Indirect recording is what I would call the "old school" method of actually plugging into a real guitar amplifier, and using a microphone to record the sound. Minimally this method requires an amplifier, microphone, mic-preamp and a converter. However, a whole heap of other units can be added, for example eq's, mixers, compressors etc. Before we get too technical, let's first talk about the signal path. The signal path is the path that the audio takes from the microphone to get into the computer, and what happens along the way.
For example - a simple signal path beginning at your microphone and ending at your computer workstation may include the following units along the way. Below is a very basic signal chain showing how the signal travels from your guitar to your computer via various units. Guitar > Amp > Mic > Mic Pre-Amp > EQ > Compressor > Converter > Computer This illustration shows that once your guitar is amped, the sound will be picked up by a microphone, then sent to the mic pre-amp, which will boost the signal, and make it loud enough to actually use.
From there the sound source could be send to some sort of eq unit, and a compressor to alter the levels. Finally the signal is sent to the convertor which will allow the music to reach your computer. Now, if I've lost you already, fear not! Let's take a quick look at what these different units do and how they work.
Mic-Preamps - The signal that a microphone picks up is actually very low, and needs to be boosted for it to be used with your recording device. This is exactly what a mic-preamp does. It boosts the signal to a level that is useable for recording. You may already have a mic preamp on your computer; however this is only designed for speech and is unfortunately unsuitable for any serious recording Compressors - A compressor is a device that reduces (compresses) the dynamic range in a sound sources softest point to its loudest point to smooth the output, and can bring your audio material up to spec with professional recordings. An instrument that goes from very quiet and very loud over the course of a song can be difficult to record and mix. Either the quiet parts get lost or the loud sections overload the recording.
Converters - In very basic terms the converter is the equipment that takes your analog audio from your compressor, eq unit, mic-preamp etc, and creates a digital representation, which is sent to, and is now useable with your computer. Keep in mind that this is one of the most important units in your signal chain and it's well worth spending a little more money to get a high quality converter.
Ian Marples has been playing guitar for over 10 years, and now runs the website http://www.uncleslinky.co.uk to help other guitarists learn how to succesfully record music at home. For similar information to this article subscribe to his FREE Newsletter by sending a blank email to firstname.lastname@example.org