CUTTING EDGE 2101 Superior Ave. Cleveland, Ohio Phone: + (216) Fax : +(216)

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1 CUTTING EDGE 2101 Superior Ave. Cleveland, Ohio Phone: + (216) Fax : +(216) "VIGILANTE" INSTALLATION, OPERATION & USER GUIDE JULY 1988 DIAL DOMINANCE! The quest of every competitive, aggressive and successful Broadcaster. In an effort to assist the Broadcaster in obtaining that DIAL DOMINANT sound over the air, CUTTING EDGE TECHNOLOGIES introduces the "VIGILANTE" limiter. This unit actually began its life as an APHEX DOMINATOR, but through the design and circuit modifications provided by CUTTING EDGE, the ability of this unit improves dramatically! The "VIGILANTE" is currently the secret audio processing device used by the leading stations in New York, Los Angeles, Philadelphia, Detroit, Miami, Baltimore, and Cleveland. The "VIGILANTE" has also won the competitive loudness wars with Orban Optimods, CRL, Modified Texar Processors, and the infamous Gregg Labs Multiband limiter. If installed properly, it can assist you in creating DIAL DOMINANCE within your market! The differences between this unit and a stock APHEX DOMINATOR are: different cross-over frequencies for both the low end as well as the high end, selectable attack and release times for each audio band, user adjustable limiting threshold levels for each band. The use of these features will be discussed later in this guide. What follows here is an easy to use "Operation & User Guide" that supplements the APHEX manual. Please read this guide thoroughly so that proper understanding of the limiter along with correct installation and setup can be performed. INSTALLATION The VIGILANTE Limiter can be ordered and operated in one of two configurations. The basic limiter, which consists of the multiband limiting circuitry only, or the VIGILANTE-PLUS which consists of the multiband limiting circuitry and the optional Clipper/15 KHZ Filter Card. With the basic VIGILANTE limiter unit, the installation must be between a preprocessor and the preemphasis circuit of an Optimod 8100 processor. In this mode, the VIGILANTE provides the limiting functions while the Optimod provides the FM pre-emphasis and clipping/filtering needed for stereo broadcasting. The VIGILANTE-PLUS is installed between a preprocessor and a stereo generator of your choice. The only requirement is that the stereo generator must have a FLAT input. That means that any pre-emphasis or low-pass filter circuitry must be bypassed or removed. Most stereo generators provide this as a selectable option within the units. All pre-emphasis, loudness clipping, and low-pass filtering is provided within the VIGILANTE-PLUS circuitry. In either setup, the VIGILANTE is installed between a pre- processor and either an Optimod, or stereo

