The Kay Musical Instrument Company roots go way back to 1890, when the Groeschel Company of Chicago started building bowl-back mandolins. In 1918, the Groeschel name was changed to the Stromberg-Voisenet Company, and incorporated in 1921. C.G. Stromberg was the vice-president, and the company started to produce guitars and banjos under the Mayflower trademark. Henry Kay Kuhrmeyer offered to use his middle name on the instruments, and Kay Kraft was born. Kuhrmeyer bought the company in 1928, and changed the name of the company to Kay Musical Instruments in 1931. At this time they started to mass-produce stringed instruments. At this point the company became a "house brand" company.
Early guitar amplification for the Stromberg company (before Kay) is thought to go way back to 1928. Electric amplification was just being explored and the quest for portable amplification was under development in the mid 1920s. The first Stromberg amplifier is thought to have a 12 in. Jensen speaker driven by old tubes (71A power tubes), and put out 3W. These amps were very basic and little is known about them.
When the economy rebounded in the mid-1930s, Kay (previously Stromberg), went back to developing a guitar amplifier. The depression had halted this research, but many advances had come to surface by 1939. When lap steels and electric guitars became popular and newer technology became available, Kay started to produce amplifiers again. In 1940, Sears, Roebuck, and Company placed its first order with Kay, signifying its entry into supplying large distributors. The first line of Kay amplifiers was introduced in 1952 and they produced tube amps consistently through 1962. In 1962, a new line of amps was introduced with transitorized chassis. The company was sold to Sydney Katz in 1955. B 1965, the guitar market was super-saturated and Kay was feeling the pinch of too much supply with not enough demand. Katz sold the company to Seeburg, a large jukebox manufacture in Chicago. They owned the company for two years and sold to Valco guitars. Kay wanted to buy Valco but Bob Keyworth suggested the opposite; that they sell to Valco. Like many guitar manufacturers of this era, Kay fizzled towards the end of the 1960s, and Kay (and Valco) were out of business by 1970. However, the Kay name did not go away forever. The brand has been reintroduced several times since 1970 and all instruments and amplifiers are currently built in Asia. Kay produces one practice guitar the GA20K (MSR $80) and one practice bass amp GB12K (MSR $120). Kay history and model information courtesy: Michael Wright, Guitar Stories: Volume 2.
Amplifiers currently produced in Asia. Distributed in the U.S. by the Kay Guitar Company in Newport Beach, CA. Amplifiers previously in Chicago, IL between the 1930s and the 1960s.

KAY Guitar Amplifiers Models

KAY F475 HIGH FIDELITY AMP Image

KAY F475 HIGH FIDELITY AMP

- wattage unknown, 1-12 in. speaker, guitar combo, five tube chassis, rear control panel, two inputs, two knobs (v, tone), mahogany cabinet with a curly maple front finished in sunburst, 14.5 in. wide, 18.5 in. tall, 8.25 in. deep, mfg. 194...

KAY K503 HOT-LINE SPECIAL Image

KAY K503 HOT-LINE SPECIAL

- ~4W, 1-8 in. speaker, three-tube chassis, two channels, rear control panel, three inputs, two knobs (v, tone), two-tone brown covering, brown grille with swirls, refridgerator-style handle, 15.375 in. wide, 12.5 in. tall, mfg. 1957-1961.

KAY K750 BUDGET LEADER Image

KAY K750 BUDGET LEADER

- ~5W, 1-8 in. speaker, guitar combo, solid-state chassis, single channel, front silver control panel, three inputs, two knobs (v, tone), black covering, gray grille, 16.25 in. wide, 16.375 in. tall, 6.5 in. deep, mfg. 1966-68.

KAY K700 VANGUARD Image

KAY K700 VANGUARD

- wattage unknown, 1-8 in. speaker, solid-state chassis (four transistors, two diodes), single channel, top control panel, three inputs, two knobs (v, tone), two-tone brown/cream covering, brown grille, mfg. 1962-65.

KAY K504 VIBRATO LEADER Image

KAY K504 VIBRATO LEADER

- ~5W, 1-8 in. speaker, four-tube chassis, two channels, vibrato, rear control panel, three inputs, four knobs (v, tone, s, i), footswitch jack, two-tone brown covering, brown grille with swirls, refridgerator-style handle, 17.25 in. wide,...

KAY K752 VALUE LEADER Image

KAY K752 VALUE LEADER

- 5W, 1-8 in. speaker, guitar combo, solid-state chassis, single channel, front silver and black control panel, three inputs, two knobs (v, tone), black covering, gray grille, 17 in. wide, 14 in. tall, 7 in. deep, mfg. 1966-68.

