What is a channel strip? Why should you use one?

The channel strip dates back to the days of the analog mixing console, like this one...

You can see the channel strips on the left. Each one has a microphone input and also a line-level input. These two inputs are either/or - you can't use them both at the same time.

Each channel strip, or we can just call it a channel, on a large-scale console, has the following features (not all consoles have all features)...

• Gain control
• Equalizer
• Compressor
• Noise gate
• Auxiliary sends
• Pan
• Mute/solo
• Fader

You can use all of these controls while recording, or you can leave them in their neutral settings while you record and only set them when you mix.

If you use the EQ and compressor, for example, while you record, the settings are 'baked in' to your recording.

If you record 'flat', meaning with the controls switched out or neutral, then you have complete flexibility to set them as you please during the mix.

It's a more versatile way of working to leave EQ, compression, etc until the mix. But sometimes you know exactly how something should sound and it's best to make that decision when you record.

Standalone hardware channel strips

At some point in history, a wise person decided that it would be useful to mount a mixing console channel strip in a box of its own. So you could for instance take a Neve channel strip to any studio and have the Neve sound available. This would be on just one channel, or a pair if you had boxed up two, but you can use them multiple times as you record overdubs. You can also use them on one or two instruments or vocals while you mix. Or if you have a pair of channel strips, you can process the whole mix through them.

At some later time, audio equipment manufacturers started making their own channel strips, completely independent of the mixing console.

An example of a hardware channel strip

Here we have the Neve 8801 channel strip, which is a repackaging of the electronics from a single channel of their 88R mixing console.

If we scan this from left to right, these are the main functions...

• Microphone or instrument input (DI) - the line input is on the rear panel
• High-pass and low-pass filters
• Compressor/expander
• Equalizer
• Output level control

What's missing that you would also find on an actual mixing console channel are the auxiliary sends, pan, mute, and solo. These functions are not relevant to a standalone channel strip. They could be if you had a number of channel strips, but then surely it would be easier just to have the whole console.

As a single-channel hardware unit you can use it to process any instrument or voice as you record, but clearly only one channel at a time.

You can also use it to process one channel while you mix.

It is also possible to process individual tracks in your DAW (digital audio workstation) and bounce them back into the session. You can process as many tracks as you like, one by one. You will have to account for the small amount of latency (time delay) in the round trip out of and back into your DAW.

Plug-in channel strips

Software channel strips can mimic real hardware, or they can be complete works of invention that don't exist in the physical world. This one, from SSL, clearly has the SSL look and one can assume that it has something of the sound quality of a physical SSL console.

What we see here are the following functions...

• Low-pass and high-pass filters
• Equalizer
• Compressor
• Expander/gate
• Solo
• Mute (labeled 'cut')
• Input and output levels

But there are features here that you won't find on a hardware channel strip...

Firstly there are presets, and of course, you can store your own settings. With a hardware channel strip, you would have to write down your favourite settings, or store them as a note on your phone. That really isn't too much of a hardship, but clearly, the plug-in is going to be faster, and it's practical to create a hundred of your own presets if you like.

Secondly, you can change the order of the processing. Some hardware channel strips allow this, but a plug-in can always be more versatile. The side chain of the dynamics section is extremely flexible too.

One interesting point about the plug-in channel strip is that it is almost always used while mixing, not during recording. The reason for this is that DAWs make this easy to do. If you want to record through the channel strip then you can route your input signal to an auxiliary channel with the channel strip plug-in set up as an insert. Then route that auxiliary channel to an audio channel. Hit record and you'll capture all of the wonderful channel-strip-ness with filters, EQ, and dynamics set however you please. And that will be baked into your recording.

Why use a channel strip plug-in when you can use individual plug-ins?

Yes of course you can use a plug-in for filters, another for EQ, another for compression, another for expansion or gating. They can each be from a different software developer. You have complete freedom to use any plug-ins that you have installed in your system. That way you have maximum flexibility.

You also have maximum complexity. Sometimes it's easier just to use one plug-in that can control all of the major processes.

Also, if you use the SSL channel strip, or any plug-in that emulates an analog mixing console, you can expect to get the 'analog sound'. There is such a thing, and you'll mostly find it if you push the levels hard. Used with care and tastefulness, it can help bind, or glue, together all of the individual instruments and vocals in your mix.

Summary

A channel strip is a great way of presenting the most-used functions in audio in a single box or a single plug-in. You can also get the 'analog sound' in your recording and mix. Hardware or software, a channel strip is a useful addition to anyone's studio setup.