Vibrato and tremolo are very similar effects. As their name implies they give a vibrating effect to sound. The difference between them is that they achieve this in different ways.
Vibrato uses pitch modulation to alter the sound, while tremolo makes use of volume modulation.
The difference may actually be unnoticeable for an untrained ear, but musicians can use these effects in many ways to add a special touch to the sound.
Pitch modulation is achieved by smoothly varying the pitch between slightly flat and sharp. The effect of pitch modulation is very similar to the string bending technique used in guitar playing.
Vibrato common controls are rate, depth and delay. The rate and the depth of the effect determine how fast and how far the pitch is changed. The delay determines how fast the effect reaches the set depth.
Volume modulation used in the tremolo effect rapidly turns the volume control up and down. There are several different kinds of tremolo effects depending on the waveform they use to modulate the volume level.
The original tremolo processors use sine waves to achieve a smooth modulation of the sound.
There are also tremolo units that use saw waves, square waves and other combinations which give a very interesting and original sound.
The common controls for tremolo are speed and depth. The speed controls how fast the volume varies while the depth controls the amount of volume modulation.
There are also several other ways of manipulating the sound of your violin.
The volume pedal
The volume pedal is a very simple gadget that allows you to control the volume of your violin using a pedal.
Although it might not seem very interesting at first, the volume pedal is a very useful item as you can really produce some great sounds using it.
There are several things you should watch out for if you’re thinking of buying such a gadget. First of all, some of these pedals allow you to set a minimum level.
Once this is set, you can never turn the volume beneath the set level even with your heel down. Another important aspect to watch for is whether the pedal is fully controllable.
In other words, you do not want the pedal to fall on its own maximum level when you take your foot off it.
Panning is a combination of 2 tremolo effects: one controls the left channel while the other controls the right one.
The difference between panning and the simple tremolo effect is that the two effects in panning are linked so that when the volume is high in one channel the other one is low.
The volume modulation will keep the balance between the two channels creating a feeling of moving sound. The common controls for this device are speed and depth (the same as in tremolo).
Harmonisers add notes to the ones you are already playing. There are several types of harmonisers.
The first ones were the so-called octave dividers. They add a distorted signal one or more octaves below the notes you play. The disadvantage with these first harmonisers is the fact that they can only work on a single note at a time.
The second generation of harmonisers, the ones that are being used today, use several techniques to store and then retrieve the sounds you played in order to preserve the character of the playing.
They also offer the monophonic harmonies (like the ones above) but the quality has improved. A very interesting aspect is that they offer full control over the harmonies to be played.
For example, you have the option of chord based harmonies which allow you to set an interval determined by a key you set and the note played.
Besides these common effects which you can find in any music store, there are also processors which manipulate the sound and apply some combinations of common effects.
Such a device is the G-Major processor (build to be used with guitars) which also offers such effects like Resonance Filter, PingPong, Dynamic Delay, Dual, Pitch Detune, Whammy, Pitch Shifter and others. For more information on this processor visit TC electronic.
If you want to find out more about available effects products go to Active Musician. Again, this site was initially built for guitar players, but the processors and units are the same.