www.radialeng.com ® True to the Music PowerPre ™ 500 Microphone Preamp 500 Series Module User Guide ® True to the Music www.radialeng.com Radial Engineering Ltd. 1588 Kebet Way, Port Coquitlam British Columbia, Canada, V3C 5M5 tel: 604-942-1001 • fax: 604-942-1010 email: info@radialeng.
Radial® PowerPre™ 500 User Guide Table of Contents ........................................................Page Feature Set .................................................................... 1 Overview ........................................................................ 2 Getting Started ............................................................... 4 Specifications ................................................................. 8 Block Diagram .......................................................
® True to the Music FEATURE SET 1. GAIN VU - 10 Segment LED bar provides visual peak signal status by simulating the natural ballistics of a VU meter. Single floating LED with peak hold lowers power demand for greater efficiency. 1 2. -15dB PAD - Expands the PowerPre’s capabilities by allowing ultra hot signals from devices such as digital keyboards or electronic drums to be interfaced without distortion. 3. 180º - Polarity reverse used to phase-align two microphones or as a creative element when recording.
® True to the Music OVERVIEW The Radial PowerPre is a state of the art microphone preamp that is designed to make exquisitely detailed recordings quick and easy. You plug your mic in, adjust the level, set the voicing and hit record. Over 18 months in development and a multitude of revisions were invested in making the PowerPre this simple to use. But don’t let the simplicity fool you… the PowerPre will easily outperform others that can cost much more.
® True to the Music In either case you are not actually controlling the gain, only the input sensitivity. Herein lies the problem: Preamps that employ an input attenuator are basically running ‘full’ all the time. In other words, their signal-to-noise ratio is fixed. So when the ‘volume control’ (read attenuator) is turned all the way up, you enjoy maximum performance. But as you reduce the input sensitivity by ‘turning down the volume’ you are actually increasing the amount of noise in the recording.
® True to the Music GETTING STARTED Before making any connections, start by turning off your audio system and turning all volume levels down. This helps protect equipment from turn-on transients that could damage loudspeakers and other sensitive equipment. We recommend using a power bar with an onoff switch as this makes it easy to turn on and off the 500 series rack, monitors and so on, using a single switch.
® True to the Music Set the -15dB pad to the out position as this will likely not be required. The PowerPre has plenty of dynamic range and is very quiet. Unlike most preamps that run ‘full on’ using a variable input attenuator to control the level (and deliver a fixed noise level), the PowerPre is equipped with our unique AccuState™ drive circuit that sets the input gain and the attenuation so that noise is automatically kept at a minimum. This makes it super easy to set the signal chain for lowest noise.
® True to the Music High Pass Filter World class engineers always think in terms ‘layers’ when they record. In other words, they will position the bass in the lower octaves, guitars in the mid-range and cymbals in the upper registers. This allows each instrument to cut through the mix without overwhelming the others. To help focus the instruments, the PowerPre is equipped with a high-pass filter that gently rolls off bass frequencies below 100Hz.
® True to the Music Grounding When you connect an AC powered device like a keyboard to the PowerPre, you can occasionally run into noise problems known as ground loops. This is generally caused by a conflict between the electrical ground and the audio ground. The PowerPre solves the problem by incorporating a ground lift switch that lifts the pin-1 audio ground at the XLR input. You will need to pull the module out of the rack to change the ground switch setting.
® True to the Music RADIAL POWERPRE 500 SPECIFICATIONS* Microphone Input Circuit Type: Microphone Input: Current Draw: Frequency Response: Input Impedance: Mic Preamp Gain: Maximum Gain: Maximum Output: Output Impedance: Output Type: Common Mode Rejection (CMRR): Equivalent Input Noise (EIN): Dynamic Range: Total Harmonic Distortion (THD+N): Intermodulation Distortion (IMD): 100% discrete, transformer coupled output Accustate input fully variable gain control 130mA (maximum draw) 20Hz ~ 20KHz +0dB/-1dB 2
9 +48V_IN INPUT 3 4 2 REAR PANEL GND LIFT OMNIPORT 1 XLR INPUT FRONT PANEL XLR INPUT REAR PANEL NC Radial Engineering Ltd. NO + - R97 6.81K - + SWITCH RING GROUND CONVERTER SENSOR R98 6.81K NO NC NO NC OMNIPORT 2 1 UNBALANCED TO BALANCED 2 1 NO NC PHANTOM +48V BLOCK DIAGRAM C C + - PAD INPUT SWITCH PHASE TRUE PREAMP GAIN VARIABLE FILTER HIGH PASS SWITCHABLE BUFFER & OUTPUT FILTER BREATH PUNCH & 221R BUSS METER BUFFER OUTPUT 4.
THREE YEAR TRANSFERABLE LIMITED WARRANTY RADIAL ENGINEERING LTD. (“Radial”) warrants this product to be free from defects in material and workmanship and will remedy any such defects free of charge according to the terms of this warranty. Radial will repair or replace (at its option) any defective component(s) of this product (excluding finish and wear and tear on components under normal use) for a period of three (3) years from the original date of purchase.
