Sampler (musical instrument)

A sampler is an electronic, usually controllable via MIDI musical instrument, record the sounds of any kind, and can play on key press in a different pitch.

Function

A sampler is capable of recorded sounds, so-called samples without delay, and in another pitch as in the recording, play back. For this purpose, real sounds are recorded digitally ( via microphone or from other sources ). In this case, the audio is sampled and stored as a short audio track, just as a sample. When playing the sampler can speed up or slow down, changing the pitch of the sound playback. There are also methods by which the pitch of the sample can be changed without its timetable is accelerated or slowed down (see time-stretching ).

Storing the analog signals is done by scanning the amplitude at regular intervals and digitization by an analog -to-digital converter. The frequency of these individual measurements is called the sampling rate. The fineness of scanning resolution is called, it is dependent on the number of bits with which a value is quantized and stored. Common in modern samplers are sample rates from 44.1 kHz to 192 kHz and 16 to 32 bit quantization resolution. Partial tremendously popular among musicians but also technically obsolete sampler with 8 or 12 bit resolution because of a " dirty " and " warmer" sound perceived a certain popularity.

The final sample has to be stored, which is now usually done on a hard drive. Early samplers used to use floppy disks. For playback, but the sound (RAM) must be present in memory. In early models, the maximum length of samples used is severely limited because the memory was very expensive at that time. To influence the sounds during playback ( for example, change in pitch ), a sampler also requires a powerful processor that can handle the necessary calculations.

Nowadays normal personal computers are so powerful that they are able to with suitable software to take on tasks of a sampler. Through appropriate software sampler of the main processor of the computer doing the tasks that are performed in hardware samplers most of digital signal processors (DSP). There are also combinations of software and hardware, expand with DSP cards or special powerful sound card to the PC.

Since a sample can not be arbitrarily long because of the limited space, the clay material while playing mostly after a certain time ( after the transient, which is particularly important for the sound characteristics ) in a loop (loop) is repeated. Since the overall sound of natural instruments ( such as piano ) but consists of more than the sum of individual tones, sampling is often supplemented by other sound production methods (eg physical modeling for simulation of cabinet resonance, etc.). Moreover, almost all the equipment over a wide range of filters, built-in effects and other sound-shaping methods, making them full-fledged feature synthesizers.

The capturing and editing samples is a costly and time-consuming work, which is why many musicians buy ready-made sample libraries on CD or DVD. There are also hardware sampler, the only play, but can not record, they are also referred to as ROMpler (from ROM, read- only memory). Nowadays include instrumental samples to reproduce all the subtleties of a natural instrument, easily several gigabytes.

Precursor

Precursor of the sampler are the following instruments, which already use techniques that the tone generator defined later:

• In the Technical Museum in Vienna " Super Piano " from the year 1928, with photo-electric sound production by means of rotating patterned perforated metal discs; In 1929 they were replaced by film wafers on which could be exposed onto optical sound technology with speech and music. It has a punch card system for creating sequences.

• Developed by Edwin Welte in the 1930s Lichttonorgel also used slices of photographic material as an audio memory.

• The basic idea to play pre-recorded nature sounds at your fingertips, is found at the Mellotron, a keyboard instrument that can play a single, about eight seconds long tape with a recorded sound from the manufacturer per key; the sounds can not be looped.

• The idea to change the pitch when playing musical sense, is found in an unnamed tape recorder in the studio of Pierre Schaeffer and Pierre Henry, which was modified so that it can play a tape in twelve different speeds, the twelve semitones the western ( diatonic ) sound system correspond.

Technically possible, the sampler was in the moment when the processor performance was sufficient to reproduce a stored sample in real time in a different pitch. The first commercially available sampler was 1979, the Fairlight CMI, which was to get at that time for the equivalent of today about 1 million U.S. $; This device differs from later compilations, inter alia, by the fact that it is the same audio sample with modified sampling takes place completely altering the pitch. Later, however Sampler maintain a constant sampling rate for playback and change depending on the desired pitch, the step size with which they select the next to be output each sample from memory contents. The Ensoniq Mirage 1985 was the first mass sampler with multi-sampling options for less than 6000 DM Akai S612 was the first reasonably affordable sampler in 19 - inch rack-mount version and was also the basis of which "people Sampler" called. He was the first sampler manufactured in Japan at all.

Software sampler

A software sampler is a computer program that emulates a sampler, so it can play back any digitally recorded sounds. It may be regarded as the successor to the classic hardware models.

This can be realized changing the pitch of a stored digital samples by appropriate sampling rate conversion ( resampling ) to the fixed sampling rate of the sound hardware output channel. In the resampling, however, particularly in increasing the pitch of the sampling theorem are violated and disturbing aliasing occur. There are many algorithmic approaches with varying computational effort to mitigate these effects; the quality that is achieved here by samplers, is one of the most important quality characteristics.

The most commonly used today softsamplers are modular and partly combined with software synthesizers. Major programs include EXS24 (only Apple Logic ), Gigastudio, Halion, Linux Sampler or contact. This software samplers are built as plug-ins for sequencer programs such as Cubase, Sonar or Logic. An independent, host- independent sampler is in MusikLaborSynth.

The samples are not loaded entirely into RAM, but only the first moments. If required, then the rest of the sample is loaded for playback from the hard drive. The shortened preparatory loading times. The Gigasampler / Gigastudio from Tascam is the first device that was equipped with this technology.

History of Software Sampler

In the early days of software sampler was the difficulty that the high - and downsampling of audio files required a lot of computing time and memory. Until the mid- 1990s, only monophonic ( unanimous ) software samplers were therefore able to run on standard PCs that certain tricks helped themselves to shorten the computation time. Thus, software sampler since about 1997 on PC real-time capable and have in virtually all areas of displaced hardware-based samplers. Benefits through lower costs, larger display ( computer monitor), more RAM, faster processing, integration with other software have led to it.

Also developed in the 1980s and 90s on home computers tracker sequencer can be expected to software samplers (or an extension thereof), as the real-time resampling is necessary capability of the tracker concept. Tracker were in the early 1980s on the Amiga 4 track resampling perform in real time (with hardware support from the Paula chip) and in the early 1990s as a pure software solution on the PC. For this purpose, highly optimized, hardware-related assembler code was written as an enabler as a pure software solution, an early example is the InertiaPlayer of 1993. A current tracker with very good sampler properties, for example, the Renoise tracker.