Alto Professional Live 1604

Introduction

The Alto Professional Live 1604 is a professional 16-channel, 4-bus mixer designed to provide comprehensive audio control for live performance environments. This manual provides detailed instructions for the setup, operation, maintenance, and troubleshooting of your Live 1604 mixer, ensuring optimal performance and longevity.

Important Safety Information

Power Source: Connect the unit only to an AC power outlet of the type specified in this manual or marked on the unit.
Grounding: Do not defeat the safety purpose of the polarized or grounding-type plug. A grounding-type plug has two blades and a third grounding prong. The wide blade or the third prong are provided for your safety. If the provided plug does not fit into your outlet, consult an electrician for replacement of the obsolete outlet.
Water and Moisture: Do not use this apparatus near water. Do not expose the apparatus to dripping or splashing and ensure that no objects filled with liquids, such as vases, are placed on the apparatus.
Heat: Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat.
Cleaning: Clean only with a dry cloth.
Servicing: Refer all servicing to qualified service personnel. Servicing is required when the apparatus has been damaged in any way, such as power-supply cord or plug is damaged, liquid has been spilled or objects have fallen into the apparatus, the apparatus has been exposed to rain or moisture, does not operate normally, or has been dropped.

Setup

1. Unpacking and Placement

Carefully unpack your Alto Professional Live 1604 mixer. Ensure all components are present and undamaged. Place the mixer on a stable, flat surface, allowing adequate ventilation around the unit.

2. Power Connection

Connect the supplied power cable to the AC input on the rear panel of the mixer and then to a suitable power outlet. Ensure the power switch is in the OFF position before connecting.

Rear view of Alto Professional Live 1604 mixer showing power input and various audio connections.

Image: Rear panel of the Alto Professional Live 1604 mixer, highlighting the power input, main outputs, and various auxiliary connections.

3. Input Connections

The Live 1604 features 10 balanced XLR inputs for microphones and 16 line-level inputs (8 mono, 4 stereo pairs) for instruments and other audio devices. Each microphone input includes switchable phantom power for condenser microphones.

Microphones: Connect microphones to the XLR inputs (Channels 1-10). Activate phantom power using the global switch if required for condenser microphones.
Line-Level Devices: Connect instruments, keyboards, or other audio sources to the 1/4-inch TRS/TS line inputs. Stereo sources can be connected to channels 9/10, 11/12, 13/14, and 15/16.
USB Audio: Connect a USB cable from the mixer's USB port to your computer for stereo audio input/output.

Top view of Alto Professional Live 1604 mixer showing all channels, faders, and controls.

Image: Top view of the Alto Professional Live 1604 mixer, displaying the full layout of input channels, faders, and master controls.

4. Output Connections

Main Outputs: Connect your main PA system or recording interface to the Main Mix Outputs (XLR or 1/4-inch TRS).
Aux Sends: Use the four Aux Sends to connect to external effects processors or monitor systems.
Subgroups: Utilize the four Subgroup Outputs for routing multiple channels to a single output, useful for managing groups of instruments or vocals.
Headphones: Connect headphones to the 1/4-inch headphone jack for independent monitoring.

Operating Instructions

1. Channel Strip Controls (Channels 1-16)

Close-up of Alto Professional Live 1604 mixer channel strips showing gain, EQ, and aux controls.

Image: Detailed view of individual channel strips on the Alto Professional Live 1604 mixer, illustrating the gain, equalization, and auxiliary send controls.

Gain: Adjusts the input sensitivity for each channel. Set this to achieve a strong signal without clipping (indicated by the PEAK LED).
Compression (Channels 1-6): Controls the dynamic range of the input signal, reducing loud peaks and boosting quieter parts.
Low Cut: Engages a high-pass filter at 75 Hz to remove unwanted low-frequency rumble.
EQ (Equalization):
- High: Adjusts frequencies above 12 kHz.
- Mid: Adjusts frequencies around 100 Hz to 8 kHz (sweepable on mono channels).
- Low: Adjusts frequencies below 80 Hz.
Aux Sends: Controls the amount of signal sent from the channel to the four auxiliary outputs. Aux 1 & 2 can be switched between pre-fader (for monitors) and post-fader (for effects).
Pan/Balance: Positions the channel's signal within the stereo field (left to right).
Mute: Silences the channel's output to the main mix and subgroups.
Solo: Isolates the channel's signal for monitoring through headphones or control room outputs without affecting the main mix.
Sub 1-4: Routes the channel's signal to the selected subgroup(s).
Main L-R: Routes the channel's signal directly to the main stereo mix.
Channel Fader: Controls the overall volume level of the channel in the mix.

