Week 1 asignment

Hello Courserians,

I'm Mircea Oculeanu from Bucharest, Romania. I'm doing the week 1 asignment, recording an electric guitar or bass without an amplifier example for Coursera's Introduction to Music Production. We'll look into ways to do this when we are supposed to do it without an amplifier.

First of all, let's recall what a microphone does in a similar situation. As an input transducer, the microphone translates the movements of the air into an electric signal. Though the principles are different, the pickup of an electric guitar does quite the same with the oscilations of the guitar strings, namely it produces an electric signal.

image from HowStuffWorks.com

We'll use microphones in all sorts of situatians but the same aplies to recording guitars. Why should we be interested in recording the guitar - be it electric or bass guitar - directly into a line input? Well,  not long ago, the primary means of recording the instrument was to plug it into an amplifier and mike the cabinet; everything else was seen as a poor substitute for the sound of a real amplifier. And there were some reasons for this :) too, back at the time. If you're still not convinced by the sound aquired this way, you can get your guitar recording through a real amp later in the process in order to regain some of the dynamics you feel you're losing by recording directly. And, speaking about home studios it seems obvious why we're interested in recording a guitar direct in our D.A.W. - let me mention just the neighbours.....
Let's now remember that the pickup of an electric guitar is also a transducer, only it's functioning in a different way, that is it converts the oscilations of the guitar strings into voltage variantions. But, based on this principle, the signal is too weak to get it directly into your D.A.W. and, more important, the impedance is too high for the majority of the inputs available into any home studio.
In this situation we'll probably use an audio interface:

I chose this one simply because it's the one I've got and use. As you can see there are 2 inputs on this interface, one with phantom power - witch we don't need right now - and another one for guitar. It also has a ''special'' button tha allows you to monitor directly what you're playing, in real time. Did anyone say ''real time''? Exactly, we are hear facing one big problem of direct recording! The latency. Witch can be simply anoying or distracting and can get you out of the groove. The latency is simply the time necessary for the signal to complete the complete path of our workflow, namely the time necessary for the electric signal of the guitar to get through tha audio interface - that amplifies it to the line level and also converts it from analog to digital - futher on into the computer - and into the D.A.W. - and back till it reaches the speakers or the headphones. With all the eforts made with fast processors and so on the latency still exists, and there are couple of things you can do to diminish it but that's the subject for another presentation: :) so let's stay focused. In case your audio interface does not have the direct monitoring function we can use :

Ta daaaa!

That's the idea that the engineers came up with: the D.I. box. 

What this thingie does is very important because, first of all, makes the transition from the 1/4 TS cable - that can be very short in order to keep the level of noise down - to the balanced XLR cable that gets to the audio interface or to the mixing board. The second and of the same importance: it matches the impedance with the line input of your mixer. So we can now take the XLR out and plug it to our audio interface or directly to the mixing board. That means we can use a longer cable - the XLR cable will not increase noise and the signal loss will be minimum. Some of these D.I. boxes have a through output - parallel output - so you can monitor your playing in real time. As Loudon beautifully puts it in his video this parallel output lets you even plug into a real amp in order to hear the sound, but that's just the case when your neighbours are friendly :)...

And don't forget or I'd rather say never forget going all the way down with the gain knob when you plug or unplug the instrument or any of the cables! it really can heart your ears :)...

I hope u Courserians enjoyed my little example and I 'm waiting forward to hear from you.

Thank you