CL44 Four Channel Compressor/Limiter User's Manual VERSION 1.1 PreSonus Limited Warranty PreSonus Audio Electronics Inc. warrants this product to be free of defects in material and workmanship for a period of one year from the date of original retail purchase. This warranty is enforceable only by the original retail purchaser. To be protected by this warranty, the purchaser must complete and return the enclosed warranty card within 14 days of purchase. During the warranty period PreSonus shall, at its sole and absolute option, either repair or replace, free of charge, any product that proves to be defective on inspection by PreSonus or its authorized service representative. To obtain warranty service, the purchaser must first call or write PreSonus at the address and telephone number printed below to obtain a Return Authorization Number and instructions of where to return the unit for service. All inquiries must be accompanied by a description of the problem. All authorized returns must be sent to the PreSonus repair facility postage prepaid, insured and properly package. Proof of purchase must be presented in the form of a bill of sale, canceled check or some other positive proof that the product is in within the warranty period. PreSonus reserves the right to update any unit returned for repair. PreSonus reserves the right to change or improve design of the product at any time without prior notice. This warranty does not cover claims for damage due to abuse, neglect, alteration or attempted repair by unauthorized personnel, and is limited to failures arising during normal use that are due to defects in material or workmanship in the product. Any implied warranties, including implied warranties of merchantability and fitness for a particular purpose, are limited in duration to the length of this limited warranty. Some states do not allow limitations on how long an implied warranty lasts, so the above limitation may not apply to you. In no event will PreSonus be liable for incidental, consequential or other damages resulting from the broach of any express or implied warranty, including , among other things, damage to property, damage based on inconvenience or on loss of use of the product, and, to the extent permitted by law, damages for personal injury. Some states do not allow the exclusion of limitation of incidental or consequential damages, so the above limitation or exclusion may not apply to you. This warranty gives you specific legal rights, and you may also have other rights which vary form state to state. This warranty only applies to products sold and used in the United States of America. For warranty information in all other countries please refer to your local distributor. Limited Warranty Outside of The U.S. PreSonus Audio Electronics produc ts are warranted only in the country where purchased, through the authorized PreSonus distributor in that country, against defects in material and workmanship. The specific period of this limited warranty shall be that which is described to the original retail purchaser by the authorized PreSonus dealer or distributor at the time of purchase. PreSonus does not, however, warrant its products against any and all defects: 1) arising Out of materials or workmanship not provided or furnished by PreSonus, or 2) resulting from abnormal use of the product or use in violation of instructions, or 3) in products repaired or serviced by other than authorized PreSonus repair facilities, or 4) in products with removed or defaced serial numbers, or 5) in components or parts or products expressly warranted by another manufacturer. PreSonus agrees, through the applicable authorized distributor, to repair or replace defects covered by this limited warranty with parts or products of original or improved design, at its option in each respect, if the defective product is shipped prior to the end of the warranty period to the designated authorized PreSonus warranty repair facility in the country where purchased, or to the PreSonus factory in the U.S., in the original packaging or a replacement supplied by PreSonus, with all transportation cost and full insurance paid each way by the purchaser or owner. All remedies and the measure of damages are limited to the above services. It is possible that economic loss or injury to person or property may result from the failure of the product; However, even if PreSonus has been advised of this possibility, this limited warranty does not cover any such consequential or incidental damages. Some states or countries do not allow the limitations or exclusion of incidental or consequential damages, so the above limitation may not apply to you. Any and all warranties, express or implied, arising by law, course of dealing, course of performance, usage of trade, or otherwise, including but not limited to implied warranties of merchantability and fitness for a particular purpose, are limited to a period of two years from either the date of original retail purchase or, in the event no proof of purchase date is available, the date of manufacture. Some states or countries do not allow limitations on how long an implied warranty last, so the above limitations may not apply to you. This limited warranty gives you specific legal rights, and you may also have other rights which vary from state to state, country to country. PreSonus Audio Electronics, Inc. 7257 Florida Blvd. Baton Rouge, LA 70806 225-216-7887 www.presonus.com Table of Contents 1 1.1 1.2 2 2.1 2.2 2.3 2.4 2.5 3 3.1 4 4.1 A 1 2 Overview Introduction Features Controls & Connections Front Panel Basic Layout Compressor & Limiter Controls Bypass & Link Patch Panel Power Basic Setup & Applications Basic Applications Technical Specifications Appendix A word about compression... Troubleshooting 1.1 INTRODUCTION Thank you for purchasing the PreSonus CL44 four channel dynamics processor. This processor was designed using state of the art components to deliver crystal clear compression and limiting for an infinite period of time. We believe that it is an exceptional sounding unit as well as an exceptional value. Feel free to contact us at 1-800-750-0323 anytime for any reason whatsoever. We value your suggestions and your comments! Please pay close attention to how you connect your CL44 to your system. Improper grounding is the most common cause of noise problems found in studio or live sound systems. We urge you to at least scan this manual before hooking up your CL44 to become familiar with its features and various applications. Good luck and enjoy your CL44! 