KAY K300 Image

KAY K300

- ~5W, 1-8 in. speaker, guitar combo, three tube chassis, single channel, rear control panel, two inputs, single volume knob, two-tone brown covering, light brown grille, mfg. 1952-56.

KAY K703 VALUE LEADER Image

KAY K703 VALUE LEADER

- 4W, 1-8 in. speaker, three tube chassis, preamp: 1 X 12AU6, power: 1 X 50L6, rectifier: 35Z5, single channel, rear control panel, three inputs, two knobs (v, tone), two-tone brown/cream covering, brown grille, gold metal handle, mfg. 1962...

KAY K600 Image

KAY K600

- 16-20W, 1-12 in. Jensen speaker, guitar combo, seven tube chassis, two channels, rear control panel, three inputs, three knobs (inst. v, mic v, tone), brown covering, dark brown grille with rounded corners, 24 in. wide, 18 in. tall, 10 in...

KAY K505 TWIN EIGHT HI-POWER Image

KAY K505 TWIN EIGHT HI-POWER

- 12W, 2-8 in. speakers, guitar combo, five-tube chassis, preamp: 1 X 12AX7, 1 X 12AU7, power: 2 X 6V6, rectifier: 5Y3, two channels, rear control panel, four inputs, three knobs (v1, v2, tone), two-tone brown covering, brown grille with sw...

KAY K754 TREMOLO Image

KAY K754 TREMOLO

- 5W, 1-8 in. speaker, guitar combo, hybrid chassis with three tubes and one transistor, single channel, front silver and black control panel, three inputs, three knobs (v, tone, s), black covering, gray grille, 18 in. wide, 16 in. tall, 8...

KAY K704 VANGUARD Image

KAY K704 VANGUARD

- 5W, 1-8 in. speaker, solid-state chassis (7 transistors, 4 diodes), single channel, vibrato, top control panel, three inputs, four knobs (v, tone, s, i), two-tone brown/cream covering, brown grille, mfg. 1962-66.

KAY K705 VANGUARD Image

KAY K705 VANGUARD

- 10W, 1-10 in. speaker, solid-state chassis (7 transistors, 4 diodes), single channel, vibrato, top control panel, four inputs with three tone circuits, four knobs (v, tone, s, i), footswitch jack, two-tone brown/cream covering, brown gril...

KAY K755 TREMOLO Image

KAY K755 TREMOLO

- 10W, 1-8 in. speaker, guitar combo, solid-state chassis (9 transistors, 6 diodes), single channel, front silver and black control panel, three inputs, four knobs (v, tone, s, i), black covering, gray grille, 19 in. wide, 17 in. tall, 9.5...

KAY K506 VIBRATO 12 Image

KAY K506 VIBRATO 12

- 12W, 1-12 in. speaker, guitar combo, six-tube chassis, preamp: 2 X 12AX7, 1 X 12AU7, power: 2 X 6V6, rectifier: 5Y3, two channels, rear control panel, four inputs, five knobs (v1, v2, tone, s, i), two-tone brown covering, brown grille wit...

KAY K615 Image

KAY K615

- 16-20W, 1-15 in. Jensen speaker, guitar combo, seven tube chassis, two channels, rear control panel, three inputs, three knobs (inst. v, mic v, tone), brown covering, dark brown grille with rounded corners, 24 in. wide, 19 in. tall, 10 in...

KAY K706 VANGUARD Image

KAY K706 VANGUARD

- 15W, 1-15 in. speaker, solid-state chassis (8 transistors, 4 diodes), two channels, vibrato, top control panel, four inputs (two per channel), seven knobs (Ch. 1: v, tone, i, Ch. 2: v, tone, i, master vibrato speed control), two footswitc...

KAY K507 TWIN TEN SPECIAL Image

KAY K507 TWIN TEN SPECIAL

- 20W, 2-10 in. speakers, guitar combo, seven-tube chassis, two channels, rear control panel, four inputs, six knobs (Ch. 1: v, tone, Ch. 2: v, t, s, i), two-tone brown covering, brown grille with swirls, refridgerator-style handle, 24 in....

KAY K756 TREMOLO Image

KAY K756 TREMOLO

- 20W, 1-12 in. speaker, guitar combo, solid-state chassis (11 transistors, 6 diodes), two channels, tremolo, front silver control panel, four inputs, six knobs (Ch. 1: v, tone, s, i, Ch. 2: v, tone), black covering, gray grille, 21 in. wid...

