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This is a handy way of setting up your small mixer for recording.  In big fancy studios, you often have the ability to make a copy of your input and send it to your recording device.  This allows you to setup headphone mixes and rough mixes of your inputs on your mixer, while still being able to record individual tracks unmixed.  

The rough idea is this :

Fig. 1: Direct Out Signal Flow

When you setup your Direct Outs like this, you can set a good level for your microphones and record that track.  But you can also setup a headphone mix, apply some Eq, even create a rough mix to your speakers, without affecting the recording.  

It’s a really clean way to work, and gives you lots of flexibility.

The only problem is, most small mixers don’t give you Direct Outputs.  They pretty much only have a mic input, a line input, and a stereo insert jack.  Thankfully, these manufacturers had the foresight to design the insert jack to be able to double as a direct out.  

How?

The basic setup is to use a 1/4″ cable (guitar jack) and plug it half way into your insert jack. How do you know when you’re half way down?  

If you take your cable and plug it in all the way SLOWLY, then you’ll feel two distinct points of resistance.  The trick is to push past the first point, but not past the second.  This allows you to bypass the “break” in the signal flow that would happen if you plugged it all the way in.  

Fig. 2: Top: Normal Insert Contact Points. Bottom: Using Insert as Direct Out.

You can see what I mean a little more precisely in Fig. 1.  The red lines indicate the physical metal contacts that the plug encounters when you plug a stereo cable into an insert jack.  (If this is a bit confusing you should consult our small mixer signal flow article here.)

Fig. 3: Three Divisions of a Stereo (or Balanced) 1/4" Cable.

The Stereo Guitar cable is also called a TRS, which stands for Tip, Ring, Sleeve.  These terms indicate the three parts of the cable that carry their own signal.  In Fig. 3, you can see that they are divided by blue lines.  

When you plug in your cable normally to use the insert jack, the Tip makes contact with the “out” and the Sleeve makes contact with the “in.”  That allows you to send the signal out to a processor and bring it back to your mixer right where it left, all in one cable.

In order to use it as a Direct out, you simple let both the “in” and the “out” make contact with the tip. As you only need a “tip” in this setup, a mono cable (regular guitar jack) will work fine too. Once you’ve plugged in half-way, your signals will flow as shown in Fig. 4.  

Fig. 4: How Signals Flow using Insert as Direct Out.

The green arrows show how audio flows out from the mixer into the cable Tip and back in to the mixer.  The purple arrow represents the copy of the signal you just made.  

The copied signal (purple) is your direct output of the mic Pre-amp, which you can send directly to your recording device. 

As small a trick as this might seem it allows you to make a really powerful recording setup on a small budget. Some of the benefits are:

1) You can setup headphone mixes/rough mixes at your mixer, without having to go through your computer. This cuts latency down to nothing.

2) You can make Eq changes that benefit your headphone mixes, without recording them.

3) You get an extra level of gain control because you have a mic preamp, and then the line input level on your interface.

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