For a music band, synchronous 4-track sound recording is the absolute minimal setup. Recording instruments on four discrete channels improves the sound quality and makes the master mix easy. The Zoom H2 has that (hidden) opportunity, because it can record sound from the 4 built-in microphones simultaneously. The only thing we need to do is to add 4 line input plugs and 2 switches. To change the sound level we solder some resistors and capacitors into the box. As reward for the modification you get a cheap multi-track field recorder in the palm of your hands.

The video below shows how to get it done.

Project Steps

The Zoom H2 can record 4 tracks simultaneously but only using its 4 built-in microphones. This modification makes recording of 4 signals at line level possible.

You have to install 4 input jacks on the back of the unit. The resistors shown in the diagram reduce the input signal by 40dB. The capacitor blocks the DC part from the input. Switch S1 chooses line input or microphone.

After drilling the holes on the back of the H2, install the 4 jacks and the 2 switches. RCA jacks are used here but other kinds of inputs are also possible.

Now for the soldering part. Take care with the soldering iron; there is not much room inside the box. Watch for short circuits. Insulate when necessary. Work clean; check the connections.

The middle photo shows how the switch is connected to the 4 microphones at the top.

The right photo shows the compact placement of the new components.

The left photo shows the soldering of the resistors on the input jacks. They have to be pressed into place beside the jack.

The middle photo shows the Zoom H2 connected to the 4 outputs of the sound interface (8 channels in total).

The last photo shows the H2 in recording mode. You can see the display with the volume meters. Here you can check the volume levels. You can change the gain using the gain slider. This is the finished product. Success!!!


You need some experience with soldering small connections. You need to have the courage to open the recorder and to make this hack in a crowded enclosure.