CWMEA University of Washington
Recording Workshop, Nov 15, 2003
Gary Louie, UW School of Music

Basic recording of your traditional ensemble.

What we do at the UW - balance/compromise of cost and performance.
	-Record in the performance hall
	-Stick to CD quality digital recording for now - DAT with built-in pro mic inputs ($1500)
	-Start with a stereo pair - A-B omnis or ORTF cardioids - Neumann small condensor mics ($1200), balanced cables.
	-Mics hung from catwalk. Could use a big stand if looks don't count
	-Additional spot mics added if absolutely neccesary (concerto). If not, no mixer needed!
	-DAT copied to computer, edited into CDs.

There is a school of thought that thinks dozens of microphones should be used, all separately recorded on multitrack recorders, later mixed down to stereo. We don't have the time or budget to do that and you probably don't either. Nor is it neccessary.


(Review)

Room: More important than most realize for traditional/classical ensembles.
	Better off recording in a performance hall; the hall sound is part of the recording. Recording in band room=sounds like recording in band room, even if you add artifical reverb later. No room reverb to smooth out the sound as expected by listeners. Avoid if possible, especially for competition. Avoid too much room (gymnasium), although closer miking may minimize the problem.


Equipment: 

Recorder- We stick to stereo for now, it's very universal.
	Picking a recorder. We have chosen a DAT recorder because when we began digital recording, it was the first format that offered what we wanted (except perhaps archival stability). CD quality, 2 hour recording time, portability, decent professional mic preamps with 48v Phantom mic power. We use the Tascam DAP-1. DAT nearing end of its life cycle.
	CD-R recorders are OK. Media is cheap. (we've had some problems, blanks not recognized, recordings won't finalize, 80 min. time limit, won't play in other machines). Advantage of easy ripping into a computer for editing and copying when it does work.
	MiniDisc pretty good (Only in SP mode) - digital compression similar to high quality MP3. But DAT and CDR have no compression (maybe a bit better).
	Cassette (not so good)
	New digital technologies and formats - adapter box into computer; portable hard drive recorders, portable CDR recorders, flash memory drive recorders (iPods and such). 

If the recorder does not have good mic inputs, you can add a mic preamp or mixer.
Lots of otherwise good recording devices have no mic inputs, like a CDR recorder. So we add a mic preamp or mixer to allow using good mics.


Your primary problem, even if the recorder itself is capable of CD or near CD quality recording , is getting a good microphone signal into the recorder.


Getting a Good Microphone Signal into a Recorder:

You may have to settle for a $100 stereo microphone directly into a MiniDisc recorder mic jack, or you may be able to afford 2 nice condensor mics and a mixer/mic preamp into the line level input of a digital recorder of some sort (optimal), but you still have to deal with the same problem - matching the microphone signal to the microphone preamplifier (which may be inside the recorder) and avoid electronic overload. Doing this properly is the little known audio engineer's secret.


Here is the problem:
-You have a very loud band; microphone handles it OK, but sends hot signal to microphone preamp, which was designed for average-medium loud sounds only. Overloads preamp, causing "clipping" on louder sounds. Clipped sounds from microphone preamp are sent to the recording level control on the recorder, so even if you reduce the recording level, you are just recording an already distorted signal but at a lower level.

Enter: the mic pad (level reducer) or mixer "trim" or "gain" control. You must reduce the level of the mic somewhere before the mic preamplifier to prevent overdriving it. Pads are on mics, on mic preamps/recorders, and available as accessories. 10dB/20dB common. If you have mic preamp clip LEDs, so much the better. Otherwise, guesstimate or test. If the record level control has to be cracked less than 2/10, pad until you can turn the record level to more like 6 or 7 on the loudest sounds. If you overdo the padding, you won't be able to let the loudest parts of the music hit the recorder's maximum (0 dB on a digital recorder) and you have a hissy noise problem to various degrees.

