Few amplifier circuits have shaped the sound of modern guitar like the 5F8-A. Designed by Leo Fender in 1959, this circuit was the pinnacle of Fender’s Tweed era, offering rich, dynamic cleans, tight low-end response, and harmonically complex overdrive when pushed. It became the foundation for Marshall’s first big amps and has influenced countless boutique builders ever since.
The Amwatts Keef is a faithful replica of this legendary circuit, housed in a tweed-covered 2x12” combo with premium components. Running at 80-100 watts RMS, it provides huge clean headroom, a bold, open sound, and natural tube-driven overdrive when pushed. Whether you're looking for sweet, articulate cleans or thick, dynamic crunch, this amp delivers in every setting.
At low volumes, the Keef offers warm, three-dimensional cleans with a tight low-end and balanced mids—perfect for jazz, blues, rock, and country. Crank it up, and you get that legendary Tweed breakup, with a rich, dynamic overdrive that remains articulate, no matter the gain level. The long-tail phase inverter helps retain clarity even when fully saturated, making it one of the most expressive amps ever designed.
This is the circuit that Marshall famously copied in the late ‘60s, helping define the sound of British rock and blues. It’s no wonder players like Keith Richards, Neil Young, Eric Clapton, and countless others have relied on amps like this to shape their tone.
We at PG love classic circuits that stand the test of time, and the Keef is a perfect example. Whether you’re after pristine cleans, touch-sensitive breakup, or thick, vintage overdrive, this amp delivers the best of the Tweed era with uncompromising authenticity.
Features:
Model: The Keef
Circuit: 5F8-A Replica
Configuration: Tweed Covered Combo – 2 x 12"
Cabinet: Solid A-Grade Void-Free Pine, Tweed Covering, Nitro Lacquer Sealed
Channels: 2 – Hi/Lo Inputs for Each
Controls: Normal/Bright Volume Controls - Treble, Middle, Bass Tone Controls
PPIMV Master Volume (Underneath Chassis)
Speakers: 2 x Weber 12F150 – 50W
Transformers: Mercury Magnetics – Custom
Preamp: 2 x 12AY7, 1 x 12AX7
Phase Inverter: Long Tail
Power Tubes: 4 x 5881 / 4 x 6L6GC / 4 x KT66
Rectifier: GZ34
Output Power: 80-100W RMS – Fixed Bias
