You may have noticed by now that the term “channel strip” can mean different things—three to be precise. There are channel strips on your mixer (both hardware and software), channel strips mounted in your rack, and plug-in versions in your DAW. These all have similarities and work on basically the same thing—guiding your input through the signal path in as small a footprint as possible.
The Mixer Channel Strip:
On my mixer (not the one pictured below, but pretty standard), there are eight different stops along the signal path.
1. The XLR and 1/4” inputs are at the top of the mixer. This is where you introduce the signal from a mic, instrument, or piece of gear. It can accommodate both mic and line level, balanced or unbalanced signals.
2. A Low Cut button controls the low-frequency roll-off. In my case, when enabled, low frequencies roll off starting at 75Hz at a rate of 18dB/octave.
3. The Trim or Gain knob adjusts the sensitivity of a mic or the gain applied to a line level input.
4. Several EQ knobs adjust various frequencies. This is one spot where the size of the mixer matters significantly. On small mixers, there are few pots, while larger mixers allow several sweepable EQs and variable high- and low-pass filters.
5. Auxiliary sends determine how much of a signal is bussed to other parts of the mixer. These are often used in monitor mixes and effects.
6. The Pan knob controls the mix between left and right signals, without moving either to the other side. Most audio into a channel strip is mono, so this is more about placing the sound in the mix. In some cases, panning is used to record 2 mono tracks from a stereo recording bus.
7. After a Mute button, we get to the level fader. The strip is set up so you get the most play (headroom) with the fader at nominal (0) when you set the gain you want. The fader is mostly for temporary, on-the-fly level changes.
8. Additional buttons. Solo mutes all other tracks; Sub sends the audio to a submix; and Main sends it to the main outputs of the mixer.
Since all channel strips have some of the same features, the others will be quicker to explain.
Rack-mounted Channel Strips:
These are mostly used to treat the most important inputs before sending them into the mixer/interface. More often than not, a specific strip is chosen for its clean or wet (usually warm) preamp, but channel strips also offer a range of effects processors in the same unit.
If you’ve treated your room well, are using a mic that’s great for your vocalist, and have EQ’d to perfection, and still can’t get a professional sound, there’s a chance your mic pre is holding you back. Some studios spend thousands of dollars per mic pres, just to add a little warmth to a sound. You could spend a few weeks researching the difference between tube and solid state pres, then another month deciding which pre to actually buy. In reality, there are clean, warm, and dirty pres in both tube and solid state varieties, and the best way to choose one is to test them yourself.
At the very least, and if it’s not too late, do some research into the interface you own or are considering. There are a lot of budget interfaces for small studios that are all priced about the same, but their preamps can be considerably different; some interfaces don’t even have pres. Of course, you won’t get a $1,000 pre in a $60 interface. Cheap pres are generally in cheap channel strips, mixers and interfaces, but you can find the best pre for your price range. The one above, for example, has a “Class A” preamp, which means it’s a power hog with pleasing distortion; it also retails for hundreds of dollars and only accommodates a single input.
If you want to know more about selecting a rack preamp, see this guide: Sweetwater Mic Preamp Buying Guide.
So, what else is on the channel strip? As the Sweetwater guys say, getting a channel strip is a cheaper way to get a really expensive sound for one input. To get that sound, you usually need effects. After the input gain stage, strips can have a compressor, EQ, de-esser, enhancers, etc . . . Do you need all that? Possibly. When you do, it’s a great way to avoid having to buy a dedicated piece of gear for each of those effects. In the case of a DAW, it helps cut down on the large number of plug-ins that crop up when mixing.
DAW Plug-in Channel Strips
There are channel strips in the DAW mixer, but they are pretty much the same thing as a hardware mixer. The main change is the plug-in section that routes the signal path through any number of additional effects, and the larger flexibility in sends/auxiliary outputs.
Plug-in channel strips are another matter entirely. They can have an input gain stage, even if that can be taken care of before the signal hits the plug-in. They can also have any number of effects, since they don’t have the limitations of hardware gear. For example, a plug-in might have a 7-band EQ, with sweeps on every band; that would take 14 knobs in real life!
I’d categorize these strips into only a few groups: simple, complex, and hardware emulation.
Simple strips, like Presonus’ Fat Channel or Avid’s Channel Strip, contain a noise gate, a compressor, and EQ. Even at this minimalist level, each of those effects still has more controls than their hardware counterpart—a standard gate has 2 pots, while Avid’s gate has 7 options.
Complex channel strip plug-ins can look intimidating and messy. Eventide’s Ultrachannel, for example, has an input gain, phase switch, gate, compressor, o-pressor, 5-band parametric EQ, pitch shifter, stereo delay, and output gain—41 pots, several sliders, and a bunch of buttons. Basically, these can be all-in-one solutions, from input to output. If you want more details and some hands-on comparisons, here’s Sound on Sound’s article on choosing channel strip plug-ins.
Hardware emulation effects can be golden! Companies like UAD and Softube work tirelessly to write algorithms that will re-create the sound of gear that only the most prestigious studios own in real life. This happens with other rack effects as well, but channel strips give you the most toys on one package. In one tutorial I watched, the engineer ran his entire mix through three separate hardware-emulated plug-ins (about $1,000 total), with all the setting off, just to add a little warmth. This is one spot where the difference between pro and home production is sometimes stark. UAD offers 4 strips, at around $250, while Softube’s 2 strips are $329 and $489, respectively.
Have some fun delving deeper into the world of preamps and channel strips. Always remember that making music is what matters, and artistry will always be more important than gear and plug-ins.