What's the easiest way to utilize the stereo tracks on my Zoom L-12 as microphone inputs?

Question

I have a Zoom Livetrack L-12, and I'd like to to use the two stereo channels as individual microphone channels. Obviously, I will need a microphone preamp for each of these channels in order to do so.

My first thought was to just get a cheap interface (e.g., the Behringer U-Phoria UMC202HD) and send the signal from the 1/4 in. outputs on that into the 1/4 in. inputs on the stereo channels on the Zoom. However, the 1/4 in. outputs on the interface are TRS (mono) balanced and the inputs on the Zoom are TS (mono) unbalanced. So, without a DI box (or, perhaps, pulling one of the jacks halfway out—which I'd like to avoid), this can't be done properly.

My next thought (with the same interface) would be to just take the 1/4 in. headphone output (which is obviously a stereo TRS jack) and break that out into two unbalanced mono signals, which I would then plug into the two channels of the Zoom. However, for this to work, the two XLR inputs on the interface would necessarily have to be assigned to the left and right channels of the stereo signal (respectively) of the headphone jack. I can't tell if that is the case for this interface, and ones like it (perhaps that's typical—I don't know).

Would the above approach work? And/or is there a simpler/cheaper alternative to achieve what I'd like to achieve?

Answer 1

You might want to read This PreSonus Article But you should be fine to connect a balanced TRS to TS. But are you really needing 10-12 mic inputs? you'd be better off buying a mixer with more inputs. But in any case here are some clips from the article.

These days, most equipment is designed so that balanced and unbalanced connections in a system can be mixed successfully, but different input and output circuits require different ways of making two wires out of three (or one wire out of two, if you don’t count the shield).

The proper way to connect this type of active-balanced output to an unbalanced input is to simply leave pin 3 disconnected. Signal voltage appears between pins 1 and 2, which is just what our unbalanced input wants. This is another instance where you’ll probably need to modify or custom-build a cable if the output is on an XLR connector.

If you have this type of balanced output on a TRS jack, you can usually use a TRS-TRS cable to connect it to an unbalanced input. A TS (unbalanced) jack at the input makes no connection to the plug’s ring, which will leave it floating, as we desire. However, some manufacturers thoughtfully use a TRS jack for an unbalanced input, wiring the jack’s ring contact to ground. This assures that you’ll get signal between the unbalanced input and ground when using TRS-TRS cable to make the connection from a balanced output.

Answer 2

Behringer U-Phoria UMC202HD

That's a peculiar choice, it does far more than you need (AD/DA conversion). And the 1/4" outputs are connected to the DA converter, not directly to the inputs. This means you will have lag between the inputs and the 1/4" outputs, and you'll need to connect the interface to a computer for these outputs to work.

You could use the Phones output, it looks like that has a direct connection. A simple TRS jack->2x TS jack cable is enough to connect this to the mixer.

As an alternative, an analog microphone preamplifier (link goes to a random selection) contains everything you need for your application.

But either way, the drawback of your approach is that you now have 2 inputs that share 1 gain setting, 1 EQ and 1 fader.

The Behringer offers individual gains, so that's not a big issue. But having to share 1 EQ and 1 fader means you're limited in what you can use these channels for.