5F8 “High Power” Twin
TOPOLOGY
Four independent high sensitivity inputs. Three 12AY7 gain stages. The third stage is configured as a cathode follower which drives a classic tweed era tone stack featuring independent Treble and Bass controls with local negative feedback. One 12AX7 recovery stage. Global negative feedback with Presence control. 12AX7 cathodyne phase inverter. Two 6L6 power tubes with fixed bias. Two 12″ speakers.
DESCRIPTION
Fender offered two versions of the Twin during the late 50’s: the 5E8-A and the 5F8. At first glance they might appear to be minor variants of the same model, but they were in fact completely different designs.
The 5F8 version has come to be known as the “high power” or “big box” Twin by modern collectors. Its defining feature being four 5881 output tubes producing ~80 watts of power. But the use of a blackface style tone stack and a long tailed pair phase inverter made the amp more mid-scooped with a tighter, more aggressive sound in overdrive. The 5F8 circuit is in fact nearly identical to the 5F6-A Bassman… except for those four 5881 power tubes putting out 80 watts of thundering goodness. So, if you ever felt like your tweed Bassman was a little weak and anemic, this is your ticket right here.
BASE CONFIGURATION
Weber 12A125 speakers, Mercury Magnetics transformers, Jupiter Yellow capacitors, carbon composition resistors.
Base Price $1800
OPTIONS
Speakers
- WGS G12Q -$70
- Weber 12A150-A +$200
- Celestion Blue +$240
- Your choice TBD
Transformers
- Heyboer output transformer and choke -$70
Capacitors
- Mallory 150 -$50
- Jupiter Red +$60
Cabinet
- Aged Lacquer Finish +$95