User manual NADY CL-5000

[. . . ] CL-5000 DUAL CHANNEL COMPRESSOR LIMITER WITH GATE OWNER'S MANUAL DUAL CHANNEL COMPRESSOR LIMITER WITH GATE CL-5000 Congratulations! You have just purchased on of the finest professional compressor limiters on the market today. This unit was developed using the expertise of professional sound engineers and working musicians. You will find your new NADY AUDIO CL-5000 has superior performance and greater flexibility than any other compressor in its price range. Thank you for selecting NADY AUDIO Date of Purchase Dealer's Name City State Zip Model# Serial # Features · · · · · · · · · Two independent compressor/limiter/gates in a road-tough steel single-rack-space (1U) housing Utilizes a unique circuitry which combines hard and soft knee compression styles, thus providing excellent inaudible and music program compression as well as providing creative and effective dynamics processing Advanced operating features include fully automatic or manually variable attack/release times, compression ratio, and threshold control Dual 12 stage gain reduction and 8 stage input/output metering Dual-mono or stereo operation; servo-balanced inputs (with automatic hum and noise reduction) and outputs Built-in adjustable dynamic enhancer (selectively replaces high-end loss during even severe compression brought on by high-energy low-end content) IRC (Interactive Ratio Control) expander/gate (which automatically adjusts expansion per the program material, thus eliminating the noise floor during quiet sections or music pauses) TRS side-chain applications, including de-essing, emphasizing/de-emphasizing certain instruments during recording, eliminating feedback in live applications, and ducking Shielded internal power supply and voltage selector for switching between ~115VAC (60 Hz)/~230VAC/(50Hz) An equilateral triangle enclosing a lightning flash/arrowhead symbol is intended to alert the user to the presence of uninsulated "dangerous voltage" within the product's enclosure, which may be of sufficient magnitude to constitute a risk of electric shock. [. . . ] The extent of the resulting dynamic level is dependent on the threshold, attack, release and ratio settings. As it is the desired effect of a compressor to increase a low level signal, generally the threshold is set low. The "inaudible" compression mode requires fast attack and release times and low ratios. The fastest the chosen control times and the higher the compression ratio, the greater the effect on the short-term dynamics. This fact is often used to achieve audible and creative sound effects. Leveling The leveling mode is used to keep output level constant, i. e. to compensate for long term gain changes, without affecting the short -term dynamics. Normally, the threshold is set quite low in order to be able to increase low -level signals. Leveling requires slow attack and release times, combined with a high ratio. Because of the very slow response time, leveling has no effect on signal peaks or short-term changes in average level. Limiting The limiting function requires a fast attack time and a high ratio and release time setting, which is dependent on the specific use and the desired sound effect. As it is usually the task of a limiter to limit only high signal peaks, the threshold is usually set at a high level. The dynamics are reduced dependent on the ratio setting and the degree by which the threshold point was exceeded. If the attack time is adjusted to control only the average level without affecting signal peaks above the threshold, this is referred to as the program limiter. If the attack time is further reduced in order to also control signal peaks, this is defined as a peak limiter. Clipping In contrast to the two previously mentioned limiters, the clipping mode features infinitely fast control times, an infinite compression ratio and creates an unsurpassable barrier ("brickwall") for all signals above a certain level. To be able to control the signal peaks, the clipping function radically cuts signals above the threshold, without affecting the amplitude of the original signal. If used in normal applications, this function remains inaudible and under certain circumstances it can even lead to an improved sound, because cutting the transients creates artificial harmonics. If misused, clipping can cause very obvious and distasteful distortion, which when taken to the extreme, will convert the signal's waveform into a square wave signal. This effect is often produced in guitar distortion devices ("fuzz boxes"). 11 2. EXPANDER/GATE SECTION The main task of the Expander/Gate is to "inaudibly" eliminate undesirable background noise from the usable signal. This assumes that there is a slight level difference between the usable signal and noise floor, in order to be able to define the operating threshold of the Expander/Gate. At the same time, the Expander/Gate must respond very quickly (have a very fast attack time) so that the signal's leading edge remains unaltered. Because the Expander/Gate of the CL-5000 is self-adapting to the program material, it will be possible to obtain more satisfactory results with the new IRC (Interactive Ratio Control) circuit than with conventional expanders. When expansion occurs there are no common side effects due to the extremely smooth and unobtrusive action of the circuit. [. . . ] This is generally accomplished by turning up the system gain to purposely induce feedback, searching for the center frequency of the feedback and then equalizing at that frequency to remove the feedback. Once this feedback has been attenuated, the system gain is again increased to induce another feedback point and the whole procedure is repeated until the engineer is satisfied that the relevant problem frequencies have been corrected. In spite of this equalizing process, feedback remains a difficult problem. Often enough, acoustic changes occur as the audience enters the room, which again leads to feedback problems. [. . . ]