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MESA/Boogie circuits that led to the refinement of your new instrument. Feel confident, as we do, that this amp will inspire many hours of musical satisfaction and lasting enjoyment.
PRECAUTIONS & WARNINGS USE COMMON SENSE AND ALWAYS OBSERVE THESE PRECAUTIONS: WARNING: EU: permission from the Supply Authority is needed before connection. WARNING: Vacuum tube amplifiers generate heat. To insure proper ventilation always make certain there is at least four inches (100mm) of space behind the rear of the amplifier cabinet. Keep away from curtains or any flammable objects.
The big daddy F-100 is the power broker of this clan with the undeniable authority of 4x6L6’s working for your tone. This big block bad boy produces stunning clean headroom and can push some serious air in its 2x12 combo format featuring two Celestion Vintage 30’s or, when punishment is required, the Long Chassis head pumping a 4x12…it’s the final word in loud.
OVERVIEW: (Continued) darker than that of its lower power family members but posses a depth and punch found only in amps of this serious-gigging horsepower range. Our legendary 60/100 switch has been included and allows you to detune the power section to achieve the brighter, more clippable feel of the F-Series.
CONTROLS: GAIN: This is by far the most powerful control in each of the three different Modes that are activated by the Mode switch. It not only determines the overall gain amount, shape and sensitivity of the Mode selected...but it is also a powerful Tone control. Generally speaking, whatever is dialed up here ultimately determines the Modes’...
CONTROLS: MID: (Continued) pressed, even feel to the strings and therefore less apparent resistance to the pick. As the MID control is increased, ( 11:00 through 11:30 ), the sound is rounded-out and filled-in with a focused mid attack appearing rather quickly. As you would guess, the feel starts to change - becoming more resistant.
CONTROLS: MASTER: (Continued) -rectly to a mixing board or recorder, this control will determine the amount of signal you will be sending via this jack. In this application it is usually best to start with the MASTER controls set to ( 7:00 ) and gradually increase them to the proper level.
REAR PANEL: REAR VIEW: WARNING: Unplug power before replacing fuse or removing FUSE bolts mounting chassis. POWER FUSE RCORD / PHONES FX SEND 120 V~ STEREO / MONO 60 Hz FOOTSWITCH SOCKET BELOW FUSE: This is the A.C.’s ( Alternating Current ) main fuse and provides protection from outside A.C. fluctuations, 2A S.B.
4x12 cabinets may be 4, 8 or 16 Ohms. If you are not sure of the impedance of your cabinet, you may need to remove the Rear Panel in order to verify the impedance rating of the individual speaker or speakers. Mesa/Boogie 4x12 and 4x10 cabinets come standard wired to 8 Ohms, and are wired in series-parallel.
TUBE NOISE & MICROPHONICS: You may occasionally experience some form of tube noise or microphonics. Certainly no cause for alarm, this quirky behavior comes with the territory and the Tone. Much like changing a light bulb, you don’t need a technician to cure these types of minor user serviceable annoyances and in fact, you’ll be amazed at how easy it is to cure tube problems...by simply swapping out a pre-amp or power tube! First may we suggest that you set the amplifier up on something so that you can get to the tubes comfortably without having to bend...
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DIAGNOSING PREAMP TUBE PROBLEMS: Because your amplifier is an all tube design, it is quite possible that you will at some point experience minor pre-amp tube noise. Rest assured - this is no cause for alarm and you can take care of the problem yourself in a matter of minutes by simply swapping tubes.
into oscillation or start crackling or any other form of bizzare noise, it is considered normal and functional. BIAS ADJUSTMENT: (a continuing series) NOTE: An article written by Randall Smith that we thought you might find interesting. Here’s a question we often hear: “Why doesn’t Mesa put bias adjustments in their amplifiers?”...
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it doesn’t need to be adjustable.” BIAS ADJUSTMENT: (Continued) When you set the bias (whether it’s by selecting the right resistors, as we do, or adjusting a trimmer — which is quicker) what you are doing is establishing the correct amount of idle CURRENT that flows through the power tubes.
