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Site still under
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Where
amplifiers are built to a standard not a price point.
Amplifiers:
1. Standby switch instead
of ground switch—allows filaments to pre-heat, which prolongs tube life.
2. Three-prong
grounded, long power cord—be safe—it doesn’t affect your tone.
3. Screen Grid resistors: 470 ohm, 2 watt resistors help protect the power tubes by preventing excess
current flow within the tubes (and potential thermal runaway).
4. Choke
instead of the 5K ohm power resistor: improves tone and feel of the amp, especially
for rhythm work.
Chassis:
Weber high quality 16ga sheet steel, extra fine buffing, heavy nickel and
chrome plating
Cabinet: Mojo Covered in Brown Tweed &
Oxblood with Striped Grill Cloth, (H) 16" x (W) 20" x (D) 9
1/2". Made just like the originals
with 3/4” finger-jointed solid Pine.
Speaker: Vintage Jensen P12Q for full mojo. Or a
Weber 12A125A, replica of Chicago Jensen P12Q and other medium power AlNiCo
12's.
Specs: size=12", 11oz AlNiCo magnet, 30
watts, 1-1/4" voice coil, curved seam, ribbed cone. Woody, reedy, early 60's Fender tone. Tight
low end, detailed high end. Compressed and fattened at higher volumes. The
Weber is recommended for gigging.
Circuit board material is
electrical grade fiberglass or fiberglass laminate with hollow tubular turrents
used for component mounting. Point to
point wiring used throughout entire amplifier.
Wire:
Mil Spec 600V, 200C Teflon insulated multi-strand hook-up wire is used
in place of solid core cloth covered wire. (Occasionally a small piece or two
of cloth wire will be used to
maintain
Coax:
RG-174 low noise coax used as required.
Hoffman grounding scheme implemented: Input
jacks are isolated from the chassis to minimize stray ground
loops. The pot shells
are ground via a bus wire connected to the jacks/preamp ground point.
Lead Dress: Yes my lead dress does
not follow some of the “picture perfect” examples where all wires are
bent at 90 degree
angles etc. I prefer “function over form.” Lead lengths are kept to a minimum, while
keeping
wires a proper
distance away from each other and any components which could lead to hum, noise
or parasitic
oscillations.
Capacitors:
Sprague Orange Drop or Mallory 150 series
coupling caps
Sprague Atom power supply caps
Resistors:
Metal film, 1% resistors, (quiet, least drift)
Carbon Film or Carbon Composition
resistors used if desired to maintain that 50’s crackle.
Potentiometers: Alpha or CTS pots
Switchcraft jacks
Carling switches
Ceramic tube sockets
Keps or nylon insert nuts—no parts to vibrate
loose!
V1 – 12AY7
V3, V4 – 6V6
Note: all
wattages are approximate