5F6A (1959) Tweed Bassman Series

$1,599 - $2,495

Condition: Custom Built


Guitar Version:

Select Speaker Choice


Bass Only Version:
Condition: Custom Built


Our 5F6A TWEED BASSMAN is based upon the original 1959, Bassman® 5F6A amplifier. Many say that this amp design is where it all started and where it all ended! The 5F6A is by far, the most famous tube amplifier of all time. This is the same amp with superimposed modifications that Jim Marshall incorporated into the JTM45, Bluesbreaker and Plexi amps.

We build two versions of the 5F6A amplifier. One version is based on the original 5F6A and is designed for the guitar. Here, the first two preams are joined with a shared 250uf cathode bias capacitor and there are dual input jacks for the normal and bright channels. The second jack on each channel is -3DB's. This is an excellent channel for P9's or any other pickups with high output. Tele's and humbuckers seem to prefer the 1st input jack but also benefit with greater headroom on input #2. Thought the guitar can use either set of input jacks, most prefer the "Bright" channel, with the exception of those seeking low end growl! We increase the power supply filtering to eliminate hum and allow for reserve power in the lower register. We use four "period correct" Jensen P12Q Alnico speakers for the half-stack.

Our "Bass Only" version is customized and specially voiced for the Bass Guitar, though we have still left the "Bright" channel fully functional for the guitar. With this version, we replace the tube rectifier with a solid state rectifier raising the operating voltages and the output power throughout the amplifier. Here, we dramatically increase the power supply filtering to produce a tight low end and provide the reserve current necessary to drive the bass speakers to full output. Wit this version, we split the cathode caps on the first preamp so the Bass preamp has its own voicing and is separated from the guitar input jacks. The bass channel has a 250uf bypass capacitor while the guitar channel utilizes the standard value 25uf capcitor. For the Bass half-stack, we use four Jensen "Punch" Bass 10" speakers with 2" voice coils, each speaker weighing 8.8 lbs and rated at 150 watts for each speaker.

Both versions can be built as a 4 X10" half-stack or special 2 X 10" mini-Bassman for those who desire a smaller cabinet size and less weight. The Classic 5F6A puts out approximately 40 watts while the Bass version puts out 50 watts. Controls are Normal Volume, Bright Volume, Treble, Mid, Bass and Presence. Vintage "chicken-head" knobs are on the deck. Both size cabs are constructed with solid finger jointed pine. The 5F6A Bassman can be ordered in the traditional Tweed with Oxblood grill and Brown Dogbone handle, or you may select any color combination you like from our choice of colors below. As with all FIREBELLY amplifiers, the '59 Bassman is hand built using a vintage fiber tag board with each component hand soldered one component at a time. The tag board is raised above the chassis floor to eliminate vibration and allow for air circulation around the components. Filtering is accomplished with F&T German electrolytic capacitors. The tone caps are Mallory M150 coupling capacitors and silver micas. These amps produces an extraordinary amoung of clean headroom and break-up and compression occur at just the right sweet spot. With the Classic version, because a tube rectifier is used, finger sensitive "sag" is also available. With the customized Bass only version, sag is eliminated through the use of a solid state rectifier and greatly enhanced power supply filtering. The bass version is also designed to provide the maximum amount of clean headroom pushing the compression zone to the top of the volume control. The '59 5F6A Bassman is a powerful tone machine, whether voiced for the Guitar or Bass. The '59 BASSMAN is Dripping with Tone!


Dual Channel, Four Inputs

Class A/B Design, 50-Watts RMS Output

1-12AY7, 2-12AX7, 2-6L6GC's, 1-Solid State Rectifier/Copper Cap, 4 - 10" Combo or 2 - 10" Combo

Four - Jensen Bass "Punch" Ceramic Speakers


One Year Warranty On All Parts And Workmanship

Certificate of Build Authenticity

Operation Manual

72-Hour Burn-In Prior To Shipping!

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Call: ( 310 ) 701-1950

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