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signal level increases.
The MIC LIMITER
What is this MIC LIMITER setting about and when would one use it for best advantage? There's no easy answer for this, but a few considerations are in order before choosing this setting. First, the MIC LIMITER operates 'in addition' to the manual LEVEL KNOB setting and Mic ATT selection; this is not an 'auto level' function. Manual setting of the average VU peak level with the LEVEL knob is still just as important for recording quality reasons.
The MIC LIMITER keeps the VU levels from exceeding -2 dB VU and seems to start operating on reducing both channels (very quick attack/release auto-gain riding) as the signal level approaches about -3 dB VU. The result is it's nearly impossible to get clipping distortion regardless of where the LEVEL knob is set if the Mic ATT switch is correctly selected. The Mic preamplifier will not clip as long as the signal doesn't exceed the maximum handling ability of the MIC input with an additional + 20 dB of headroom added from limiter control. This is about 10 times above the native Mic preamplifier input voltage limitation. In other words, the 150 mV or 8 mV RMS mic input limitation, with limiter ON, becomes 1.5 volts and 80 mV RMS maximum before clipping as compared to being set in MANUAL, without the limiter!
Caution is advised as the 'overload proofing' benefit of the limiter is not without significant recording quality compromises. Its action is quite audible and best not used at all without very careful experimentation on what is tolerable or important in your recordings.
The audible limiter effects is quite apparent when the level knob is set too high for impulse type or brief intermittent overloads such as found with repetitive percussive sounds. It is quite apparent that the handling of short impulse type overloads without the limiter on usually sounds far better, is much less annoying, and produces a more usable recording. The reason for this is that in order to keep the signal from clipping, the overall level of all the sounds undergoes equal attenuation to not exceed -2 dB VU. The limiter's action is not (at least with this design) operating on just compressing the signal's excessive peak portion. It's downward-gain riding the entire signal (eliminating limiter compression type distortion), but is most audible and downright disturbing for brief and repetitive overloads.
Therefore, this type of limiter is most beneficial and least audible for steady and long duration overloads that are not percussive or quick to reappear in short repetition. Also, this type of limiter may seem more useful for documentary sound recordings that needs content continuity recorded amidst industrial ambient conditions where noise interference can be briefly and unexpectedly very loud, but quickly disappearing indefinitely.
A few examples: Recording of an impromptu interview or sounds of some continuous filmed activity in an ambient where unexpected, much louder sounds (like a loud factory horn blast) appear. These sounds may normally cause total overload obliteration of that portion. Having the limiter on should still allow saving this recording for having uninterrupted continuity of good quality in post.
In addition, this type of limiter, with its quick attack/release is most useful when dynamic quality is least important. For Example, assume that 'sound dynamics' is in the way of recording desired content and the ability to record without overload distortions is of prime importance. In this circumstance, adjust the manual level setting so most of the recorded sound is being limited. This should make a wide range of individual soft to loud sounds quite evenly compressed and total content easier to hear at one volume setting.
The recording of EFX ambient sounds may find the limiter useful for eliminating clipping distortions for an unexpected, long duration, and steady amplitude sound that is not repeating. The use of Limiter allows recordings of such unexpected sounds of potentially general usefulness. The limiter's actions with a steady overload will be more consistent in preserving important qualities and dynamics of this new loud sound. The limiting action will
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