Intel Peavey ReValver MK III - Manual (Page 5)

Connecting the Guitar to the sound card
Here are three ways to connect your Guitar to the computer:
1) The simplest option is to hook it up to the sound card Line-In jack using a suitable connector,
usu ally a 1/4” to 1/8” adapter. The advantage is that you don’t have to buy any additional gear
(except maybe the cable adapter) but the sound is not ideal, probably not even good. The reason
for the dull and boring sound is due to an impedance mismatch.
The sound card input is designed to accept input from electrical devices which have adequate
driving signal; a Guitar does not have enough signal. The input impedance of a sound card is in the
order of a few thousand ohms (kOhm), while ideally, you want it to be around a mil lion ohms (1
meg ohm).
2) Another option is to use a Direct (D.I.) box or Preamp. DI stands for Direct Input or Direct
Interface. It is an electrically powered box that can be used to match the input impedance of the
sound card and the output impedance of the Guitar. The simplest DI box could cost around $20,
but there are boxes that could easily cost $200 if you want all the “extras,” too. A DI box has a Hi-Z
input, (“Z” is the unit of Impedance; High Impedance input, in other words). To record, you just
plug the DI box directly into the computer Line-In jack.
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