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How much money and trouble that has saved Mesa/Boogie players you couldn’t estimate. Our rigorously tested and hand selected tubes are available at your nearest Mesa/Boogie Pro Center or from us directly. Nobody offers better price, quality or warranty than we do ... so why swerve? Next time we’ll talk about our part in developing the great Sylvania STR 415 type 6 6 and how we’re on the verge of seeing something...
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SPEAKER IMPEDANCE MATCHING & HOOK-UP GUIDE: IMPEDANCE: Wiring up speakers to provide the most effective load and making sure that all of them are in phase will help in creating the best sound possible. This is not too difficult, as long as you understand a few things about loading and how to connect your speakers to provide an optimal resistive load.
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SPEAKER IMPEDANCE MATCHING & HOOK-UP GUIDE: (Continued) PARALLEL: When wiring in parallel, the resistance of the speakers decreases. Two 8 ohm speakers wired in ( hooked-up ) Parallel results in a 4 ohm load. It’s easy to calculate the effect of a resistive load when all the speakers are all the same resistance. It is really not suggested to wire different resistive load values in Parallel ( 8 and 4, 16 and 8 etc.
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WIRING SCHEMES...Amplifier to Speaker Cabinets Partial back view of amplifier Partial back view of amplifier 8 OHM 4 OHM 4 OHM 8 OHM 4 OHM 4 OHM 8 Ohm Cabinet Partial back view of some Mesa amp 8 OHM 4 OHM 4 OHM 4 Ohm Cabinet 8 Ohm Cabinet...
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WIRING SCHEMES...Amplifier to Speaker Cabinets Partial back view of amplifier Partial back view of amplifier 4 OHM 4 OHM 8 OHM 8 OHM 4 OHM 4 OHM 8 Ohm Cabinet 16 Ohm Cabinet 8 Ohm Cabinet 8 Ohm Cabinet SAFE MISMATCH CORRECT MATCH Partial back view of amplifier Partial back view of amplifier...
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WIRING SCHEMES...Amplifier to Speaker Cabinets Partial back view of amplifier 16 Ohm 4 OHM 4 OHM 8 OHM SERIES BOX 8 Ohm 8 Ohm 8 Ohm Cabinet 8 Ohm Cabinet 8 Ohm Cabinet SAFE MISMATCH Partial back view of amp Partial back view of amplifier CORRECT MATCH 8 OHM...
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WIRING SCHEMES...Amplifier to Speaker Cabinets Partial back view of amplifier 16 Ohm 4 OHM 4 OHM 8 OHM SERIES BOX 8 Ohm 8 Ohm 8 Ohm Cabinet 8 Ohm Cabinet 16 Ohm Cabinet SAFE MISMATCH Partial back view of amplifier 8 OHM 4 OHM 4 OHM...
ON TRIODES, PENTODES & IRISHMEN: With apologies to Friends and Relatives from the Emerald Isle - who will make their appearance soon enough - the humor which follows is dedicated to the memories of Spec McAuliff and Fae (Rafael) McNally, two of the True Greats. As their numerical references suggest, the terms Diode, Triode and Pentode indicate the number of elements within the vacuum tube i.e.
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the plate, electrons will flow only during the times when the plate is positively charged. During periods of negative plate charge, ON TRIODES, PENTODES & IRISHMEN: (Continued) electron flow is stopped and the space charge of electrons remains com- pressed in the area around the cathode. Thus a diode tube - one with a cathode and an anode - is mostly used to rectify alternating current into direct current by passing it without restriction, but in one direction only.
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grid, they discover...there’s almost nothing there. The path they’re on has them aligned to zing straight through the spaces BETWEEN ON TRIODES, PENTODES & IRISHMEN: (Continued) screen grid windings. So rather than a close and personal encounter, they just fly on past - and once they’re out that far, there’s no stopping them. The influence of the plate takes over and - being solid metal and of the highest positive attraction - it is at this final destination that the electrons congregate.