Mackie Onyx 1640i Owner's Manual - Page 15

Another way to consider low-cut's function is that it actually adds flexibility during live performances. With the addition of low-cut, you can safely use low equalization on vocals. Many times, bass shelving EQ can really benefit voices. Trouble is, adding low EQ also boosts stage rumble, mic handling clunks and breath pops from way-down low. Applying low-cut removes all those problems, so you can add low EQ without blowing your subwoofers. 24. INPUT (LINE or FW 1-16) All 16 channels may be fed either from the mic/line inputs, or by up to 16 outputs from a computer via FireWire. This switch lets you choose (on a per-channel basis) whether the channel is accepting a mic/line input or a FireWire output stream from your DAW. While tracking, you will likely want all of these switches in the "up" position so you can hear the inputs. When overdubbing, you will likely want whichever tracks are already recorded to the DAW to stream back into the board (e.g. drums on 1-8 while overdubbing bass on channel 9, so you'll want the input switches on channels 1-8 in the FW position). And when you are ready for full analog mixdown, you will probably want all of these switches in the "down" position so you can do a full 16-channel "tape style" mix - the way mixing was meant to be! If the signal originates through the mic XLR jack, there will be 0 dB of gain with the knob fully down, ramping to 60 dB of gain fully up. Through the 1⁄4" line input of all 16 channels, there is 20 dB of attenuation fully down and 40 dB of gain fully up, with unity gain "U" at 11:00. This 20 dB of attenuation can be very handy when you are inserting a hot signal, or when you want to add EQ gain, or both. Without this "virtual pad," there is more chance of channel clipping. 27. SEND FIREWIRE PRE/POST Each channel of the mixer can send a FireWire output to your computer or DAW. The FireWire output from each channel can be tapped before (pre) or after (post) the channel EQ. (The output is always pre-fader.) If you want the mixer EQ to affect the FireWire recording, then set this switch to post. This is useful in recording channels in a studio (where the recording includes the beneficial effect of our Perkins EQ). If you would rather record the straight signals from a live performance, and EQ them later in your DAW, then set this switch to pre. This is good for live work, where you may have added EQ to adjust for the room, and yet not want this added to your recording. 25. HI-Z SWITCH (Chs. 1 and 2 only) Engage this switch if you want to connect guitars directly to the 1/4" line inputs of channels 1 or 2. Without this switch, you need to use a DI box first, before connecting guitars. If these switches are not pressed in, guitars will not sound good, particularly the high frequency response. Plugging a guitar into a lower-impedance line-level input can result in the loss of high frequencies, causing an unnatural and dull sound. Normally, you must use a direct box between a guitar and a mixer's input, which serves to convert the impedance of the guitar from high to low. The hi-z inputs on channels 1 and 2 make the need for a direct box unnecessary. However: The hi-z inputs are unbalanced (when the switch is in), so if you're doing a live show and running a long cord between the instrument and the mixer (say over 25 or 30 feet), it is best to use a direct box with a balanced output to avoid picking up noise over the length of the cord. 26. GAIN CONTROL If you haven't already, please read the level-setting procedure on page 3. CHANNEL EQUALIZATION (EQ) All 16 channels have 4-band EQ with shelving high, shelving low, and peaking hi-mid and peaking lo-mid with adjustable mid frequency. Shelving means that the circuitry boosts or cuts all frequencies past the specified frequency. For example, the low EQ boosts bass frequencies below 80 Hz and continuing down to the lowest note you never heard. Peaking means that certain frequencies form a "hill" around the center frequency. With too much EQ, you can really upset things. We've designed a lot of boost and cut into each equalizer circuit because we know that everyone will occasionally need that. But if you max the EQ on every channel, you'll get mix mush. Equalize subtly and use the left sides of the knobs (cut), as well as the right (boost). If you find yourself repeatedly using a lot of boost or cut, consider altering the sound source, such as placing a mic differently, trying a different kind of mic, a different vocalist, changing the strings, or gargling. The gain knobs adjust the input sensitivity of the mic and line inputs. This allows signals from the outside world to be adjusted to run through each channel at optimal internal operating levels. Owner's Manual 15