C1648, C2448, C3248 & c1648p 4-BUS MIXERS
Quick Start Up
If you’re like most new owners, you’re probably in a hurry to plug your mixer in and use it. Here are some brief instructions to get you going quickly. With the mixer unplugged and the unit turned off, complete the following procedures:
1. CONNECTING AC POWER TO YOUR MIXER
•The mixer can be used with 120 or 240VAC (it automati- cally switches internally)
•Use only a grounded (3 prong) power outlet to prevent a shock hazard. This gives the quietest grounding for your mixer.
2. CONNECTING INPUTS TO YOUR MIXER
•For low level balanced devices such as microphones, plug into the balanced MIC inputs using a shielded microphone cable with XLR connectors.
•For high level balanced or unbalanced devices such as 
instruments & keyboards, plug into the LINE input jacks
using a shielded cable with 1/4” phone plugs. Adjust the GAIN knob for the mic or line input being used.
3. TURNING YOUR MIXER ON
•Adjust all channel FADERS and master level controls to their off positions
•Adjust all channel’s Hi, Mid, and Bass controls and the two master 9 Band GraphiCS to their center positions.
•Adjust the Channel “PAN” controls to their center posi- tions.
•Turn the mixer on by the rear panel power switch and watch for the power LED. Your mixer is now ready to operate.
C48 series CONTROLS
channel features
1. 1/4” Line INputs
The line connectors are for connecting balanced and unbal- anced instruments and line level sources such as drum machines, keyboards, ETC.
2. XLR MIC INputs
The balanced Mic inputs are for connecting microphones that use XLR connections. Both the Line and XLR MIC inputs can be used simultaneously.
3. Channel Insert/direct out
To insert channel effects, compressor, etc. use a 1/4” TRS (Tip Ring Sleeve) cable (see Inserts and Direct out illustration on page 5 for TRS details). To achieve a direct out from the channel, insert a standard 1/4” cable to the first “click” (1/2 insert).
4. Gain
The gain controls the input level for the channel. If the gain is set too high, the PEAK LED will flash and distortion may occur. Decrease the amount of gain until the PEAK LED does not flash. It is important that the gain control should be kept next to the PEAK LED flash point to maintain the lowest noise of the channel. You can use the channel PFL switch to monitor the channel input level and use the meters to adjust the gain control to 0dB. This will give a good reference where the GAIN control should be set.
5. Low cut switch
A 75 Hz low cut filter helps eliminate unwanted low frequen- cies. Great for reducing “boom” noise from mic stands or from acoustic/electric guitars. Turning up the LOW EQ when using this filter can help create a punchier bass response.
6.Active 4 band EQ with DUAL mid sweeps
The C48 series mixers provide studio EQ. The ±15 dB boost or cut gives an overall 30 dB range for powerful EQ control. The active circuits deliver deep bass from the 20-80 Hz LOW control. The MID controls work at 45Hz to 10kHz, depend- ing on the MID FREQ controls. The HI control functions at 11-20k for crisp highs.
Start out with all tone controls at their center “zero” position. Determine which position your MID FREQ sounds best, then cut or boost your HI, HI MID, LO MID, and LOW frequencies as needed. If you are trying to mic instruments such as acoustic guitar or drums, try various mics and mic placement before adjusting your tone controls. A typical setting may be: HI -3, HI MID+5 (MID FREQ set at 4kHz), LO MID -4(MID FREQ set at 700Hz), and LOW +3. Don’t be afraid to adjust the HI and LOW controls to get good presence and depth while reducing the LO MIDs to clean up your sound. This is one of the keys to great sound.
7.Hi & lo MID SWEEPs
These controls allow you to select which frequency (from 200Hz-10kHz or 45Hz-2kHz) that the MID controls will boost or cut. By adjusting the MID FREQs, you can select the exact
frequency that will best complement various inputs. 700Hz and 4kHz are recommended settings for the MID FREQ control for guitar and vocals.
8.monitor 1 THRU 6 send controls
The channel MONITOR controls allow you to create six independent monitor mixes. The MONITOR signals (pre-EQ, pre fader) are routed to the master MON 1, 2, 3, 4, 5 and 6 controls (#22) respectively before going to the XLR output connectors (#40).
9.Eff 1 & EFF 2 send CONTROLs
The EFF 1 or eff 2 control sends signal (post EQ, post fader) from the channel to the master EFFECTS 1 or EFFECTS 2 levels to the internal processors (#18) and to the EFF 1 or eff 2 output (#38).
10. PAN CONTROL
Each channel’s PAN control allows stereo imaging by pan- ning Left or Right during recordings or live performances. The PAN control also works for the sub-mix groups. A center position will send a channel’s signal to a pair of sub-group faders (1-2, 3-4when assigned). By panning hard left, the signal is routed to only sub-group fader 1 or 3 when assigned. Panning hard right routes the signal to sub-mix fader 2 or 4. Dual element pan controls provide 15dB greater separation than standard pan controls
11. channel SIGNAL GREEN LED
The signal LED is pre-fader and post EQ. This LED helps the operator verify that the channel is receiving a signal from the mic or instrument inputs even when the channel fader is off.
