Manual Model 9844 Vacuum Tube Microphone Preamplifier
GoldMike Manual By Hermann Gier and Wolfgang Aichholz Version 1.4 - 5/2000 The information in this document has been carefully verified and is assumed to be correct. However Sound Performance Lab (SPL) reserves the right to modify the product described in this manual at any time. Changes without notice. This document is the property of SPL and may not be copied or reproduced in any manner, in part or full without the authorisation of SPL.
Foreword .................................................................................................. 3 Introduction ............................................................................................ 4 Hookup ..................................................................................................... 5 Installation & Connections ................................................................. 5 Power Supply ...........................................................................
Introduction The GoldMike is another jewel in the SPL Tube series. Like all SPL tube processors, the GoldMike combines the unique sonic qualities of tube technology with state-of-the-art manufacturing, meticulous component selection and high-tech conception. This latest product, a dual-channel tube microphone preamplifier with superb sonic qualities, is particularly suited for recording vocals and acoustic instruments.
Carefully select a place for setting up the GoldMike. The unit should be situated away from heat sources and direct sunlight. Avoid installing your GoldMike in environments exposed to vibrations, dust, heat, cold or moisture. Keep the unit away from transformers or motors or any other unit that could generate large variations in power supply or cause electrical interferences. Do not install the unit in close proximity to power amplifiers or digital processors.
The following graph shows the correct wiring for connecting unbalanced signals to the balanced XLR connectors. VERY IMPORTANT Phantom power must be switched off before unbalanced signals are connected! Otherwise short circuits cause damages! Power Supply A stable, low ripple torroidal power supply is the foundation for any high-fidelity sound shaping. 6 Built around a torroidal transformer, the power supply allows for a minimal electromagnetic field with no hum or mechanical noise.
Advantages of the SPL dual-stage preamplifier The GoldMike's engine is the newly designed SPL dual-stage preamplifier. During the first stage of amplification the signal is amplified by a semi-conductor circuit while the second stage applies tube electronics. We achieve a high common-mode-rejection by using laser trimmed components. Likewise, minimal noise and distortion figures distinguish our high-quality preamp.
Tech Talk Sound optimization already during recording: FLAIR circuitry The FLAIR circuitry enhances the presence of vocals and acoustic instruments, FLAIR makes these elements cut better through a mix. It has proved to be superior in double-blind tests. Once a signal completes the semi-conductor amplification stage, it is then split and fed into the tube stage and the FLAIR electronics. The FLAIR circuitry enhances a signal's presence and cutting ability.
Control elements 7 1 2 3 4 5 6 The MIC GAIN knob controls the input signal's amplification. The range extends to 72 dB of gain.The levels should be adjusted for a meter reading around 0 VU to get the best signal-to-noise performance. Please note that the meters show only an rms/average level, so keep your GoldMike from pegging the meters' needles.
REVERSE 3 Tips on how to use the phase reverse By pressing the REVERSE button, you invert the microphone's polarity.When the REVERSE button is released (status LED off ) the signal is in phase. Pressing it switches the signal out-of-phase (LED on). Reasons for reversing the phase: 1. You are recording a vocal or voice-over and the vocalist cannot hear him or herself very well in the headphones.
True to SPL's philosophy, the GoldMike features the sound enhancing FLAIR circuitry. More than simply a frequency-range manipulating tool, the FLAIR circuitry is also a timebase shifting (phase) device that enhances a sound's harmonic content. The close relation between frequency- and amplitude-timebase and the source signal's dynamics remains intact. FLAIR boosts the frequency range from 1.5 kHz to 20 kHz. The center frequency, set at 6 kHz, is boosted 2.
Audio Specifications Frequency Response:...................................... 10 Hz - 100 kHz, +/- 0.5 dB Common-Mode-Rejection at -20 dBu:...... 1 kHz: -80 dBu ... 10 kHz: -73 dBu Harmonic Distortion Input level Gain THD -30 dB ................................... 30 dB ................... 0.175 % -60 dB ................................... 60 dB ................... 0.2 % Signal-To-Noise Ratio Signal-to -Noise ratio: Gain 72 dBu 60 dBu 30 dBu A-weighted -62.4 dBu -71.8 dBu -85.6 dBu Dynamic Range: .....
SPL electronics GmbH (hereafter called SPL) products are warranted only in the country where purchased, through the authorized SPL distributor in that country, against defects in material or workmanship. The specific period of this limited warranty shall be that which is described to the original retail purchaser by the authorized SPL dealer or distributor at the time of purchase.
