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Wal D-Mag
E-mu Drumulator
E-mu Emax
Roland VP-330.
Korg SQ-10 Sequencer


Tone Bender

From 1965 to approx. 1968…


Which is the true Tone Bender?


When we say Tone Bender we can’t speak only for a single fuzz box, we are speaking about an invention started in mid 1965 and get lots of evolution through time. Different versions made from ’65 to ’68 like:


Sola Sound Tone Bender MKI,

Sola Sound Tone Bender MKI.V,

Sola Sound Tone Bender Professional MKII,

Vox Tone Bender Professional MKII,

Marshall Supa Fuzz,

RotoSound Fuzz Box,


and finally in 1968 Sola Sound Tone Bender MKIII,IV, Tone Bender Fuzz which are belonging more in the modern fuzz history as they are not so rare, like the first Tone Bender boxes, and the tone also changed to more crunchy, the midrange got brighter and there is nowhere the depth of the old bassy fuzzes.


Sola Sound Tone Bender MKI


History of the Tone Bender MKI


All began in 1965 when Vic Flick (lead guitarist of The John Barry Seven & Orchestra who perform the legendary soundtrack: "The James Bond Theme") brought a Gibson Maestro Fuzz-tone to electronic engineer Gary Steward Hurst, asking him to increase the sustain of FZ-1. Hurst came with the idea of the first Tone Bender MKI which was available to the public by Macari brothers' Musical Exchange shops. It was housed in a gold Hammerite paint in a steel-wooden enclosure. The first Tone Benders sold as Gary Hurst design units and after a very few time labeled with small letters Sola Sound Ltd in very small, descried letters.

Tone Bender MKI



Technology of the Tone Bender MKI


Speaking more technically, MKI is a tree transistor circuit (with no doubt the father of MKII), using a Mullard OC75 and two 2G381 germanium transistors. Based on FZ-1, MKI made its success by increasing the input voltage from 3V (that FZ-1 was using) to 9V and simply decrease the amount of certain resistor to increase sustain. The board of the circuit is just fiber board only to mount the components as they are wire directly from one component to the other. Also, shielded cables were used to reduce noise and rejection rate and true bypass switch was used for the first time.




Tone Bender MKI circuit





Famous Users of the Tone Bender MKI


            Some of the famous users of the MKI were: Pete Townshed of the Who, Jeff Beck of the Yardbirds, Mick Ronson and the Beatles.


Sola Sound Tone Bender MKI.V


History of the Tone Bender MKI.V



In early 1966 Tone Bender changes in a more stable and quality fuzz box. The steel box replaced from a sand-cast aluminum box in grey hammerite paint. MKI.V was simpler in design. However new techniques made it more stable. Again, the label Sola Sound is not appeared on the box. Also Vox was using the same circuit in their production in Italy. Only a small amount of Tone benders were produced.


Tone Bender MKI.V


Technology of the Tone Bender MKI.V


            MKI.V was the first Tone Bender using strip board and one point grounding eliminating to minimum noise and unpleasant phenomenon. Also the negative amplifier topology was a major step in design. Using only two transistors, Mullard OC75, influenced from the legendary fuzz Fuzz Face, also the circuit is quite similar. Again, MKI.V was using shielded cables and true bypass switch. MKI.V was not producing heavy saturated effect like MK.I making it more easily operated.

Tone Bender MKI.V circuit


Famous Users of the Tone Bender MKI.V


Famously used on the rubber soul sessions by The Beatles.



Sola Sound Tone Bender Professional MKII


History of the Tone Bender Professional MKII


          In the same year (1966) Sola Sound starts the production in London of the Tone Bender Professional MKII. Refreshing up the previous design of MKI.V and adding a couple of parts more created the legendary MKII. The housing is the same with the MKI.V but this time the brand name is on the box: SOLA SOUND (LONDON) LTD. Sola Sound also produced the valuable MKII for Marshal, Vox and Rotosound.


Tone Bender Professional MKII


Famous Users of the Tone Bender MKII


            Mick Ronson, Jimmy Page, Jeff Beck, Eric Clapton and many others.


Technology of the Tone Bender Professional MKII


            Tone Bender Professional MKII has a strip board, one point of grounding and all the techniques of the previous MKI.V but now with one more transistor as an additional amplifier stage. It uses tree Mullard OC78 transistors but also made with tree Mullard OC18 with were used as audio drivers in radios. The Mullard OC18 – MKII is more valuable because of the excellent response and the abilities that offered to the guitarist to control their sound.


Tone Bender Professional MKII circuit



Vox Tone Bender Professional MKII, Marshall Supa Fuzz and RotoSound Fuzz Box


Sola Sound, as mentioned before, produced MKII also for Vox, Marshall and Rotosound.


Vox Tone Bender Professional MKII


Vox Tone Bender Professional MKII is extremely rare and only differs from Sola Sound Tone Bender Professional MKII on housing, using more futuristic boxes with silver gray hammerite paint in contrast to the dark grey of Sola Sound model.


Marshall Supa Fuzz


          Marshall Supa Fuzz made from 1966 until ’70 and was the longest production of MKII. Different housing and some out looking variations were they only differences; the circuit was still the same with the unique detail that the transistors were Mullard OC78 never Mullard OC18.


Famous Users of the Marshall Supa Fuzz


Jeff Beck, Pete Townsend, Steve Hacket (Genesis), and Ron Asheton (The Stooges).


RotoSound Fuzz Box


The same case is also repeated with Rotosound Fuzz Box, Sola Sound made the circuit board and the box was from Rotosound with two variants in color, silver and gold hammerite



Vox Tone Bender Professional MKII


Marshall Supa Fuzz


RotoSound Fuzz Box Gold


RotoSound Fuzz Box silver



Vox Tone Bender


History of theVox Tone Bender


Vox Tone Bender is the most recognizable of all the Tone Benders, if you think of a Tone Bender the first thought goes to Vox. Most think that it is a British pedal because of Vox but it was producing in Italy from 1966 until the mid ‘70s. The tone of this Tone Bender isn’t like the solid, bassy Fuzz Face type of fuzz. The treble response is quite high and sound great with the dark sounding of the British valve amplifiers.




Technology of the Vox Tone Bender


The first first versions of Vox Tone Benders in 1966 had different component values from the other Tone Benders but the most significant was an OC76 transistor placed in the second amplification step in the circuit. The first Vox units were fitted with a SFT337 and an OC76 and also, had the input capacitor mounted hidden beneath the circuit board. Models from approximately 1967 still used the SFT337 but in place of the OC76 used a SFT363E and but now the input capacitor was mounted on top of the board. Again the simplicity of the Tone Bender in combination of great transistors make until now unique.



Early Vox Tone Benders OC76 & SFT337 (1966)






Late Vox Tone Benders SFT337 & SFT363E (1967)