution" of musical instruments has always required the sacrifice of certain capabilities that are less esteemed in favor of others that better suit the music of the times.
The earlier instruments provide a heightened sense of intimacy. They are softer and playing techniques require less pressure. They are more delicate and "painterly," with more coloration of tone. There is a heightened harmonic clarity, as the tones are much less obscured and evened out by vibrato, so the tones interact more clearly.
The tuning is more pure, both as early instruments are tuned differently and because of a sensitivity to pure thirds, which suffer in the equally-out-of-tune, evenly-compromised modern system. There is a very different tonal aesthetic and blend; modern instruments are more brilliant and have sounds that stand apart from one another, whereas the old ones have richer, fuller sounds on a softer dynamic level that more willingly blend into or, perhaps you could say, contribute to one another.
- Jeffrey Cohen