2 generator. The pre- processor can be a wideband device such as a Compellor, or it can be multiband like TEXAR AUDIO PRISMS. The preprocessor should act more as a leveling device than a compressor. The idea is to keep consistent dynamic levels working into the limiter. By doing this, the limiter will operate within its "sweet-spot" more often, and produce a more consistent over the air sound. The recommendation here is to use multiband preprocessing. The reasoning is that multiband preprocessors assist with creating "spectral consistency" for the following limiting device. Consistent sounding "tonal" balance is what should be perceived when auditioning this type of system over the air. Any multiband processor that is used with the VIGILANTE should be set for a flat response through that unit. This will allow the VIGILANTE to tailor the over the air sound. (for TEXAR users, set the output of the HIGH band 2-3 db lower than the rest of the unit) What follows are the instructions for installing the VIGILANTE with either an Optimod, or any stereo generator. INSTALLATION WITH AN OPTIMOD 8100 As it was mentioned earlier, the VIGILANTE can be electrically installed between a preprocessor and the Optimod. Once this has been done, much of the Optimod will need to be set in the "BYPASS" mode, and some circuitry will be defeated. The gain control circuitry should be put in the "BYPASS" or "PROOF" mode. To accomplish this, turn the switch on Card #5 of the Optimod to the "PROOF" mode. This turns OFF the gain control circuits. The "Proof/Operate" switch on Card #6 must be left in the "OPERATE" position. If it is placed in the "PROOF" mode, then the clipping in the Optimod will be defeated. Due to the method of high frequency limiting in the VIGILANTE limiter, the High Frequency limiter in the Optimod must be defeated. To do this, remove Card #6 from the Optimod, locate the two IC'S marked IC- 607 and IC-612. Remove these IC'S, this defeats the High Frequency limiter. Replace Card #6 into the Optimod. Store these IC'S in a safe place. Set the input pots on Cards #3 & #4 to the 12:00 or halfway position. This completes the installation preparation on the Optimod. INSTALLATION WITH A STEREO GENERATOR Setting up the unit for use with a stereo generator is much simpler to perform. Electrically install the VIGILANTE between the preprocessor and the stereo generator so that the output of the VIGILANTE is wired to the input of the stereo generator. Make sure that the optional de-emphasis in the VIGILANTE is off. To check this, remove the top panel on the VIGILANTE, locate the clipper/filter circuit board, it is the board that is "piggy- backed" on top of the main board. In the middle of the "piggy- backed" board is a "dip" socket with jumpers in it. Make sure that they are in the two outmost jumper locations. These should line up with the "BYPASS" markings on the board. This indicates that the optional output de-emphasis circuitry has been bypassed. Restore the top panel, wire the VIGILANTE to the input of the stereo generator. As it was mentioned before, make sure the stereo generator has a FLAT input. All pre-emphasis and low-pass filtering defeated. If it not done so on your stereo generator, or you are not sure, refer to your manual for assistance. This completes installation with a stereo generator. The OUTPUT CEILING control on the VIGILANTE will be used to set modulation into the stereo generator. The one other possible installation that is possible, is the use of the VIGILANTE-PLUS with the Clipper/Filter option that would operate into the stereo generator input of an Optimod To accomplish this, switch the selector on the back of the Optimod to the test position. This selects the RCA

3 jacks on the back of the Optimod for direct input to the stereo generator. This also "lifts" the outputs of the Optimod's processing circuitry. Connect the output of the VIGILANTE to the RCA jacks. Remember that this is an unbalanced input, so you will need to set the switches on the back of the VIGILANTE for unbalanced output operation. This completes installation for use with an Optimod stereo generator. SETUP & OPERATION With all the units set into place and the power ON, it is time to setup and operate the system. The first stage to setup is the preprocessor, this device should be set for more leveling action than compression. If a compressor is all that is available for use, set the unit to operate as a slow AGC device rather than a "pumping and wheezing" compressor. Now let us turn our attention to the settings on the VIGILANTE, set the cross-over switches to the 100 HZ position for the low end cross-over, and 6000 HZ for the high end cross-over. Next we will set the ATTACK and RELEASE time constants. Set the switches in the following positions to start with: ATTACK RELEASE Low Band: S S Mid Band: M M High Band: M F The release pot should be set to the "3 o'clock" position. These settings are for starting out with and can be experimented with later. The Threshold levels are the last item to be set. One of the designed features of this unit is the use of different threshold levels for limiting within each band. This allows the unit to perform the proper amount of limiting within each audio band as it is "deemed" necessary. The high frequency band uses the most amount of limiting, and the low frequency band uses the least. By doing this, the high frequencies can be "tightly" processed for use with pre-emphasised clipping, and the low end can operate in a more "looser" fashion and allow good low end transient feel to "blast" through the system. The Threshold levels are set with the 10 turn dial pots that have the "clock" pointer indicators on them. When the pots are set counter-clockwise, the limiting threshold is at its highest. This would allow more audio peak information to pass along to the clipping in the Optimod. As the pots are "dialed" clockwise, the threshold is lowered and limiting, or more limiting is performed. This would reduce the amount of audio that would reach the clippers. To start with, the limiting thresholds should be set at the following: DIAL SETTING RECOMMENDED Low Band: Mid Band: High Band: Again, these settings can or should be adjusted to the requirements of format, or "tonal" signature of the over the air sound. The remaining switches should be in the following positions:

