User manual RANE AC 24

[. . . ] OPERATORS MANUAL AC 24 ACTIVE CROSSOVER LOW 63 50 40 80 100 125 160 200 250 315 MID 400 315 250 200 500 630 800 HI-MID 4-WAY 3. 15 2. 5 1. 6 4. 0 5. 0 6. 3 8. 0 10. 0 12. 5 HIGH 4 HORN EQ 4 LOW 63 50 40 80 100 125 160 200 250 315 MID 400 315 250 200 500 630 800 HI-MID 4-WAY 3. 15 2. 5 1. 6 4. 0 5. 0 6. 3 8. 0 10. 0 12. 5 HIGH 4 HORN EQ 4 1. 0k 1. 25k Hz 1. 6k 2. 0 1. 0k 1. 25k Hz 1. 6k 2. 0 CHANNEL MUTE 31. 5 A 0 DELAY 10 ms Hz MUTE 160 MUTE 1. 25 kHz MUTE 2 kHz 8 2 kHz 8 CHANNEL MUTE 31. 5 FREQ FREQ FREQ 4-WAY HI-MID FREQ HIGH B 0 DELAY 10 ms Hz MUTE 160 MUTE 1. 25 kHz MUTE 2 kHz 8 2 kHz 8 FREQ FREQ FREQ 4-WAY HI-MID FREQ HIGH 0 DELAY 10 ms 0 DELAY 10 ms 0 DELAY 10 ms 4-WAY 0 DELAY 10 ms 0 DELAY 10 ms 0 DELAY 10 ms 4-WAY AC 24 4-WAY CROSSOVER INPUT OL -64 LIMIT 0 LINK -64 LIMIT 0 -64 LIMIT 0 -64 LIMIT 0 M A S T E R S L A V E INPUT OL -64 LIMIT 0 LINK -64 LIMIT 0 -64 LIMIT 0 -64 LIMIT 0 0 LEVEL 10 0 LEVEL 10 0 LEVEL 10 0 LEVEL 10 0 LEVEL 10 MONO LOW STEREO LINK 0 LEVEL 10 0 LEVEL 10 0 LEVEL 10 0 LEVEL 10 0 LEVEL 10 POWER QUICK START The AC 24 is fully balanced with XLR connectors wired pin 2 "hot" per AES standards. Set the 3-WAY/4-WAY switch on the rear appropriately. When in 3-WAY mode, the HI-MID controls are inactive. The MID / HI-MID Frequency control becomes the MID / HIGH Frequency control. [. . . ] Important Note: The horizontal location of a driver is determined by the front of the voice coil. Identify the driver that is the furthest away from the front of the stack. The horizontal displacement of all other drivers is measured relative to this driver. Take the distance, measured in inches, for each driver and divide by 13. 57. This gives the delay in milliseconds and pot rotation in "fractional-dots. " See Figure 4. Fig. 2 In-Phase Axis Response Without Signal Delay Signal Delay Adjustment Method Two OK, so you want to do this the hard way. The following example outlines one method for Signal Delay alignment of the system in Figure 4. The procedure easily adapts to other configurations. Required tools: Realtime Analyzer Cautions/considerations: With 4th-order filters, it's important to accurately identify crossover frequency settings before adjusting delay. A reference level must be set for each driver at each crossover point. This eliminates errors due to non-flat driver response and room acoustics. When using a 1/3-octave realtime analyzer, best results are achieved if crossover points are set to the nearest 1/3-octave center. Leave FREQUENCY controls as set in Step One. Set Input and Output LEVEL controls to unity (the mark between the 8th and 9th dots). Set all rear INVERT switches to the out (non-inverting) position (assuming all drivers are in phase). Connect Pink Noise output to Crossover Input. Connect AC 24 Sum Output to RTA Line Input. Adjust crossover frequencies to ISO centers: a. For this crossover frequency calibration you are looking at the line level Sum output and NOT the acoustic output. i) The 1st 6 dB red LED on the RTA indicates the Low / Mid crossover frequency. ii) Adjust the LOW / MID Frequency to just light the 1st ­6 dB red LED closest to the desired crossover frequency. Fig. 3 Corrected In-Phase Axis Response with Delay on Low Driver Signal Delay Adjustment Method One If you can not get your hands on the equipment necessary to electronically align the system, it is possible to set the delays using only the horizontal displacement of the sound sources. [. . . ] We highly recommend installing the included security cover As Soon As Possible! Figure 5. Setting Output Levels with a calibrated mic. STEP FIVE: Setting Limiters Each AC 24 Crossover Output has a Limiter. Each Limiter has an independent Threshold control with a range of 0 dB FS to ­64 dB FS. [. . . ]