KAY K707 GALAXIE I Image

KAY K707 GALAXIE I

- 35W, 1-12 in. speaker, solid-state chassis (11 transistors, 8 diodes), two channels, vibrato, top control panel, six inputs (three per channel), seven knobs (Ch. 1: v, tone, i, Ch. 2: v, tone, i, master vibrato speed control), two footswi...

KAY K515 HEAVY DUTY BASS AMP Image

KAY K515 HEAVY DUTY BASS AMP

- 15W, 1-15 in. speaker, bass combo, seven-tube chassis, preamp: 4 X 12AX7, power: 2 X 6V6, rectifier: 5Y3, two channels, rear control panel, four inputs, six knobs (Ch. 1: v, tone, Ch. 2: v, t, s, i), two-tone brown covering, brown grille...

KAY K760 VALUE LEADER TREMOLO/REVERB Image

KAY K760 VALUE LEADER TREMOLO/REVERB

- 20W, 1-12 in. speaker, guitar combo, solid-state chassis (13 transistors, 6 diodes), two channels, reverb, tremolo, front silver control panel, four inputs, seven knobs (Ch. 1: v, tone, s, i, r, Ch. 2: v, tone), black covering, gray grill...

KAY K520 HEAVY DUTY BASS AMP Image

KAY K520 HEAVY DUTY BASS AMP

- wattage unknown, 1-15 in. speaker, bass combo, five-tube chassis, preamp: 1 X 5879, 1 X 7199, power: 2 X 6L6, rectifier: 5U4, rear control panel, three inputs, two-tone brown covering, brown grille with swirls, refridgerator-style handle,...

KAY K708 GALAXIE II Image

KAY K708 GALAXIE II

- 35W, 1-12 in. speaker, removable chassis guitar piggyback configuration, solid-state chassis (11 transistors, 8 diodes), two channels, vibrato, top control panel, six inputs (three per channel), seven knobs (Ch. 1: v, tone, i, Ch. 2: v, t...

KAY K761 PROFESSIONAL REVERB/TREMOLO Image

KAY K761 PROFESSIONAL REVERB/TREMOLO

- 50W, 2-12 in. speakers, guitar combo, solid-state chassis (17 transistors, 6 diodes), two channels, reverb, tremolo, front silver control panel, four inputs, seven knobs (Ch. 1: v, t, b, s, i, r, Ch. 2: v, t, b), two footswitch jacks, bla...

KAY K550 Image

KAY K550

- 12W, 2-8 in. speakers, guitar combo, five-tube chassis, preamp: 2 X 6EU7, power: 2 X 6V6, rectifier: 5Y3, two channels, reverb, rear control panel, four inputs, four knobs (v1, v2, tone, r), two-tone brown covering, brown grille with swir...

KAY K720 BASS AMPLIFIER Image

KAY K720 BASS AMPLIFIER

- wattage unknown, 1-15 in. speaker, bass combo, solid-state chassis, single channel, rear control panel, three inputs, two knobs (v, tone), two-tone brown/cream covering, brown grille, 27 in. wide, 22 in. tall, 9.5 in. deep, mfg. 1962-66.

KAY K765 PROFESSIONAL PIGGYBACK Image

KAY K765 PROFESSIONAL PIGGYBACK

- 100W, 2-12 in. speakers, guitar piggyback configuration, solid-state chassis (17 transistors, 6 diodes), two channels, reverb, tremolo, front silver control panel, four inputs, seven knobs (Ch. 1: v, t, b, s, i, r, Ch. 2: v, t, b), two fo...

KAY K770 DUAL PURPOSE GUITAR/BASS AMPLIFIER Image

KAY K770 DUAL PURPOSE GUITAR/BASS AMPLIFIER

- 50W, 1-15 in. speaker, guitar and bass combo, solid-state chassis (12 transistors, 4 diodes), two channels (guitar and bass), front silver control panel, four inputs (two per channel), five knobs (Guitar: v, b, t, Bass: v, tone), black co...

KAY K771 VALUE LEADER BASS AMPLIFIER Image

KAY K771 VALUE LEADER BASS AMPLIFIER

- 20W, 1-12 in. speaker, bass combo, solid-state chassis (6 transistors, 4 diodes), single channel, front silver and black control panel, three inputs, two knobs (v, tone), black covering, gray grille, 25 in. wide, 21 in. tall, 9.5 in. deep...