2. Main Section Controls

Close-up of Alto Professional Live 1604 mixer main section showing graphic EQ, effects, and master faders.

Image: Detailed view of the master section of the Alto Professional Live 1604 mixer, including the graphic equalizer, Alesis DSP effects, and main output faders.

Graphic EQ: A 9-band graphic equalizer for fine-tuning the overall frequency response of the main or monitor outputs.
Alesis DSP Effects: Access 100 high-quality Alesis digital effects, including delays, reverbs, chorus, and flangers. Use the Program knob to select an effect and the DFX to Aux/Main controls to send the effect to the desired output.
Subgroup Faders: Control the master volume of each of the four subgroups.
Main Mix Fader: Controls the overall output volume of the stereo main mix.
Headphone Level: Adjusts the volume for the headphone output.

3. Official Product Video

Video: An official overview of the Alto Professional LIVE Series Mixers, demonstrating key features and applications. This video is provided by InMusic, the manufacturer of Alto Professional products.

Maintenance

Cleaning: Regularly wipe the mixer's surface with a soft, dry cloth. Avoid using abrasive cleaners or solvents. For stubborn dirt, a slightly damp cloth can be used, followed by a dry cloth. Ensure no liquids enter the controls or openings.
Dust Protection: When not in use, cover the mixer with a dust cover to prevent dust and debris from accumulating in faders and knobs, which can affect performance and longevity.
Storage: Store the mixer in a cool, dry environment away from direct sunlight and extreme temperatures. If transporting, use a protective case.

Troubleshooting

Problem	Possible Cause	Solution
No sound output	Power not connected or switched on. Main Mix fader or channel faders are down. Mute button engaged on channels or main mix. Output cables disconnected or faulty. Speakers/amplifiers not powered on or connected.	Check power connections and switch. Raise faders to appropriate levels. Disengage mute buttons. Verify all output cables are securely connected and functional. Ensure all connected audio equipment is powered on and correctly connected.
Hum or noise in audio	Ground loop issue. Improper cable shielding. Gain levels set too high. Known USB interface issue (specific to some units).	Ensure all equipment is on the same electrical circuit or use a ground loop isolator. Use high-quality, shielded cables. Reduce gain levels on channels and main mix. If experiencing hum when using USB, try connecting the main outputs to an external audio interface instead of direct USB connection to the computer.
Distorted sound	Input signal too hot (clipping). Output signal too hot.	Reduce input gain until PEAK LED no longer illuminates. Lower channel faders or Main Mix fader.
Effects not working	DFX to Aux/Main controls are down. Effect program not selected. Aux Send levels to DFX are too low.	Increase DFX to Aux/Main levels. Select an effect program using the Program knob. Increase the Aux Send level on the desired channel(s) to send signal to the internal effects processor.

Specifications

Feature	Detail
Brand	Alto Professional
Model	Live 1604
Number of Channels	16
Item Weight	13.1 Pounds
Connectivity Technology	Aux, XLR, USB
Power Source	Corded Electric
Frequency Response	20 Hz - 20 kHz (typical)
Audio Input	XLR, 1/4-inch TRS/TS
Voltage	240 Volts (check local power requirements)
Manufacturer	inMusic Brands Inc.
GTIN / UPC	644535662298, 816311011044

Warranty Information

The Alto Professional Live 1604 mixer comes with a 1-year parts & labor warranty. Please retain your proof of purchase for warranty claims. For detailed terms and conditions, refer to the warranty card included with your product or visit the official Alto Professional website.

Customer Support

For technical assistance, product registration, or further information, please visit the official Alto Professional website at www.altoproaudio.com. You can find FAQs, software downloads, and contact information for support services.