Flat mics, or those with smooth, wide, gentle presence peaks are generally preferred over those with more aggressive presence peaks. Some engineers prefer flat, neutral preamps that emphasize accuracy, while others prefer preamps with more strident characteristics. In a live recording, if there is an audience present, or the event is being filmed, microphone choices and techniques may be more restricted, the audience and cameras need their view to be as unobstructed as possible, so small diaphragm condenser mics are usually used. In a good acoustic, a great recording of a small to medium-sized ensemble is possible with just a single stereo microphone array. Large classical ensembles sound best in reverberant concert halls, and those same halls are the preferred environments for recording them- without using artificial reverbs. Without an audience and the noise the audience generates, a concert hall or large church is ideal for large ensemble recording.