These are really only designed for Skype and similar voice applications. The recording quality is generally very poor.
This is one of the cheapest practical options for voice recording. They are also convenient and if you get a reasonably good one the voice recording should be pretty clear but will lack the polish of a "studio" recording. The microphone capsule should normally be positioned close to the corner of the mouth so that it picks up the voice clearly but does not get blown on from either the wearers mouth or nose.
The next cheapest option is a standalone USB microphone (such as the Behringer C-1 Studio Condenser Microphone )
You should generally use these quite close with a "pop shield" between the person speaking/singing and the microphone.
These can provide very good sound quality, though there may still be a noticeable amount of hiss if you are talking quietly.
Other disadvantages of USB microphones are:
- You will need to be fairly close to the computer (and its fan noise) due to the length of the USB lead.
- Unless you buy an expensive USB microphone it is unlikely to provide any means of direct monitoring which means that (on Windows) you will not be able to hear the sound from the microphone in your headphones.
- You cannot expand the system to use more than one microphone. Audacity can only access one recording device at a time, so you cannot use 2 USB microphones at the same time.
- Inexpensive USB microphones rarely have a gain control for the built-in pre-amp. If you are recording something that is quiet, it will record at a low level and you will need to amplify it in Audacity which will raise the background hiss. If you are recording something that is very loud there is a danger of overloading the microphone pre-amp and causing distortion.
This option is more expensive that the previous options as it involves buying the microphone and the USB pre-amp, but has a number of benefits:
- The type of microphone can be selected to suit the purpose and may be changed or upgraded without needing to replace the pre-amp.
- There is usually an input gain control that allows the microphone to be used with quiet sounds or loud sounds.
- There is often a headphone socket included which allows direct monitoring
- Some USB microphone pre-amps have two microphone sockets, allowing a second microphone to be used at the same time.
- Many USB microphone pre-amps also have an analogue output which allows it to be used with other recording/playback gear.
- The microphone can be used with a long cable if required.
With a suitable choice of microphone and pre-amp, this option is capable of very good recording quality.
Microphone + Pre-amp + High quality sound card
With the addition of a third piece of equipment, the price is likely to be higher, but this option may allow still greater flexibility
Microphone + Mixing Desk + Sound Card
Probably the most flexible of all set ups as as many microphones as there are microphone sockets may be added to create a stereo mix for recording.
Because the microphone pre-amps are built into the mixing desk, the signal into the sound card will be at a reasonably high level which is much easier (and cheaper) to convert to digital than low level microphone signals, so relatively cheap sound cards (such as the Behringer UCA 202) can achieve surprisingly good sound quality.
You should not plug a mixing desk directly into the microphone input of a laptop PC as it is likely to sound terrible and may even damage the laptop.
There are now a number of portable recorders available that are capable of very good recording quality in a small self-contained unit (for example the Zoom H2 and H4).
These are generally more expensive that USB microphones, but have the advantage that they are truly portable. The available features, quality, ease of use and price varies widely depending on the make/model of the device.
These should not be confused with "dictation" devices. Although some dictation devices are capable of reasonably clear voice recording, they are often limited to recording in low to medium quality compressed audio formats that can be difficult to convert to standard audio files. Also, the frequency response of the microphone is likely to be shaped to provide clear words, but not necessarily high quality sound.