Recording Glossary I
A short list of Recording gear and terminology
by Shawn Maschino
The Home Recording Web Site
this is taken from Shawn's home recording FAQ
What is a 2/4/8/16/24... track recorder?
A 2/4/8/16/24... track recorder is what you will be using to record your music.
An example of a 2 track recorder is a cassette deck, it has 2 tracks, one on the left and one on the right. Though you can record different things on to each track, most people simply use a 2 track machine to record the left and right channels of music. Most standard 2 track decks must record both tracks at the same time.
However, a multi track recorder has the advantage of being able to record on only one track at a time, or on all tracks at the same time - much more flexibility which will be critical in recording your music.
4 track machines are normally your entry level into multitracking. They allow you to (initially - again see "bouncing" below) record 4 separate and distinctly different tracks of music - i.e. drums, bass, guitar and vocals. An example
of a 4-track would be the Yamaha MT140. Many 4 track machines have a built in mixer, aux sends, and punching ability.
4-tracks machines - like most 2-track machines - usually use standard cassette tapes as their recording medium, although unlike your standard cassette player, you can only
record on 1 side of the tape.
Some 8-track players also use cassettes but the higher quality ones use mostly 1/2" open reel-to-reel tape. 16 and 24" are almost always open reel, many with the tape width of up to 2"'s. Most digital multi-trackers, such as DA-88,s or ADATs don't use standard tape, they either use DAT cartridges (which is a form of tape), direct hard drive recording, or a very high quality form of video VHS tape.
What is a mixer?
A mixer is a component that allows you to connect all your instruments, and peripheral equipment to your tape recorder. It allows you to control the individual level of each instrument begin sent to tape, to control the tone of the instrument via equalization, or EQ, as well as the amount of "effect"
being added to each instrument from your peripheral effect processors. (more on this later)
Mixers usually have at least 4 inputs, but can be as many as
48 for the big boys. This means that you can plug in as few as 4 instruments or microphones, or as many as 48 instruments or microphones - and be able to control each one individually.
A mixer for home recording purposes should have at least stereo monitor outs, and stereo outs. Most will, and should have, direct outs on each channel, the ability to group different channels to
be combined together and sent out the mixing board together (called
"bussing"), auxiliary sends to route the signals to processors, and some sort of VU meter to view the input and output levels.
The mixing board is the central control unit in any recording studio and should be thoroughly researched before deciding on a specific model. If possible, test drive your friend's mixer to learn the in's and out's (no pun intended!) of what you
want before buying your own.
What is a patch bay?
Ever notice that all the input and output jacks for your mixer and effect processors are in the back of the unit where you can't get to them?
A patch bay simply re-reroutes all those ins and outs to a central location so that you can "patch" together all the different devices you need to use. It's a series of jacks that are connected to all your effects and outputs that routes the signals you want just by connecting "jump" cables on your
patchbay. This saves time and makes work a lot more organized.
You can buy them for anywhere from $45 to $185 depending on how many "points" they have. Most start at 48 patch points but can range as high as 128. Buildingone is fairly simple to do, cost less too. See article on "How to Build Your Own Patch Bay"
What is compression?
A compressor controls the level of the signal going into it by reducing the volume of the loud parts, and increasing the volume of the soft parts to make the signal overall more consistent.
Most compressors have 2 variables,
compression, which is how much to compress the signals, and release, which is how long to hold the compression for, the release can be used to increase the sustain of the notes.
Compression is normally used on vocals, bass, and
drums, as well as other instruments as needed. It can be used while recording, or in the final mix down. Most people prefer to run everything "dry" (no compression or other extra effects) into the mixer, use the sends to go out to the effects, and then record, adding the final effects during the mastering.
What is reverb?
Reverb is an effect that changes the original sound from sounding like it was recorded in a closet, into sounding like it was recorded in a gymnasium. It adds depth and ambiance to your music. Most people like to add at least some reverb to the whole mix, to make it sound more full.
What are these -10db and +4db numbers about, and what is balanced and unbalanced?
The real story on line levels is fairly complex, but the quick answer is:
- -10dB level is about 0.3 volts
- + 4dB level is about 1.2 volts
Pro levels are +4, semi-pro and consumer are -10. The original US telephone company signal levels became today's +4; the Japanese consumer-electronics industry began a -10 standard.
Without going into all the impedance and stuff like that, either level is fine, but +4dB lines generally have better noise immunity because the signal level is much hotter. As long as your -10 equipment can handle the higher input level you'll be fine. Prevent overloading it by keeping its input-level set low.
Balanced vs. unbalanced is a different matter: -10 is usually balanced, +4 is usually balanced. Balanced lines offer excellent immunity from hum and noise pickup. This is usually the reason a studio is using +4dB because they want the balanced lines.
An unbalanced line has the "hot" and "ground" wires.
A balanced line contains a "positive" and "negative" (electrically
inverted) copy of the signal (called "hot" and "cold" respectively), plus a shield ground. The receiving-end of the cable inverts the cold and adds it to the hot (assume the "value" of the signal is 1:
N = noise pickup in the cable
hot wire + (- cold wire) = 2
(+1 + N) + (- (-1 + N)) = 2
You end up with a double-voltage signal (the doubling is 6dB of gain). Any noise pick up cancels out neatly.
These are line levels. Mic levels are typically about -50dB, instrument levels are about -20dB (but they can vary widely).
What is the difference between dBu, dBV, dBv, and a dBm?
dBuV and dBmV imply a reference level of one microvolt and one millivolt,
respectively - which are simply not relevant here.
dBu is referenced to 0.775 volts (1 mw into 600 ohms)
dBV is referenced to 1.000 volts (1 mw into 1000 ohms)
dBv is the same as dBu (0.775 volts... just to confuse us)
dBm is the old power reference of 1 mw
Note also that dBm is 10log(P/Pref) while dBu,V,v is 20log(L/Lref). Pro gear indeed has a larger signal - by a large margin (though not 14 dB!)
a X-Y mic'ing setup?
The following was taken from a mailing list posting
>I keep reading about this particular mic technique suited for acoustic
>guitar. Its called the X-Y setup, or something like that. I know it
>involves 2 mic's with different placements, but I am not clear on how
>these are to be set up. If anyone could shed some light on this, it
>would be appreciated.
Sure, it's real simple. It takes two directional mic's and you want them to be as closely matched as possible. By directional, I mean either cardioid or hypercardioid, pickup patterns. Omni won't work for this technique, since it depends on the directional response of the mic to get a stereo effect.
You put the mic's with their capsules as close together as you can get them, and have them pointing at angles to each other, probably in the range of 90-110 degrees apart. So if you're using "pencil style" small diaphragm condenser mic's, you get an
arrangement that looks like a "V" with the capsule ends of the mic's together. Run that into two channels on your console and pan hard left and right.
Having the capsules together like that helps keep the phase of the sound coherent, and then the directionality of the mic's gives you a stereo sound field. You can vary the angle between the mic's to determine how wide the stereo separation sounds.
I've used the X-Y technique for drum overheads and acoustic guitars and it sounds great! You still have to move the mic's around to find the best spot for 'em, but it gives you a nice natural sounding stereo image.
Shawn runs the Home Recording Web site -- a site devoted to home recording projects.
