Jump to content

Schallfeldwebel

Members
  • Posts

    1
  • Joined

  • Last visited

Everything posted by Schallfeldwebel

  1. During the final phase of the development of the CMD 2U I have been testing it in the field. I found the 10 dB gain mode unusable, and too noisy. In the field I had no way to add more digital gain to the low output of the microphone, and I simply could not hear well enough what I was recording from my headphone. In the beginning designer Christian Langen did not agree with me, his opinion was the noise wasn't a problem, and the + 10 version allowed for sound levels up to 135 dBA SPL. A typical designer, non-listener judgement. Schoeps made a + 30 dB version for me, and I found that much more usable. The +10 version, although more noisy was sounding cleaner. The +30dB version sounded warmer, which either is due the lower noise, or because of higher amount of harmonic distortion. The chip which was used ran on very low voltage and took not much current. I have looked up my old e-mail converstions with Langen, but I cannot find the chip model anymore. What I Iiked about the digital CMD was it sounded more pleasant to my ears than a CMC5 with Lake People V26 preamps. But the difference is minimal, probably the most striking was the tighter bass. Since every AD chip is stereo, I did not understand why the designer has not inplemented two settings of gain, e.g. +10 and +30, and use the 2 channels available. Since AES digital format is a stereo output, the recorder can record the low gain signal and the high gain signal simultaneously, and the sound engineer can decide in post which channel to use. If the signal is loud and distorted in channel 2, channel 1 can be used. If the signal is low, and channel 1 is too noisy, channel 2 can be used. Neumann avoids this problem by using two channels, and switch automatically between the two settings and compensate for the differences in the output, this is called gain staging, invented or first used in the early 90s by Prism Sound. The Beyer Dynamic MCD 100 also works with gain staging by combinng two 18 bit converers into a 22 bit dynamic range. I never bought the CMD 2U, because I heard a new version following the new standard for digital microphones was on its way, but three years later nothing has happened.
×
×
  • Create New...