I record live orchestral concerts using a Tascam DR-100 and Tandy/Realistic PZMs. I have to use these mics for various reasons including the layout of the venue and the need to carry both musical instrument and recording gear. Mics have 1/4 inch jacks and are connected to the DR-100 using XLR adapters. Recording settings WAV, 16 bit, 44.1 sampling frequency. Whilst the sound is fine, the recording level is very low, even with mic gain set at High and input level at max, and needs normalising before burning CDs. I've had these electret mics for 20+ years; will there have been any deteriorisation in performance in that time? If so, will it manifest itself in any other ways, eg noise of any description? Example via link to a short (1 minute) excerpt, (Expired Link Removed) Thanks for any help/info offered.