Submix™ Using & Applications

The Submix combines tremendous flexibility with ease of use. The following describes how to use the Submix in both a Workhorse and older 500 series racks. For complete details, we invite you to download the manual by clicking on the icon at left.


The Submix is a high quality 4x1 mixer designed for 500 series racks. The compact 'single wide' design makes it easy to increase the channel count of your analog system while still giving you individual level control over each input. And with four conveniently located ¼" jacks on the front panel, plugging into the Submix is immediate.

Following the block diagram, you can see how the signal flows from the input to the mix buss and then, the summed output is sent to the 15 pin card edge where it is collected by the power rack to feed the rear panel XLR. With a Workhorse, the XLR also feeds ¼" TRS connectors and D-Subs.

You will also notice that with the Submix, the Omniport is designated as an input. This enables another Submix to be connected to create an 8x1 mixer without sacrificing one of the input channels. If you have an older API rack, you can still send the output from one Submix into the channel of another, but this will limit your channel count to 7x1.

Making connections

Before inserting the Submix into your power rack, turn off the power and reduce the level controls. This keeps equipment safe from turn on transients and connection sparks that could cause damage. Once the Submix is screwed in and secured in place, you are now set to power up. Using a power bar makes turning on & off equipment easy and generally reduces system noise by bringing all of the electrical grounds together and matching the electrical polarity.

Start by setting the input levels to minimum (counter-clockwise) and ensure all of your audio levels are turned down. To test signal flow, plug in a source such as a keyboard into channel-1 and connect the XLR output from your 500 series power rack to your recording system. Slowly increase the levels on the recording system and the Submix until you hear audio. If everything is working, you can now add a second device by plugging into input-2.

Although the Submix is unbalanced, you can actually connect just about any type of input. If you send in a high output balanced signal, the Submix will unbalance the signal and reduce the level by about 6dB. The Accustate input circuit will also keep things quiet!

Using two Submix Modules in Stereo

For most studio production, we tend to set things up in stereo. With 500 series racks, one simply 'doubles up' by patching two Submix modules side by side to create a stereo setup. Assign the first Submix 'left' and the second 'right' and then patch in as needed. Send the outputs to the left-right input on your workstation or pan the channels left and right on your Radial Workhorse.

Creating larger mixers

If you have a Radial Workhorse you can easily create 8x1, 12x1 or larger mixers by cascading several Submix modules together. Feed the balanced output of the first Submix into the Omniport input of the second. The Omniport function on the Submix is designated as a mix-buss input whereby multiple modules can be combined without adding noise or distortion.

Feeding one Submix into another

If you are using an older API rack, you can feed one Submix into another by simply patching the output of the first into channel-1 of the second. This will result in a 7 x 1 mixer with channel-1 acting as the group master for the first Submix. If you are equipped with a Workhorse, you can also create the same setup by simply engaging the FEED function. This is the same as using a patch cable but frees up the XLR for other tasks. You should NOT use the front ¼" input at the same time as this could cause interference.