The A-100 can be used to process any audio signal (electric guitar, microphone, midi sound module, computer sound card, CD player, tape-recorder , mp3 player  ...). But one has to pay attention to some special features of the A-100:

• The audio inputs of audio-processing A-100 modules (e.g. filters, VCAs, phaser, flanger, waveform processor, distortion, wave multiplier, ring modulator, frequency shifter, spring reverb, panning ...) require a minimal level of about 1Vpp. Otherwise the signal-to-noise ratio may become very poor. A higher level is no problem because virtually each audio input is equipped with an attenuator to reduce the signal level. If the signal source does not have the required level an external pre-amplifier is recommended. Especially for low level sources like microphones or electric guitars an external pre-amplifier is required.
• Additional controlling modules (e.g. low frequency oscillators/LFOs, envelope generators/ADSRs, random voltage generators, slew limiter, Theremin, Ribbon controller, Joy stick ...) are normally used to control the parameters of the audio processing modules (e.g. filter frequency, filter resonance, loudness, clipping level, wave multiples, phase shift, delay time ...).
• The A-100 uses 3,5 mm mono jack sockets and has asymmetrical inputs and outputs. A special cable or adaptor that converts the plug type of the sound source (e.g. 1/4" jack or RCA or XLR) to a 3,5 mm mono jack plug is required. For 1/4" jacks the A-181 can be used. We also offer 3.5 mm to 1/4" adapter cables.
• The external input module A-119 is recommended if the envelope of the signal (e.g. to control the filter frequency, loudness or any other voltage controlled parameter of the A-100 modules) or a gate signal (e.g. to trigger envelope generators) are desired. It has also included an amplifier that may be used to increase the signal level of an external signal. But it's not a "high-end" pre-amplifier and may be not sufficient for high quality applications. In this case an external high-end pre-amplifier is recommended.
• A list of all available A-100 modules can be found on the A-100 modules overview page.