As your collection of vintage keyboards and MIDI modules grows, you’ll discover a new challenge… that you are woefully underprepared for the number of inputs you now require.

Most keyboards will have at least stereo outputs, or two channels. Many have multiple outputs that you might wish to take advantage of, sometimes four, six, eight or even more per keyboard/module.

Most audio interfaces are limited to just a few inputs. For example, the Digidesign 003 can handle just eight inputs. You can add an expander that gives you an additional eight channels for a total of 16. But even with 16 inputs, that would only be eight keyboards or modules, not to mention microphones, guitars or anything else that also needs to be plugged in.

One solution to this problem is to use a line level sub mixer. This allows you to mix down several inputs to just one or two. For example, an eight-channel sub mixer could mix down eight mono channels or four stereo channels to just one or two master outputs.

However, with just a few keyboards and modules the input requirements climb very quickly. Even eight mono or eight stereo may not be enough. True, you may not need all those keyboards in one song, but you certainly wouldn’t want to have to constantly plug and unplug different keyboards to discover which one you want to use.

That brings me to today’s recommendation… the Mackie LM3204 32-channel Pro Tour line mixer.

The Mackie LM 3204 32 Channel Pro Tour Line Mixer

This mixer wasn’t as widely publicized or as well known as the standard Mackie mixers, like the 1604. Although the LM3204 shared a lot of the same features it has some very specific benefits that are of interest to us as studio owners with lots of outboard equipment.

The main benefit? Well, this speaks for itself… 16 stereo channels! Yes, with this unit you can easily sub mix 32 channels of audio. It’s powerful and convenient. With this mixer I can have all of my outboard equipment always hooked up and ready to go. And all the while I’m sub mixing to stereo, so it only takes up two inputs on the audio interface to my computer.

I recently saw one of these units sell on eBay for just a little over $300. At that price it’s a real steal. You don’t see these come up very often. But if this would solve your input problems like it’s solved mine, grab it when you see it.

(By the way, these have the capability of being chained together. So if you can find two of them, that would be 32 stereo channels you would have!)