1.2 FEATURES The following is a summary of your CL44's features: Full Featured Compressors/Limiters Each channel of your CL44 contains an audio compressor and limiter. You have broad control over threshold, ratio, attack, and release for each compressor. You can select between auto or manual attack and release curves (refer to the application section of this manual for a quick tutorial on compression and limiting). The compressor will prove to be very useful in many situations such as recording instruments or vocals that vary in loudness. Channel Linking Using the Link function, you can link together two channels of the CL44 for stereo operation. When linked, the processors follow the setting of the linked channel to the left, which becomes the master. When two channels are linked, the sidechains are summed. Separate Bypass and Gain for Each Channel All four channels have a separate bypass for listening to 'before and after' performance tests and a gain control to make up for any output level lost due to compression of the signal. Insert Sidechain on Each Channel Each channel of your CL44 was designed with a special jack for spectral processing, compression keying and ducking applications. Sidechaining is useful for removing annoying sibilance from vocal tracks (de-essing) or automatically ducking tracks behind a narrator for 'auto mixing' a service, broadcast or performance. Optical Mode The CL44 has an optical compressor emulation mode. This feature alters the signal' characteristics to sound like the signal s was processed using a vintage compressor. Compander The CL44 has a compander on each channel. The compander works like an upward expander. Essentially, it increases the level of the signal that is below the threshold according to the percentage specified on the knob. The range is from 0% to 100%. Balanced XLR and Unbalanced 1/4" Tip/Ring/Sleeve Input/Output Your CL44 accepts XLR connectors for balanced or a single 1/4" TRS for unbalanced inputs and outputs. +4dBu or -10dBV Insert Switch The operating level of your CL44' inserts can be switched between +4dBu (pro levels) to -10dBV (consumer levels) for S ease of use with external equipment in any situation. To Get Help Call Us: 1-800-750-0323, 9AM to 5PM, CST Visit our World Wide Web site: http://www.presonus.com Email Us: presonus@presonus.com 2.1 FRONT PANEL BASIC LAYOUT Notice that the front panel is divided into four identical sections. These are the four signal processing channels of the CL44. Each channel contains: Compressor/Limiter Lo Filter Compander Gain (Output Control) Link & Bypass Control Optical and Auto Mode 2.2 COMPRESSOR/LIMITER CONTROLS Lo Filter The setting determined by the lo filter control allows signals passing through/above the selected frequency to be acted upon by the compressor while the frequencies below the selected frequency are rolled off and ignored by the processor. The Lo frequency control is variable from 20 Hz to 12 kHz with the twelve o' clock position being 2 kHz. An example of the Lo filter in use would be to set the cut-off frequency at 4 kHz to reduce annoying sibilance (SSss' in a vocal performance. The s) compressor will de-accentuate the frequencies above the selected 4 kHz while the frequencies below 4 kHz are allowed to pass. Remember, the Lo filter effects the processing, but the audio path remains full range. Threshold The Compressor threshold sets the level at which the onset of compression begins. When the signal is above the threshold setting, it becomes 'eligible' for compression. Turning the threshold knob counter-clockwise causes more of the input signal to become compressed if you have a ratio setting of greater than 1:1. Ratio Ratio sets the compression slope. This can be defined as the output level versus the input level. For example, if you have the ratio set to 2:1, any signal levels above the threshold setting will be compressed at a compression ratio of 2:1. This means that for every l dB of level increase into the compressor, the output will only increase 1/2dB, thus producing a compression gain reduction of 0.5dB. As you increase the ratio, the compressor gradually becomes a limiter. A limiter is defined as a processor that limits the level of a signal to the setting of the threshold. For example, if you have the threshold knob set at 0dB, and the ratio turned fully clockwise, the compressor becomes a limiter at 0dB. This means that the signal will be limited to an output of 0dB regardless of the level of the input signal. Compander The Compander works like an upward expander. Essentially, it increases the level of the signal that is below the threshold according to the percentage specified on the knob. The range is from 0% to 100%. Compander is derived from a combination of the word "compressor" and "expander". The effect a compander circuit achieves is that of restricting the dynamic range of the signal. The compressor prevents the transient of the signal from going above a setting while the expander ensures that the signal is boosted below a predetermined point. This results in the signal being maintained within a very restricted range without the loss of any information. The signal "seems" louder without actually going above the level determined by the compressor. Apparent loudness is the result. The ratio selected for the compressor determines the amount of activity of the expander on the incoming signal. Attack Attack sets the speed at which the compressor 'acts' on the input signal. A slow attack time (fully clockwise) allows the beginning envelope of a signal (commonly referred to as the initial transient) to pass through the compressor uncompressed, whereas a fast attack time (fully counter-clockwise) subjects the signal to the ratio and threshold settings of the compressor more rapidly. The Attack control is only active when the Auto button is not pushed in. When the auto button is pushed in, the compressor automatically determines the appropriate attack time for compression. Release Release sets the length of time the compressor takes to return the gain reduction back to zero (no gain reduction). Very short release times can produce a very choppy or 'jittery' sound, especially in low frequency instruments such as a bass guitar. Very long release times can result in an over compressed sound, sometimes referred to as 'squashing' the sound. All ra ...