FREE MP3'sFREE Recording Handbook

Now accepting online credit card payments
for these fine JeepJazz Project CDs!

Recording Handbook
Chapter 4: The Mixing Console

 4. The Mixing Console

The mixer is just that. We use it to organize our signals going to the tape machines, to organize what we need to hear back from the tape machines, to monitor playback from our mixdown DAT, 2-track or other stereo sources, and to add effects to whatever is needed. In short, it is the heart of the multi-track studio.

a. Inputs and Outputs

Recording consoles are designed to be connected to multi-track tape machines. They provide seperate mixer inputs for our sound sources(mics and line inputs) and the tape returns (signal playback from the multi-track) and multiple outputs from the mixer to the tape machines (both as "direct outs" from individual channels and through the "bussing matrix"). In addition, the input channels with a choice of line or microphone input also offer equalization, effects sends, pan, buss send options and a fader for volume on each channel strip.

In-line consoles include the input section and tape return level and pan on the same physical channel strip. Split console designs have seperate channel strips for inputs and tape returns, usually with less EQ and effect sends on the tape returns (the "monitor section").

Semi-pro and home recording gear operates at a -10 level while professional equipment operates at a +4 level. Without getting too technical, this means you have to pay attention to the particular input and output levels of your boxes and how you interconnect them. When it's not right, it often hums or sounds a little screwed up. It still might work, but it will give you much less than optimum performance.

To be sure that the sound at the source gets "through the gear and back to your ear", you need to check the "gain stages" in the "signal path". Distortion can crop up in several places. Step one is your ear! Make sure the sound at the source is what you want.

Step two is the microphone or direct output of the guitar, synth or whatever. In the case of a microphone, the levels must be set carefully to ensure faithful reproduction of the input. Some mikes have a "pad" switch on them as do most mixers, to prevent overloading the input level.

Step three is the input channel to the board. The level here must be set so that the signal doesn't overdrive the channel electronics. Once that is right, the signal can be sent to tape through the "bussing" matrix (or "group outs" as they are sometimes called) or the direct out on the channel. Obviously with multiple signals to one track, they must go through the group outs and the level to tape is controlled by the group output level.

Generally, in the analog world, very bright sounds get printed a little lower, to help prevent crosstalk bleed to adjacent tracks. Sharp transient sounds and low frequency stuff like bass can be printed hot to take advantage of tape compression. Slamming the tape isn't against the law, but make sure that's the sound you want. This is only an analog phenomenon, overdriving digital recorders results in highly unusable audio!

Tape return levels are optimized for direct connection to the machine so if this has been done correctly, there is only one place left for distortion to be created... your monitor system. As long as you are aware of how your speakers and listening enviornment are affecting the sound and you listen within the volume limits of your amp and speakers, you should have a baseline for clean signal reproduction. Now, you can introduce distorton at any of these points in the chain to any effect you prefer.

b. Equalization

"Equalization" is the term used to describe the process of changing the balance between high and low frequencies. Equalizers allow us to selectively boost and/or cut specific frequencies or bands of frequencies. "Q" refers to the width or range around the centered frequency that we are EQing, that is also affected when we boost or cut. A narrow "Q" would be .2 of an octave, a wide "Q" would be 3 octaves.

There are many types of equalizers and they get used in many different ways by different people. In general, "Parametric Equalizers" allow for very specific effect with adjustable Q and frequency control for each frequency band. "Graphic Equalizers" feature as many as 31 individual sliders centered on fixed frequencies. Tube equalizers utilize vacuum tubes in their circuits as oppossed to transistors ("solid state") and are often preferred for their warm sound.

All mixers provide some kind of EQ, switchable on or off, in the signal path. These days semi-pro consoles usually feature a couple of overlapping bands of semi-parametric EQ on the low-mids(200-2K) and hi-mids(1.5K-7K), and one EQ each for the low(100 hz) and high(10K) bands with shelving switches and low-frequency roll-off. Professional consoles offer fully- parametric designs and more overall flexibility, as you might expect.

Since we can't all afford Neve VR consoles at home, another option for small studios is outboard equalizers. Get a couple of good ones and insert them into the signal path and print through them to tape. This will definitely take your sounds up a notch without totally blowing your college fund.

c. Effect Sends and Returns

There are several ways to get signal to your effects and to hear those effects back. The easist is the dedicated sends and returns on the mixing board. Sends can usually be switched between pre and post EQ. Returns generally have little or no EQ, so if you want to EQ effects, that's one more reason to have more channels than tape machine tracks. If you have more effects than sends, repatch the busses as sends or use the direct outs to get into your other effects.

d. Insert Points and Patchbays

It's really nice to plug everything into the board and not have to mess with it. This is where patchbays are a necessity and incredible convenience. Every in and out on the board, all tape machine inputs and returns and all inputs and returns from your effects are duplicated in the patchbay. Every channel also has an insert point as well for individually accessing the signal path. When it's all plugged in, you can change, rearrange and repatch it all from here.



JeepJazz Music
8 Graham Terrace
Montclair, NJ 07042

2013 JeepJazz Music