Wattwerx Little Dragon Maintenance Manual - John Keats, Endymion

Summary of Little Dragon

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    Hugh’s wattwerx little dragon b user/maintenance manual use what works!.

  • Page 2: John Keats, Endymion

    From hugh to you thank you for trusting my amplifier to be a part of this most important part of your life: your music! I build amplifiers for my own use, and hence, put the best of myself into every unit. I part with them, reluctantly, in order to share with others the joy that their design, constr...

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    Little dragon table of contents section one: operations input.......................................................................................................................................8 high boost...............................................................................................

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    Page 4.

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    Page 1 warnings and precautions this device must be properly grounded! Amplifiers generate heat. Do not cover or in any way impede ventilation during operation or a fire and/or serious circuit damage may result. Never remove the amplifier chassis (upper or lower). There are no user-serviceable parts...

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    Page 2 hugh’s wattwerx warrants this product against defects in materials and workmanship for one (1) year from date of original retail purchase (30 days for tubes). Hugh’s wattwerx reserves the right, before having any obligation under this limited warranty, to inspect the damaged product, and all ...

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    Page 3 specifications input impedance: 1 megohm output impedance: 16 ohms preamp tubes: one 12ax7, one ef86, one 12at7 power tubes: two el34 high voltage: 440 volts filament heaters: 6.3v a/c output power: 40w rms into 16 ohms operation voltage 115v a/c 60hz internal speaker: nos british made celest...

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    Page 4 portability, simplicity, power, and tone…these were the design criteria for little dragon. Bruce lee (the little dragon), whose chinese name was jun fan (李振藩 in traditional chinese characters), was an actor, martial arts teacher, philosopher, film director, and screenwriter. The philosophy an...

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    Page 5 the phase inverter is a well-established ltp (long-tail-pair) configuration, and the power section includes a bypassable master volume control, for those who prefer to emphasize preamp distortion. By default, the master volume is completely removed from the circuit, since most connoisseurs of...

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    Page 6 1. After unpacking your new amplifier, save the box and packing material in case you even need to ship your amplifier for any reason. 2. Connect the a/c power cable only to a properly grounded, 3-hole electrical receptacle. 3. When connecting an external speaker, be sure to use an unshielded ...

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    Page 7 quick start instructions no time/patience to read this manual? At least read this page thoroughly before you begin! Before connecting the power cord: inspect the entire amp for signs of damage. If anything appears amiss, do not use the amp. Contact the manufacturer, seller, or shipping compan...

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    Page 8 front panel controls, switches, and jacks input in the interest of simplicity and compactness, little dragon has only one input. This is configured to correspond to the high-sensitivity input on most double-input amplifiers (which is the only one most players usually use anyway). If your guit...

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    Page 9 low boost the low boost switch functions by attenuating the upper frequencies, thereby making the low frequencies more prominent. Engaging the low boost will actually reduce the overall loudness of the output—this is shown in the following graph. For a more bass-heavy tone, you would normally...

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    Page 10 volume (with boost switch) although this control is labeled ‘volume’ for clarity, its functionality is more complex than merely adjusting how loud the amp sounds. This control governs how hot a signal is sent to the second preamp stage (the ef86), and consequently, the texture of the resulta...

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    Page 11 middle (pull bypass) the little dragon middle control is fully segregated from the bass and treble controls, and can be individually bypassed without affecting the other two tone controls. The midrange circuit produces a sharp bump at around 450hz when maximized, and a deep notch (scoop) at ...

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    Page 12 tone stacks, and a nearly flat frequency response with bass and treble controls set at their middle (5) position. The treble control’s response is shown graphically in the following illustration: bass (pull bypass) like the treble control just described, the bass control is implemented as a ...

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    Page 13 rear panel controls, switches, and jacks s peaker 16-o hms hugh’s wattwerx www .W attwerx .C om p entode t riode m aster p ull t o e ngage p resence p ull b ypass s/n: ld-0001 u se w hat w orks 12ax7 ef86 12at7 el34 el34 master (pull to engage) most tone aficionados eschew master volumes in ...

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    Page 14 because our perception of loudness is nonlinear; which is to say that the output of a fifty-watt amplifier is not heard as half as loud as that of a one-hundred watt amplifier. Perhaps a more noticeable effect of this switch is the more tactile feel of the amplifier in the triode position. I...

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    Page 15 bottom chassis components hugh’s wattwerx www .W attwerx .C om 4a s lo b low s tandby o perate o ff o n 120v s/n: ld-0001 overview in order to minimize extraneous hum, all power supply components are isolated from the signal path in a separate chassis. These two segregated units are connecte...

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    Page 16 standby switch to the left of the mains fuse holder is the standby toggle switch. Like the power switch, the downward position puts the amp in the ‘standby’ state (heater filaments are active, but d/c power is not). When turning the amp on, it is advisable to begin with both switches in the ...