Dewtron Mr Bassman
My first bass pedals were made by a small company, Dewtron, and called "Mr Bassman".
It was 1975 when I bought them, second hand. I was talking to the salesman behind the counter in a music shop in Kings Lynn. I mentioned Jesse Fuller, the Fotdella and my one man band ambitions. I had to explain what a Fotdella was. He said "Hang on a moment", and after ferreting around in a cupboard behind the counter, emerged with what I was to learn was a set of Mr Bassman pedals.
The photograph on the right is not my Mr Bassman but from a set of photos of the one used by Mike Rutherford, of Genesis, taken on 1 May 1975 at the Hippodrome, Birmingham.
The pedals were mounted on a slightly wedge-shaped steel box and finished in a blue metalic hammered paint finish. Mounted on the top surface was a crude set of black and white plastic "keys" arranged like those on a piano. Above the keys were a set of rotary controls for Volume, Tuning and Sustain and two rectangular foot switches. One of these toggled the sustain feature on and off. The other toggled the pitch by an octave. On my pedals the two switch covers were black, while those in the photograph appear to be white.
While the steel case was robust, all the fittings mounted on it appeared to be of very cheap brittle plastic. The keys were held in place with two screws pointing upwards through the casing and going into the bottom of the key mouldings. The screws were deliberately left loose to allow the key to move. A spring, or maybe a block of sponge rubber, I forget, held them up in their normal, at rest, position. They were nothing more than piano-like decoration, as the tones produced by the instrument were sounded by the underside of the keys pressing on very simple non-latching push button switches mounted on the top of the casing. They were the kind of switch you might have found on almost any table or wall lamp you would have encountered at the time.
The main foot switches were equally crude. They were operated by similar, but latching versions, of the push-button switches used to sound the notes and were hidden under a hollow block of coarse grained sponge rubber glued to the casing and which surrounded the switch. Glued on the top of the sponge was a simple rectangular plastic cap, the sides of which only reached part of the way down to the steel casing, so that when pressed with the foot, the underside of the plastic cap would actuate the switch. The only external connection was a 6.3mm jack socket, which took a lead straight to an amplifier.
The underside of the case had four simple rubber feet in the corners with screws within them that held the base plate in place. Removing the screws revealed the workings on the instrument and was how you gained access to the battery. This was of the PP6 type. (The PP6 uses the same connector as the, still current, 9v PP3 battery, but is about double the height and square in cross-section and, crucially, is only rated at 6v.) These became unobtainable soon after I bought the instrument. I resorted to using part used PP3 batteries and it was this that, I believe, caused the eventual downfall of the instrument.
As I recall, the bulk of the visible works inside the device amounted to a pair of stiff straight wires to which each note switch was connected, via a small circular control, which could be adjusted with a screwdriver. These controls adjusted the pitch of the notes enabling fine control of the tuning of each note. There was a further control which seemed to act as an overall tuner, in similar fashion to the external control on the top of the instrument.
I'm not sure that I ever tested it fully, but the external pitch control probably had around a full octave of adjustment in it. There was a white dot painted on the control which was normally set at 12 o'clock for concert pitch. I used it very much like a capo on a guitar, so I only had to learn a limited number of note sequences to play in a number of keys. I recall that to produce the equivalent of a capo on the second fret I would turn the control to around 1 o'clock and for the fourth fret around 2 o'clock. The total movement of the knob would have been from about 8 to 4 o'clock.
Clearly, none of the circular components I've described generated the notes. Labels on the machine indicated that Patents were held (or pending, I forget which) on the device and the method of protection employed by Dewtron of their intellectual property was to encase all the important secret stuff in a block of resin! For the cables from the battery and those from the various control circuits all disappeared into a slightly tapered block of mainly grey resin, with a few pink and blue flecks, which was about 2.5" x 1.25" x1.5" in size.
As for the sound of the machine. It's a straight forward tone with instant attack and decay as you press and release the key. With sustain turned off and a quick stab on the pedals you might as well be listening to a drum. With sustain turned on the sounds decays like the plucked string of a bass guitar, depending a little on how much you turned up the sustain. There are no other voices or options.
After a few years I forgot about the need to use flat batteries, fitted a new PP3, and soon found that the device was no longer hitting notes accurately. No adjustment to the internal tuners had reliable effect. Eventually, I decided that it was the high voltage that must have caused the problem. By then, I was no longer playing regularly and, because all the works were hidden in the block of resin, decided that it would be unrepairable and threw it away.