Manley DUAL MONO Owner's Manual

Contents

Manley DUAL MONO Owner's Manual Manual pdf 8 page image

OPERATIONAL NOTES8SWITCHING ONAllow this unit a few minutes for the tubes to warm up before use. It is not recommended that youleave your preamplifier permanently switched on. This only wastes electricity and tube life. Yourpreamplifier has solid state rectification and reaches peak operating condition in approximately 30minutes.TUBE LIFEAs with all tubes, their quality degrades with age. This is due to cathode emission, a natural processfound in all tubes. We recommend that you have your preamplifier checked every 4-5 years,depending on usage, usually the preamplifier will require re-tubing after this time has elapsed.Increased noise is usually a sign that the tubes need replacing.OPERATIONThe Microphone Preamplifier is equipped with a switchable 48 Volt phantom supply. Pull thetoggle to turn phantom power on or off. You should only turn phantom power on once you have a solidstate(FET) condensor mic plugged in and patched through to the Mic Pre and the monitor volume is waydown or off. DO NOT use phantom with an unbalanced cable, unbalanced output mic, or valuable ribbonmics. Damage to the Mic or preamp may result. Do not change mics or mic patches with phantom poweron especially if the monitors are up. See page 6.The 40 dB Microphone Preamplifier is equipped with five preset GAINs, 40, 45, 50, 55 and 60 dB.These "numbers" are only if the ATTENUATE control is turned to full. The GAIN control is not a pad.The input attenuator is kinda like a pad. GAIN sets the amount of negative feedback used in the Mic Pre.These preset gains affect tonal quality, noise and linearity characteristics. At lower gains (40 dB setting)the Pre Amp has a very clean quality, in some ways like solid state and is the best at minimizing tube hiss.50 is a "normal" setting because it tends to sound most like the source, and is very musical and real. Thelower settings can sound slightly slower, further back and more mellow by comparison. The 60 dB settinguses almost no feedback and can give a slightly more punchy and forward or aggressive sound. It may bea little "hot" (more than simply warm) for some tastes. Experiment to discover your own descriptions. Youwill likely find a few settings that you prefer for your style of music.The INPUT ATTENUATE controls the amount of signal entering the amplifier circuit. Use thiscontrol to adjust the level of the input signal. It has no effect on the tonal quality and simply sets the levelsent to tape. Use the tape machine's meters to optimise levels.The PHASE SWITCH can reverse the polarity of the mic signal. The middle position is used forthe 1/4" DIRECT INPUT and de-selects the mic input transformer. Reversing the polarity or phase is oftenneeded when two or more mics are picking up the same source. For example it would be needed when onemics the top and bottom of a snare - one skin is going towards one mic and the other skin is going awayfrom the other mic. If one signal is not "reversed" then you lose lows. Polarity reverse can also help withsome vocal / mic / headphone situations because " somewhere " the polarity flipped one too many times.It happens. General advise - try it each way - listen, with vocals always ask the singer which way they prefer.The headphones may "cancel" with the sound they hear in their skull while singing.