Fact: slightly clipped music is not always so easily heard as clipped/distorted, and it sounds louder. So a little over recording may be OK.

[Play CD examples]

I do not use limiters or compressors, I attempt to set the recording level so the loudest sound gets as close to digital zero as possible without going over.  Some experience with the music, the hall and the recorder/mics/mic pres at work here. Analog meters are usually different.


Picking the mic

No such thing as the perfect mic, they all have compromises and sound different. We use small (3/4 inch) diaphram Neumann cardioids (directional) and omnis (non directional) as they are reasonably priced for pro mics ($600 each) and work beautifully. I have also seen $100 mics that sound OK, and $300 mics that don't sound as good as the $100 mics.

A condensor mic made for general recording is preferred over a dynamic PA or vocal mic, which is usually made for robustness and vocal coloration.

The small, $100 battery powered stereo Mini recorder mics can be OK, if you position it properly and pay attention to the preamp level problem.

Next step, probably the $250 stereo mic, typically battery powered.

Next, probably starting to get to copies of well known mics like the German Neumann for about $300 each, with professional balanced connectors (XLR) and industry standard Phantom 48 volt powering. Phantom power runs the microphone's electronics through a voltage delivered through the microphone cable from the mic input connector. A worldwide pro standard.


Cobbling together a System
	-mini stereo mic into a MiniDisc or cassette recorder
	-Upgrade to AT822 - still miniplug
	-Upgrade to AT825 - XLR and balanced cables. Either get a recorder that accepts XLR mics, or get a mic preamp and some recorder with "Line" inputs (DAT/CD-R/MiniDisc/cassette)
	-Battery power or P48?
	-Studio grade mics need XLR, P48



The Stereo Pairs: Well studied techniques work well
	A-B spaced omnis - 6ish feet apart. Brighter sounding on axis; when hung, pointing down is normal. If on stands, try pointing them various directions. Good omni mics have the best transient response and smoothest sound, and pick up room reverb (good if room is good).

	ORTF - French acronym, near coincident cardioids splayed 120 degrees and about a human head width apart at the diaphram. Works very well under wide variety of conditions. 

	If you have a mixer, you can add soloist mics judiciously. I don't do it unless there is a concerto, really adds complications.


Mic Positioning:

Anyone taped from the audience? Sounds bad on the tape, although you thought you heard it fine yourself. This is psychoacoustic. So partly from traditional expectation of other recordings, and partly psychoacoustics, we will try to make a recording that tries to fulfill the expectations of what people THOUGHT they heard in the audience.

Start with a stereo pair, either A-B spaced omnis or ORTF near coincident cardioids.
Elevate the mics above and behind the conductor for starters. The idea is to get a natural balance of the instruments, which are probably already arranged for tradition reasons - it sounds good already to the conductor. However, not everyone wants to really hear what the conductor is hearing, so we fudge. In a typical hall, we'll be 10 feet above the conductor and a few feet behind. Too low, and it favors the instruments downstage. They like this, however.  Some conductors (Gerard Schwarz) have been known to move sections around a bit to get a better balance. 

Evaluate. This is partially your opinion. Too distant? Too close? Move the mics. Too much flutes? Maybe raise the mics and point them over the the flutes.

Don't place mic on a chair, floor or against walls as the sound reflections may do weird things and the balance will likely be poor. 

Someone asked about the difference between recording a performance and recording session. I'd say the difference is that in a session, ugly stands and cables are OK, and in a performance they are not. Otherwise, the same objectives for placement of mics holds.


Monitoring:
headphones: things will sound closer than when heard through speakers. 
	level will be low unless you are perfect at setting level. One reason for normalizing on the computer.


Start with a basic stereo pair
Pay careful attention to mic preamp overload/pads
Do not start the recorder late.




Camcorders? Unfortunately, no consumer cameras allow adding good mics and long cables, they all have mini jacks. You will never get a decent soundtrack on a camcorder. 
Next step, Beachtek-style adapter (still working into a cheesy mic input).