Joye Jam started in the Spring of 2000 out of a growing interest in guitar and vacuum tube audio equipment by Colin D. Joye, a music, electronics and hifi audio fan. Joye Jam specializes in prototype and unusual or artistic audio hifi and music equipment. Most of the equipment was produced only once, but can be recreated without having to design from scratch. The parts cost estimates are what it could cost to aquire the parts necessary to construct these. Additional labor costs are estimates and may vary by 50%. Shipping is extra and depends on your area. All models here are somewhat customizable, especially the Plasma tweeters, as they have been very popular. Look for a line of guitar pedals to come out sometime too, including a waveshaper which uses non-linear amplification (does anyone have a pair of LH0094 exponent / rooting ICs?), a versital clipper, an echo pedal, phasor (FM) / vibrato (AM), a selectible-bit digitizer and a few other weird ideas. Also watch for the computerized dynamic speaker matrix to appear in a few years. Email me for questions or other info if you would like to have a model constructed.
The LM12Z is a mono amplifier capable of delivering 130 watts RMS into a 4-ohm load. The output stage is based on the LM12 high-power op-amp. The LM12Z has ons high-impedance input, one low-impedance input, a main volume, a fine volume, a line output, and a five-band equalizer. The 2 output jacks are selectable to be in either series or parallel for maximum flexibility. There is a circuit ground selector switch and a cooling fan as well. The front and back faces of this amp are blue-purple plexiglass with gold old-English lettering on the front. Total parts cost was about $180. Estimated labor cost: ~$150. This amp was designed to be used with the Bass Guitar Box, BGB215, below.
The BGB215 is a Bass Guitar Box which uses two aluminum-
cone 15" woofers in a 2.8-cubic foot 5/8" particle board box.
The box is carpeted with black carpet and has 8 black plastic
corners. The front mounting board is blue-purple, like the amp.
The box has one 1/4" jack in the back and a 9"x16"x3" pocket in
the lower back of the box.
Total parts cost was about $150, including speakers. Estimated labor cost: ~$70.
The QubeTube is a very portable high-quality guitar
amp which incorporates a small 3-tube 5-Watt amplifier. The box
is shaped like a cube (9¼"x9¼"x9¼") and uses a high
quality Jensen AlNiCo reissue 8", 25 Watt speaker, the "P8R". The
amplifier uses a 12AX7 preamp tube, a 50L6 octal output tube and a
35W4 rectifier tube. The Qube Tube has a volume control, tone
control, high- and low-impedance inputs, and a low-impedance output
(currently not connected on S/N 001). The covering for the box is a vintage-style
yellow tweed with a vintage-style black/silver/white grill cloth
and small brass corner guards.
Total parts cost was about $200. Estimated labor cost: ~$80.
The Bean Pole is a tall, skinny multi-driver lead guitar
amp for tight spaces (dorm rooms?). It stands over 5' tall, and is just
4.5" wide (foot print is 8"x8"). It uses ten 2"x3" oval, 3-watt TV
speakers connected to a 32-watt amp. The amp has a volume and tone
control along with one input and uses the TDA2050 32-watt amplifier
chip. The volume control will also have a power switch on it, and
the "power on" indicator will be a blue LED. The Bean Pole will be
finished probably with neon green paint, black grill cloth and silver
plexiglass panels for the input and controls.
Total parts cost: ~$60, Estimated labor cost: ~$60.
The Bull Frog is a very compact horn-loaded bass guitar
amp for small spaces and portability (dooms, apartments, etc.). Its
dimensions will be about 6" wide, 29" tall and 18" deep. It will
use two high-excursion 5", 50-watt woofers and an LM12-driven amplifier
featuring a volume control. The finish will be pewter-colored carpet,
silver/white/black vintage-style grill cloth. The two woofers sit
inside a small 0.15cu.ft. enclosure from which a folded horn is ducted.
The horn opens to a 5.5x11" opening in the front. Total power is ~150
Total parts cost: ~$100 , Estimated labor cost: ~$80 .
The Greenback212 get its name from the two 12"
Celestion G12M "Greenback 12's" it has squeezed into the 26"
tall, 15" wide cabinet. The Greenbacks are 16-ohms each wired
in parallel and handle 50 watts combined. The box is Dynamatted
and has foam corner-, and panel-traps inside to help dampen
resonance. The box is carpeted with thick burgundy-colored
carpet with a black/silver/white vintage-style grill cloth on
the front and chrome corner guards. The sound is very clear and
dynamic, and projects extremely well in a large room.
Total parts cost was approximately $220. Estimated labor cost: ~$80.
This box is currently being powered by a modified Dynaco Mark IV 25 Watt mono tube amplifier which uses EL34's for the main output stage and a 7199 tube on the preamp. The guitar signal is preamplified by a small Fisher mono preamp, the PR-6. This amp has been modified as well to include a smaller-value output capacitor for less muddy bass, a volume control, an output limiter for smooth distorion and 1/4" inputs and outputs. The preamp tube is a 6SC7 metal octal tube. The sound output level is astonishingly loud for such a small amplifier. The distortion is very mellow and crunchy.
The Vibrotube is a stand-alone vibrato unit which
uses tubes for the oscillation, preamping and rectifying. It
has controls for vibrato depth (actually tremolo, but "Tremtube"
didn't sound quite appealing) and speed as well as gain. The
circuit was adopted from the Vox AC-30 vacuum tube vibrato
circuitry, which uses two 12AX7's, a 12AU7, and a 5Y3. I may
try using the cheaper 5687 black-plate triodes in the oscillator
and modulator cicuitry instead of the 12AX7 and 12AU7.
Total estimated parts cost is around $100. Estimated labor cost: ~$70.
The Arcturus BlueTone preamp idea has its roots in
the antique vacuum tube electronics era. Arcturus, a vacuum
tube manufacturer of the 1920's and 30's, created vacuum tubes,
like the 124 triodes, for example,
fashioned out of blue-colored glass for a very unique look. I
will be constructing a preamp out of these 124
triodes in the creation of this artistic guitar
preamp, but the tubes are very rare, expensive and old. Finding
a replacement tube may be very difficult, but for the extremely
unique vintage looks, the rarity of the tubes is set aside.
Only high quality new or NOS vintage-style parts will be used in
this preamp, such as cloth-covered wire and power cord and maybe
a wooden or gold-plated steel base or case. These preamps
are like a Lamborghini: Each one will have its own "personality".
Total expected parts cost is ~$350. Estimated labor cost: ~$100 (~$250 for a quilt wood polished case).
The Plasmatone-RG1 is a pair of extremely dynamic
plasma tweeters (see Plasma tweeters II).
Each tweeter has a high-power transmitter oscillator which drives a tesla
coil to produce a small plasma flame. Frequency range is ~3kHz up to
~40kHz at up to ~108dB. The current producing the flame is
modulated by an audio signal, producing sound with perfect
transient response, no coloration and no Doppler distortion.
The high-impedance input to the tweeters is amplified by a
12AX7 dual triode. There are controls for varying the volume,
crossover point and flame size. The steel-cage electronics
boxes are 10"x6"x5.27" and the Faraday cages surrounding
the tweeter anodes are approximately 3" in diameter.
Total parts cost was around $700 / pair. Estimated labor cost: ~$300.
Like the Plasmatone-RG1, the Plasmatone-RG2 is a
plasma tweeter designed for the artistically minded. It will utilize
one main control and power supply chassis and two satellite tweeters.
The motif is a short, wide chassis with tall capacitors and vacuum tubes.
Total parts cost is estimated around $800 / pair. Estimated labor cost: ~$400.