In the 1920ies and 1930ies a lot of companies began to produce electric and electrically amplified instruments. Apart from the more successful instruments such as the vibraphone, the (electric) organ and above all the electrically amplified guitar, most of the then produced instruments (sometimes rather peculiar ones) are only of a historical interest.
The first attempts to produce an electrical bass instrument were made quite early. In 1924 Lloyd Loar (Gibson) presented an electrical double bass (Electric Upright Bass/EUB) with an electrostatic pickup, which was however not mass-produced. In 1936 Rickenbacker brought out a EUB with a magnetic pickup. As at that time there were only gut strings available for double basses, they had to be coated with metal in the area of the pickup. The firms Regal and Vega also produced EUBs at the end of the 1930ies. They had magnetic pickups with movable coils. Whereas there were already pickups for guitars available, the first pickup to amplify an acoustic double bass was not brought out before 1949: Everett Hull’s Ampeg.
Everett Hull, a bass player himself, was prompted by the guitar player Les Paul to occupy himself with the technical side of pickups and amplifiers. His pickup used a microphone attached to the inner end of the peg – thus the name amplified peg. Apart form this pickup Hull’s firm also offered a suitable amplifier because special amplifiers for double basses had not yet been brought out.
Ampeg was able to win some well-known bass players as endorsers such as Eddie Safranski (Stan Kenton Orchestra), Chubby Jackson (Woody Herman Big Band), Joe Comfort (Nat King Cole) and Oscar Pettiford. In the late1950ies a new stereo version was brought out equipped with a further microphone in the near of the bridge. 1970 however the production of this pickup came to a halt and today ampeg only produces amplifiers.Other producers used microphones as pickups as well. The firms DeArmond, Kent and Spotlight brought out contact microphones in the 1950ies. There the pickup housing was pressed against the belly by means of a clip which was fixed at the tailpiece. Premier sold a microphone that was led into the inner of the body through an f-hole.
Together with the growing popularity of steel strings in the 50ies some magnetic pickups were brought out. L&K offered a somewhat bulky pickup with a volume control which like most of the magnetic pickups was fixed at the end of the fingerboard. Schaller’s magnetic pickup is the only pickup of this period which is still available today. Magnetic pickups amplify the vibrations of the strings neither of the bridge nor the body. Therefore they are only suitable for steel strings and often make the double bass sound like an electric bass, but they are more resistant against problems of feedback. As a rule they are not very suitable for amplifying a bowed bass.
Real satisfying results could only be rarely achieved by means of these dinosaurlike pickups. One reason for this were certainly the primitive amplifiers: Ampeg’s first bassamp (1949) had a 12″ loudspeaker and just 18 watt.First attempts with piezo-pickups were made at the beginning of the 60ies. At that time William Fowler (father of the Fowler brothers who appeared together with Frank Zappa) developed and sold a piezoceramic double bass pickup. At the end of the 60ies firms such as Barcus-Berry and F.R.A.P. brought out piezo pickups together with preamps as supplements for acoustic guitars and at the beginning of the 70ies special piezo pickups for string instruments came out. They could be fixed at the bridge or on the belly by means of glue. A short time later Polytone brought out a pickup which could be jammed between the two legs of the bridge.
Meanwhile you can find a lot of piezo pickups which differ in size, design and material. A whole range of models is based on the same principle as the “classic” of Don Underwood which was also brought out in the 70ies. The piezo elements were jammed into the gaps under the two wings of the bridge. With this construction it is important that the elements neither stick too firm nor too loose. If the gap of the bridge is too wide, you should fit in the pickup with thin stripes of wood (veneer or used saxophone reeds). I it is too narrow you have to work on the bridge. It is also important that the elements lie flatly. This is also particularly important for a further popular construction, which is used in the wide spread Fishman Pickup. It uses two piezo ellements pressed at the surface of the bridge by means of clips. If the surface of the bridge is too curved, you should fix the elements at the mostly flat underside or you have to fit the upper side of the bridge accordingly.
To get a better balanced sound, some bass players use only one element of their Underwood pickup (or similar type). With only one of the elements, getting out of phase is avoided, and this can improve the sound.
Some producers also offer bridges with already integrated piezo elements. Some of these pickup elements can also be built in already existing bridges. As bridges must always be adapted individually to each double bass, you cannot go on using these systems without problems when changing the instrument.