OPERATING / SERVICE MANUAL RE 27REALTIME EQUALIZERQUICK STARTIf you are familiar with real time analyzers and graphic equalizers, feel free to jump right in. To avoid some of thelurking sharks read these few tips as a reminder of what it is you already know:1. FLAT IS NOT BEAUTIFUL. Equalizers have two basic purposes: correction and enhancement. The Rane analyzerallows you to accurately correct system response to each location. A task very difficult to do by ear. Once this is quicklydone, then you adjust for further sound quality enhancement by ear; only rarely will a system be left in a “flat” condition.2. USE MORE THAN ONE TEST MICROPHONE LOCATION. Speaker dispersion characteristics vary greatly, frombeamy highs to boomy bass traps. While performing the pink noise test, try at least two different test mic locations andaverage the two if they differ.3. USE ENOUGH PINK NOISE VOLUME TO OVERRIDE BACKGROUND NOISE. There’s no need to rundeafening pink noise levels to EQ a system. Just be sure that no green/red LED responds when pink noise is turned off (ifthey do, background noise is causing erroneous readings and pink noise should be turned up higher).4. USE ±3 dB DISPLAY SETTING FOR LOW FREQUENCY ADJUSTMENTS. The crest factor (peak response) oftrue pink noise causes considerable LED flutter in the ±l dB mode, making it difficult to adjust quickly. We recommendthat the ±1 dB setting be used on frequencies below 500 Hz or so; use ±1 dB on the more sensitive mids and highs.5. THE ANALYZER SECTION CAN BE USED WITH ANY OTHER EQUALIZER. The analyzer section of the RE27 responds to whatever the microphone picks up. Simply run pink noise through the desired equalizer (channel) andspeaker and use the Rane analyzer to adjust that particular EQ. The RTA is a completely separate instrument.6. MONITORING -PROGRAM WITH ANALYZER DISPLAY. When the front panel microphone is unplugged, theanalyzer display automatically monitors the output of the equalizer section. Use this feature to identify specific feedbackpoints by watching for red LEDs during the performance. You can then apply EQ exactly where it’s needed very quickly.If all else fails, read the rest of the manual.OPERATING INSTRUCTIONSSince the RE 27 features a unique form of realtime analyzer, we highly recommend that you read this section beforeperforming an alignment with pink noise. If you’ve never used an analyzer before, use these instructions on your firstoccasion. You’ll be delighted at how simple it really is.1. SYSTEM HOOK-UP: Connect the RE 27 into your system as shown on page 6 or 7, whichever is appropriate. Plugthe Rane condenser microphone into the front panel RTA MIC INPUT. CAUTION: Do not plug any other microphone intothe front panel jack: This jack contains DC voltage which may be damaging to other microphones. For special applicationsyou can use another microphone by patching into a send/receive loop on a mixer as described in Rane Note 104 (available onrequest).2. BACKGROUND NOISE CHECK: Any background noises such as air conditioners, talking, nearby traffic and thelike can cause false readings on the analyzer display if the pink noise volume through the speakers is not loud enough todrown these noises out. Before turning on the Pink Noise, turn up the RTA LEVEL control on the RE 27 until some of thegreen and red LEDs respond on the display: now you’re looking at background noise. Slowly turn the RTA LEVEL controlback counter-clockwise until all the green and red LEDs are off, and no background noise is showing on the display. Youwill now have to run the pink noise volume through the speakers loud enough to make sure that the RTA LEVEL control isnot turned clockwise (up) from this setting, otherwise the background noise will falsify the readings.continued on page 4...