Mackie 1640I User Manual

Owner's Manual   

15

Another way to consider low-cut’s function 
is that it actually adds fl exibility during live 
performances. With the  addition of low-cut, 
you can safely use low equalization on vocals. 

Many times, bass shelving EQ can really benefi t 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.

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!

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 fi rst, 

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.

If you haven’t already, please read the level-setting 

procedure on page 3. 

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. 

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.

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 benefi cial 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.

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 specifi ed 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 fi nd 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.