ULTRACOUSTIC ACX450/ACX900/ACX1800

1. INTRODUCTION

Thank you for choosing the ULTRACOUSTIC amplifier. You have purchased a modern 2-channel amplifier that guarantees excellent sound quality for various applications yet is easy to operate. The ULTRACOUSTIC comes with a wide range of features such as two integrated, 24-bit multi-effect processors or the FBQ Feedback Detection system which help you to fine-tune your sound. Due to the many possibilities of connecting external effects units and playback feeds, the ULTRACOUSTIC is a real all-rounder leaving nothing to be desired.

+Please read this manual to familiarize yourself with the control elements of the unit and its functions. After you have carefully read this manual, keep it for future reference.

1.1Before you get started

1.1.1 Shipment

The ULTRACOUSTIC was carefully packed at the assembly plant to ensure secure transport. If the cardboard box is damaged, please inspect the ULTRACOUSTIC equipment immediately for physical damage.

+Damaged equipment should NEVER be sent directly to us. Please inform the dealer from whom you acquired it immediately as well as the trans- portation company from which you took delivery. Otherwise, all claims for replacement/repair may be rendered invalid.

+If the unit needs to be shipped, please always use the original packaging to avoid damage.

+Never let unsupervised children play with the ULTRACOUSTIC or with its packaging.

+Please dispose of all packaging materials in an environmentally-friendly fashion.

1.1.2 Initial operation

Please make sure that your ULTRACOUSTIC is provided with sufficient ventilation, and never place it on other amplifiers or in the vicinity of a heater to avoid the risk of overheating.

+Before plugging your ULTRACOUSTIC into a power socket, please make sure you have selected the correct voltage:

The fuse retainer near the power cord connector has three triangular markings. Two of these triangles point in opposite directions. Your ULTRACOUSTIC is set up for the voltage indicated near these markings, and can be altered by turning the fuse mount by 180 degrees. ATTENTION: This does not apply to export models built for 120 V, for example!

+If you use your ULTRACOUSTIC unit with a different voltage, you must change the fuses accordingly. The correct value of the fuses needed can be found in the section “SPECIFICATIONS”.

+Faulty fuses must be replaced with fuses of appropriate rating, without exception! The correct value of the fuses needed can be found in the section “SPECIFICATIONS”.

Power is delivered via the cable that was delivered with the ULTRACOUSTIC. All mandatory safety precautions have been adhered to.

+Please make sure that all of your equipment is grounded at all times. For your own protection, you should never tamper with the grounding of the cable or the unit itself. The unit shall always be connected to a mains socket outlet with a protective earthing connection.

1.1.3 Online registration

Please, do remember to register your new BEHRINGER equipment right after your purchase by visiting www.behringer.com and kindly read the terms and conditions of our warranty carefully.

Should your BEHRINGER product malfunction, our goal is to have it repaired as quickly as possible. To arrange for warranty service, please contact the retailer from whom the equipment was purchased. Should your BEHRINGER dealer not be located in your vicinity, you may directly contact one of our subsidiaries. Corresponding contact information is included in the original equipment packaging (Global Contact Information/European Contact Information). Should your country not be listed, please contact the distributor nearest you. A list of distributors can be found in the support area of our website (www.behringer.com).

Registering your purchase and equipment with us helps us process your repair claims quicker and more efficiently.

Thank you for your cooperation!

2.CONTROL ELEMENTS AND CONNECTIONS

2.1 Front panel

The ¼" jack connector labeled INSTR(UMENT) is the input of the instrument channel of your ULTRACOUSTIC to connect your acoustic guitar. Use a commercially available mono jack cable. We recommend using a cable with impact sound insulation so as to avoid unpleasant incidences during a rehearsal or concert.

The PHASE switch (not included in ACX450) reverses the instrument channel phase by 180°. Use this function to eliminate feedback problems or phase errors of dual pickup systems.

The GAIN controller is used to determine the volume of the respective channel.

With the TUNER switch (not included in ACX450), you can mute the channel. There is a permanent signal at

the TUNER connector at the rear of the unit. You have the option to connect an external tuner to this jack (e.g. BTR2000, TU100).

When the input signal overdrives the instrument channel, the CLIP LED located in the TUNER switch is on (only in ACX1800). Reduce the input gain with the GAIN controller until the CLIP LED is off. Occasional flashing of the CLIP LED caused by signal peaks is harmless though, as the instrument channel has sufficient headroom.

This is the FBQ EQUALIZER. Each sliding controller controls a specific frequency range. In position 0, the frequency is not adjusted. To boost a frequency range, move the respective sliding controller up. To lower its volume, move the sliding controller down. The maximum boosting or damping range is 12 dB.

Press the FBQ switch to activate the FBQ function. While the FBQ is switched off, the controller LEDs are lit with the same brightness. When the FBQ is on and you play your instrument, the LED’s brightness varies, depending on the energy content of the associated frequency range. This visual feature supports you in adjusting the sound and eliminating feedback. The equalizer is always activated, irrespective of whether the FBQ function is on.

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2. CONTROL ELEMENTS AND CONNECTIONS