12. CHANNEL RED PEAK LED
This peak indicator is pre-fader and post EQ. If the PEAK LED flashes, the channel needs a reduction with the GAIN control (#4) to prevent distortion. A “solid” lit PEAK LED indicates that the channel has been muted.
13. CHANNEL MUTE SWITCH
The MUTE switch will interrupt the channel signal. This feature saves having to reset your faders and monitor sends. The PEAK LED will light solid ON with no SIG LED.
14. CHANNEL PFL SWITCH
This switch allows the operator to listen to a channel (pre fader listen) in the headphone mix to set tone and gain levels as well as see the channel at the LED meter output (#33).
15.CHANNEL ASSIGNMENT SWITCHES
These switches assign the channels’ signal to the Master L/R faders, or to the Sub-Groupfaders 1 & 2, 3 & 4 for sub-mixing in stereo pairs. For mono, pan fully to the left and assign a channel to Sub-Group fader 1 or 3 only. Pan fully to the right and assign a channel to Sub-Group fader 2 or 4. Likewise assigning the L/R switches sends the channel directly to the main L or R faders.
16.CHANNEL FADER
The CHANNEL FADER adjusts the output level of the chan- nel. The signal will go to one or more of the Master Faders, depending on both the Channel Assignment switches and the PAN control. Calibrated 60mm faders with audio tapers are
featured for smooth fade-outs. Slide all faders down when connecting your inputs.
17.MIC PHANTOM POWER SWITCH / RED
LED
This switch provides +48v power for condenser mics such as Carvin’s CM90E in groups of 8 channels. This leaves the remaining MIC inputs for sources that don’t require phantom power. The LINE inputs are unaffected.
MASTER SECTION
18.DUAL STEREO 24-BIT EFFECTS PROCESSOR
The internal 24-BIT stereo processors receive signals from the channel EFF1 and EFF2 controls and the master EFF1 and EFF2 controls. If the adjacent PK (peak) LED flashes, reduce the level from the channel or master EFF1 or EFF2 send controls. A “solid” PK LED will show EFFECTS 1 or 2 have been muted by the MUTE switches. The RETURN control will adjust the volume level of the selected effects. Remember each channel has its own two EFFECT sends that will send the signal to the effects processors. The red PK LED will indicate when the effects signal from the channel is distorting. Reduce the level of the channel EFFECT control until the PK LED stops flashing.
EFFECT AND PARAMETERS
a.)ECHO: When the SELECT control is at the “seven O-clock” position, it is selected to the first ECHO setting where you get a single repeat echo (minimal regeneration). Turning the PARAMETER control to 1 will provide the shortest delay time between the original signal and the echo. Increasing the PARAMETER control to the right will increase the time delay between the original signal and the echo. To increase the number of echo repeats, turn the SELECT control clockwise to “9 O-clock” (maximum regeneration).
b.)REVERB: When the SELECT control is at the “ten O-clock” position, it is selected to the first REVERB setting. Turning the SELECT control clockwise will increase the amount of high frequencies in the reverb. Turning the PARAMETER control to 1 will provide minimal decay time of the reverb. Increasing to the right will increase the reverb decay time.
c.)CHORUS: When the SELECT control is at the “one O-clock” position it is selected to the first CHORUS setting. Turning the SELECT control clockwise will increase the amount reverb in the chorus. Turning the PARAMETER control to 1 will provide a minimal chorus depth setting. Increasing to the right will increase the chorus depth.
d.)FLANGE: When the SELECT control is at the “four O-clock” position it is selected to the first FLANGE setting. Turning the SELECT control clockwise will increase the flanger’s speed. Turning the PARAMETER control to 1 will provide minimal flanging depth. Increasing to the right will increase the flanger’s depth.
To send effects to the monitors, use the “TO MONITORS” controls, MON 1/MON 2 & MON 1/MON 3. The center posi- tion on both controls is OFF.
19.SEND 1 & 2
Sends signals from the channel EFF 1 and EFF2 controls to the internal processors and to the EFF1 and EFF2 output jacks.
20.RETURN 3 L-R
Receives stereo or 2 mono effect signals from the RETURN 3 L /R jacks. These signals will also be present at MON 1 (#40).
21. RETURN 4 L-R/ USB IN
Receives a signal from the RTN4L/R1/4” jacks (#39) and from the rear USB port. These signals will also be present at MON 1.
22. MONITOR 1-6 CONTROLS
These are the master outputs for the six monitor sends. These correspond to the Mon 1-6XLR output jacks (#40).
23. GROUP/SUB-MIX FADERS 1-4
Once a channel has been assigned to one of these faders, the mixing process is simplified to using these four faders. If these faders are not assigned to the Master L-Rfaders (#28), then each fader is bused to the corresponding 4 group 1/4” outputs (#41). By assigning the 4 faders to the Master L-Rfaders, the operator can use the faders to sub-mix groups.