4 PROCESS: OFF STEREO TRACKING: OFF OUTPUT CEILING: AS NEEDED RANGE: AS NEEDED TEC ON The PROCESS switch is always left in the OFF position, this defeats the APHEX clippers. If this switch is turned on, then too much clipping will be performed. The TEC circuit is described in the manual as a "Transient Enhancement Circuit", this circuit provides a small amount of dynamic expansion to the operation of the limiter. The effect is a bit more definition, but it is also minimal and not always noticeable. The DRIVE control on the VIGILANTE should be set as to provide anywhere from 6-8 DB of limiting indicated on the LED Bar graph. This finishes the initial setup of the VIGILANTE. The last phase of setup is the amount of clipping to be performed. Due to the two possible installation configurations of the VIGILANTE, there are two possible clipping procedures. Both of which are explained here: CLIPPING SETUP & ADJUSTMENT WITH AN OPTIMOD INSTALLATION In this configuration, the clipping will actually be taking place in the Optimod. To set the clipping, set the rotary test switch on the Optimod front panel to either the left or right "FILTER OUT" position. This is the output of the Optimods clipper filter section. Proper amounts of clipping will be indicated when the meter peaks anywhere from -2 to 0 on the VU meter. To set this level, use the detented OUTPUT CEILING pot on the VIGILANTE to set the level. You may have to set the RANGE button in the LOW or HI position to get your level within your operating range. Once you have completed this, the CEILING LEVEL control then becomes your "clipper drive" control. When setting or changing the amount of clipping, just use this control, it will allow you to change the amount of clipping in precise 1 db increments. CLIPPING SETUP & ADJUSTMENT WITH "VIGILANTE-PLUS" OPTION In this setup, the "loudness" clipping is performed within the VIGILANTE Limiter. The clipping is "factory set" at a recommended setting when the unit is received, but adjustment can be performed as follows. Located on the front panel is a pot labeled "CLIPPING", this is a screw driver adjustment that will allow the clipping to be increased or decreased by 5 db. The reference mark on the front panel is the recommended setting. The adjustment range is +/- 5 db up or down from this mark. Setting of the clipping drive should be done subjectively and over a period of time. Try the unit with the recommended setting and work from there. If adjustment is needed, make the adjustment, listen awhile, evaluate, and then continue to adjust or leave it be. Your ears will be the judge. That completes clipping setup and adjustment for the VIGILANTE-PLUS option. Now it is time for the "Kool-Aid Acid Test! Put it ON THE AIR! The over the air sound should be competitively loud, yet "open" enough to minimize fatigue. The high end should be "bright", and the low end should be warm, rich, and at times may appear deep. Should the high end end appear to sound too "brittle" lower the threshold level of the high band by turning the threshold pot clockwise. Start with half-turns and experiment from there. Should one of the bands appear too dull, release more of that band to the clippers by raising the threshold, to do this turn the pot for

5 that band in a counter-clockwise direction. If the limiter sounds as if it is operating too fast, slow down the band that sounds too dense. If the whole unit sounds too dense, reduce the master release time pot by turning it counter- clockwise. Start with 1/4 turns and work from there. This will "relax" the overall sound of the station. If the overall sound still sounds too dense or a bit distorted, reduce the clipping. If more loudness is warranted try increasing the limiter's drive pot, or increase the amount of clipping. Remember added clipping brings listener fatigue...be careful! If you have gotten this far and you are happy with the sound, then we have achieved our goal of DIAL DOMINANCE! If not, then please pick up the telephone and dial the number that is listed on the front of this guide. When someone answers, keep yelling at them until you are satisfied! Be careful they might yell back! Only kidding! We thank you for your interest in the CUTTING EDGE TECHNOLOGIES "VIGILANTE" limiter. If you are pleased with this product, we think that you will be pleased with the next few CUTTING EDGE products that will be appearing within the not-to- distant future! Now it is time to file this "User Guide" away and allow yourself to get involved with some other project while your station DIAL DOMINATES the market!