1961 Gibson Discoverer Tremolo (GA-8T)

For your consideration, Garrett Park Guitars presents this 1961 Gibson Discoverer Tremolo (GA-8T), a compact Kalamazoo-era tube combo with the original tan covering. This tremolo-equipped variant of Gibson’s GA-8 line is prized for its harmonically rich breakup and dynamic, musical character—the kind of small-format tube amp that sits perfectly in a studio, on a small stage, or in a vintage collection.

Following a recent service, which included replacing some electrolytic capacitors to ensure reliable operation, this amp is lively and immediate—very responsive to pick attack and dynamic playing. Its onboard tremolo (an amplitude-modulation effect built into the amp’s circuitry) provides a warm, pulsing movement that complements clean passages and helps shape a vocal-like tremolo at the sweet spot of breakup.

The cabinet retains the early tan covering with minor age-appropriate wear, but no egregious rips or structural issues. The only truly notable blemish is the broken grille badge (a missing "G" is unfortunately common among Gibson amps from this period). The chassis, controls, and transformers are in good working order following the service work. The original Jensen speaker (included) was replaced some time ago with a JBL, which delivers such a musical voice and extra low-end presence that we elected to leave it in place. Aside from the speaker swap and the recent cap job, the amp is largely as found and performs beautifully.

This 1961 Discoverer Tremolo is a sweet find for a player wanting a compact, characterful vintage tube amp with on-board tremolo — or for a collector seeking an attractive, early-covering Gibson combo that has been sensibly serviced and set up.

Specifications

Model & Year

• Model: Gibson Discoverer Tremolo (GA-8T)

• Year of Manufacture: 1961

• Serial Number: 10286

Chassis & Electronics

• Circuitry (GA-8 family): SIngle-preamp tube design with a single-ended / parallel small-power output

• Tubes:

  • Preamp: 12AX7

  • Power & Phase Inverter: 6BM8 (x2)

  • Rectifier: 5Y3

• Transformers: Original

• Controls: Volume, Tone, Depth, Frequency

Speaker & Cabinet

• Speaker: JBL (replacement)—original Jensen speaker included in sale 

• Cabinet / Covering: Early tan Tolex-style; cabinet shows only light wear consistent with age; no repairs or structural issues

Cosmetic Condition

• Overall: Very good—clean and attractive for display or regular use; most notable blemish is broken Gibson badge

• Notable wear: Minor scuffs and edge-wear consistent with vintage

Playability & Tone

• Tone: Warm, harmonically rich cleans with pleasing breakup when pushed; the amp’s small-power single/parallel topology yields musical breakup at low volumes. The onboard tremolo adds a classic vintage pulse that is musical and not overly mechanical. 

• Responsiveness: Very touch sensitive—responds well to dynamics and pick/finger attack.

Accessories

• Footswitch: Included

• Power Cord: Original 2-prong