DE1195583B - Auxiliary generator for electronic musical instruments - Google Patents

Description

Auxiliary generator for electronic musical instruments The invention relates to an auxiliary generator to generate an auxiliary frequency necessary for generating the tremolo, whose frequency-determining normal is a one-sided oscillating in the tremolo frequency clamped mechanical transducer, e.g. B. is a leaf spring for during the Musical instruments worn by the player, preferably with electrical pick-up, but also electronic sound generation and playback via loudspeakers. It deals mainly electric guitars, accordions, and harmonicas that are either with so-called pickups or with microphones for direct or indirect conversion (via the airborne sound) of the body vibrations into corresponding electrical alternating voltages are equipped.

The known arrangements for achieving the tremolo effect (periodic Volume fluctuations) generate the desired tremolo frequency by means of electrical Oscillating circuits such as RC, LC and relaxation generators. They work using of electron tubes or transistors, and are either in a power amplifier or the musical instrument itself, e.g. B. an electric guitar, permanently installed. To the Achieving an effective tremolo effect should be achieved by the oscillating circuit The alternating voltage output and fed to the tremolo modulator is as free from harmonics as possible, d. i.e., sinusoidal.

Special requirements are placed on the modulator itself in order to the disturbing radiation of the tremolo frequency through the loudspeaker in the non-activated To avoid condition. This is by applying that in carrier frequency technology Conventional modulation devices, such as push-pull or ring modulators, can be easily reached.

For economic reasons it has so far been widely used for the musical instrument group mentioned was omitted. A transistor or tube generator represents a not inconsiderable technical effort for a musical instrument and has an adverse effect on its value for money. A further disadvantage is that in Instrument a battery for power supply must be arranged so that besides Operating costs still inconsistent operating conditions due to battery consumption appear. Furthermore, there is a tremolo modulation device with a fully electronic Generator with its own, such circuits, susceptibility to failure.

The tremolo modulation device according to the invention eliminates the described Disadvantages due to the fact that it is completely maintenance-free and there are no operating costs as a result of the absence any power source and operational reliability with the lowest possible technical effort.

According to the invention this is achieved in that a mechanical oscillator is attached to or in the musical instrument operated by a player and through the vibrations when it is actuated gets into resonance, with the oscillator and / or the parts attached to it are coupled to a transducer in such a way that that this converts the vibrations of the tongue into an alternating voltage, which on a suitable for modulating the audio frequency of the electronic musical instrument is used. The mechanical, tuned to the tremolo frequency Oscillator, preferably consists of a one-sided firmly clamped, on the free End of weight-loaded leaf spring.

The generated alternating voltage controls a known modulation device, z. B. a push-pull modulator, which is to be modulated and from the acceptance devices The audio frequency voltage supplied by the instrument is also supplied. Advantageous is that the requirement for a sinusoidal output voltage from an electromechanical Tremology generator is ideally fulfilled.

The most effective tremolo frequencies are in the range between about 3 to 10 Hz. The decay time of a mechanical oscillator at such low Frequencies and corresponding easily realizable quality is after one-off Impact (damped oscillation) is very large and amounts to about 30 seconds and more.

As a result of the persistence towards the musical instrument, with to which it is firmly connected, every shock of it suffices, e.g. B. as a result A fuss at the start of the game to trigger a dampened oscillation. There one from the musician Musical instrument worn during the game, e.g. B. an electric guitar, is moved involuntarily and firmly inevitably continuously, becomes the mechanical The oscillator is continuously excited to new damped oscillations long before these each have decayed to zero amplitude. If necessary, a conscious one is sufficient insignificant movement of the instrument to trigger the vibrations again. Around to achieve an optimal efficiency of such a tremolo modulation device, it is preferably built into a musical instrument in such a way that the involuntary Main direction of movement of the instrument, e.g. B. horizontal in an accordion, itself with the direction of movement of the mechanical oscillator, e.g. B. the cantilevered and weight-loaded leaf spring, covers.

Any fluctuations in amplitude of the mechanical oscillator that still occur can, if they are perceived as annoying, by a downstream limiter, z. B. in the form of 2 anti-parallel connected diodes, are compensated.

With the F i g. 1 and 2 is intended to be the subject of the invention in two exemplary embodiments are explained in more detail.

F i g. 1 shows a particularly simple and rigidly coordinated design. 1 with a leaf spring is referred to, which is loaded with a weight 2 at the free end. It is firmly clamped between the piezoelectric leaflets 5 and 6 and the parts 3 and 4 serving as a counterweight, the insulation aspects not shown in the drawing of course having to be taken into account in the structural design. When the leaf spring vibrates mechanically, the leaflets 5 and 6 are subjected to total pressure fluctuations in opposite directions and the electrical alternating voltage produced on them by the piezo effect is correspondingly removed and fed to a known modulator.

F i g. 2 shows an embodiment in which the tremolo frequency can be continuously regulated. The permanent magnet as used for the weight load of the leaf spring 7, by changing the distance between the permanent magnet 13 and the permanent magnet 8 may be a result of the then different mutual magnetic influence the natural frequency of the plate spring 7 and the permanent magnet 8 formed mechanical oscillator light within the desired limits changed will. For conversion according to the electrodynamic principle, it is sufficient to arrange the coils 11 and 12 so that the permanent magnet 8 , which is present in any case, can freely dip into them when the leaf spring 7 vibrates. The alternating voltage is taken from them and also fed to a known modulator. The leaf spring 7 is firmly clamped between the parts 9 and 10; they serve as a counterweight, which is attached to the musical instrument, mechanically rigid to it. Of course, the results in FIG. 1 and F i g. 2 also a large number of variants. It can e.g. B. in electrodynamic conversion, the coil oscillate and the magnet be rigidly arranged, the leaf spring with permanent magnets attached to it can be completely enclosed by an elongated coil and act as a coil core, the permanent magnet for frequency control can be on the oscillator, as already from F i g. 2 can be seen, have both attractive and repulsive effects or can be replaced by a soft magnetic material. B. a weight-loaded and unilaterally clamped coil spring can be used as an oscillator with a corresponding structural design of the transducer.

Claims (3)

Claims: 1. Auxiliary generator for generating an auxiliary frequency necessary for generating tremolo, the frequency-determining standard of which is a mechanical oscillator, clamped on one side, vibrating in the tremolo frequency, e.g. B. is a leaf spring, characterized in that this transducer is mounted on / in the musical instrument operated by a player and resonates through the vibrations when it is actuated, the transducer and / or the parts attached to it being coupled to a transducer in this way are e.g. B. the one-sided firmly clamped end of a leaf spring (1, 7) with a piezoelectric pickup that converts the vibrations of the tongue into an alternating voltage, which is used in a suitable way to modulate the audio frequency of the electronic musical instrument. 2. Auxiliary generator according to claim 1, characterized in that the weight load of the mechanical oscillator, for. B. a leaf spring (1, 7) a ferromagnetic material (2, 8), preferably a permanent magnet, is used to change the frequency of the mechanical oscillator also preferably a permanent magnet (13) in its magnetic action in a suitable manner, for. B. by changing the distance, magnetic shielding or shunt, can be regulated. 3. auxiliary generator according to claim 1 and 2, characterized in that to keep the output voltage of the electromechanical tremolo generators from a certain minimum value between its output and the tremolo modulator a known limiter, z. B. 2 anti-parallel connected Diodes, is connected in a suitable manner. Considered publications: German patent specification No. 562 955.