M-AUDIO 49i ユーザーズマニュアル

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KeyStudio 49i User Guide
KeyStudio 49i Audio Setup and Controls
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Using the Mic and Instrument Inputs
Channel 1 of M-Audio KeyStudio 49i is a high gain, low noise microphone preamp  It is a low impedance input with an XLR 
connector for a dynamic microphone  Channel 2 contains a high impedance instrument preamp, designed to add gain to an 
electric guitar or bass, or even a high impedance microphone  You may also attach a direct box or passive transformer to the 
M-Audio KeyStudio Microphone Input (Channel 1), which will then allow you to plug another electric or acoustic guitar or other high 
impedance instrument into the M-Audio KeyStudio’s Mic Input  Additional information on using the Mic and Instrument inputs can be 
found in the next two sections  
Setting Input Gain
M-Audio KeyStudio 49i provides up to 45dB of gain on the Channel 1 Mic In and 35dB of gain on the Channel 2 Instrument 
In  Microphones, electric guitars, and electric basses typically emit a low signal level, requiring a “pre-amp” such as M-Audio 
KeyStudio 49i provides  
Plug in your microphone or instrument with the gain controls turned down, and turn the gain up incrementally while testing 
the mic or playing the instrument  When the green signal LED shows fairly consistent activity, you’ve reached a good signal 
level for the M-Audio KeyStudio mic preamp  Some users may wish to experiment a little further to find what audibly might be 
referred to as a “sweet spot ” Note that when the red clip LED lights, it is indicating that the preamp output is very close to 
peaking (-1 dB), and the input signal is on the threshold of distorting  Let your ears be the judge, but when the clip LED lights 
and stays lit, you are approaching or have reached distortion in your M-Audio KeyStudio signal  
The best method to find the ideal recording level is to turn up the input gain, and then turn it down once you’ve started to 
clip the input signal  You must also consider the level that is being sent from M-Audio KeyStudio to your recording software  
Check the input meters within your software and make sure that they are neither too low nor clipping (too “hot”)  An 
adjustment in gain on M-Audio KeyStudio may be necessary, but your optimal recording level within your software should 
approach but never reach the maximum level  Additionally, because the M-Audio KeyStudio 49i preamps provide quite a bit of 
gain, it is recommended to turn the gain all the way down on unused inputs  You will find more information on setting record 
levels in the manual of your music software  
Using the Aux Inputs
M-Audio KeyStudio 49i has a pair of line inputs labeled “Aux Input ” They are designed to interface with both the left and right input 
from a stereo source, such as a synthesizer, drum machine, or CD player 
Using computer software (like Ableton Live Lite or M-Audio Session) to record your MIDI sequences or KeyStudio 49i piano 
performances as audio tracks allows you to apply software plug-in effects to these tracks  MIDI sequences from an external sound 
module can be recorded by connecting your external MIDI module’s audio outputs to your KeyStudio Aux inputs  In Local On mode, 
the KeyStudio 49i built-in piano sound can be recorded as audio by selecting the inputs of KeyStudio 49i within your recording 
software and then playing the keyboard  After recording, you can mix those tracks with other audio tracks (such as vocals and guitar) 
entirely from within your computer  
Important: The Aux inputs and the built-in piano sound blend with the Instrument and Microphone inputs before their 
signals are sent to a connected computer via USB. If the Aux inputs or the built-in piano sound are used simultaneously 
with the Instrument and Microphone inputs, the resulting recording will be a mix of the various signals. It is not possible 
to separate these blended signals after a recording has been made. If you want to edit or mix the Piano, Microphone, 
Instrument or Aux inputs after the recording has been made, then you will need to do the recording of each of these sound 
sources one at a time and on separate tracks.