Practical Speaker Tips

Let's face it: when it comes to speakers, there isn't much new you can say about a technology that has remained more or less unchanged for several decades. Sure, we now have better tweeters, computer-aided design for speaker cabinets, and other touches; but we're still pouring gobs of current through mechanical devices that end up pushing air. So, let's assume that you understand speaker basics, and instead concentrate on some practical tips and techniques that will help you get the most out of your speakers in mixing and recording applications.

TWO SPEAKERS ARE BETTER THAN ONE

Speakers aren't perfect, and neither are listening environments. Therefore, as you mix sometimes it's better to switch between different sets of speakers to get an idea of an "average," rather than idealized, sound. For example, in my own studio I have a pair of good quality, neutral response speakers that reproduce sound very accurately. But I also have a couple of little Auratone cubes, which sound much more like the speakers found in portable tape players, televisions, and car radios. When setting up to record a sound or mix, I'll usually do the preliminaries on the Auratones, then switch over to the main speakers (which is like putting the sound under a microscope) and make any necessary tweaks. As a rule, if something sounds good on the Auratones, it almost invariably sounds great over the big speakers...but the reverse is not necessarily true.

DON'T OVERLOOK HEADPHONES

Many people wonder about using headphones for monitoring. Sealed-ear types are fine for cueing and overdubbing (don't use open-air types as they tend to have a more deceptive bass response), but for mixdown, where all sounds are super-critically evaluated, you also need speakers. More people listen to music over speakers than through headphones, and a piece of music mixed on headphones will tend to sound best only when played back through headphones. In addition, headphones sometimes reveal more than they should. For example, what sounds like a bit too much reverb on headphones can seem excessively soft on speakers.

Still, I use headphones a lot during the preliminary stages of a mix so that I can hear little problems, like clicks or hums; and by sealing out the effects of the room, it's possible to get yet another "reality check" on your sound. Hint: When listening critically, press the earcups lightly against your head for as good a seal as possible. This gives the maximum bass coupling into your ear.

NEAR-FIELD MONITORING

The most common use of monitor speakers in the budget studio is near-field monitoring. This simply means you have the speakers mounted only a few feet away from your ear so that you get mostly direct sound and very little reflected sound; the minimizes the extent to which room acoustics affect the sound.

If you use hi-fi speakers as near-field speakers, for best results mount them horizontally, not vertically, with the tweeters at the extreme left and right sides and the woofers in the middle. The speakers should also face inwards slightly. When mounted this way, the highs (which are directional) have maximum separation, while the low frequencies (which aren't so directional) emanate more from the middle.

THE ULTIMATE REALITY CHECK

The ultimate reality check is to book an hour of studio time at a world-class studio, then play your final audio mix over their system. Before doing that, though, listen to your audio so many times on your own system--paying particular attention to the overall frequency response--that you know it totally by heart. As you listen to the tape in the pro-level studio, the music should sound like it did back in your studio. If there are differences (i.e., boomy bass, overly "zingy" high end), note these.

If there is a consistent difference between what you thought your audio sounded like and what it sounds like on other systems, take this into account next time you record or mix. For example, if your tapes sound bass-heavy on other systems, back off a bit on the bass when working in your own studio. (Incidentally, since you've already booked the time, you might as well run off a safety copy of your tape on one of the studio's tape machines. In fact, if your tape really does sound wrong when played back over a super-accurate system, you might be able to equalize or otherwise alter the copy to produce a copy tape that's better than the original.)

TO ROOM TUNE OR NOT TO TUNE?

Ideally, your monitor speaker should live in a totally flat listening room. However, this simply isn't possible; every room exhibits a variety of response anomalies.

To check the room response, a sound level meter is ideal. Budget models are often available for around $40-$50. They consist of a flat response microphone connected to a level meter. You run several different tones through your system, then monitor their levels in the location where you'll be listening to your speakers. Prepare yourself for a shock when you do this; room responses are anything but flat, and drawing a graph of the levels of the various tones will probably look like a picture of the Alps.

If you have some problems with your room (as determined by the above test) and want to improve matters, you might be tempted to flirt with perfection and try to "tune" the room using a multi-band room-tuning equalizer. This process involves pumping a pink noise source (which exhibits constant energy per octave) through your loudspeakers, then picking up the signal with a precisely calibrated microphone. The mic output feeds into the multi-band equalizer, which then tells you whether the response for a particular band is high or low compared to the other bands. You then vary the equalizer controls to "tune out" these differences. For example, if the highs seem somewhat anemic, you can boost the equalizer's high frequency bands to compensate.

Concerning hardware, room tuners can be anything from microprocessor-controlled wonder boxes that do all the work for you to relatively simple devices that have "high," "low," or "correct" LEDs for each band (you simply adjust the equalizer controls until only the "correct" LEDs are on). But as you might expect, nothing is perfect and the room tuning process involves certain tradeoffs. Generally, if you use equalization to tune a room, you are tuning it for that one place where the calibrated microphone sits. Even if the room seems perfectly tuned, if you move the mic a couple of feet in another direction the frequency response will change.

In my opinion, room tuning must be done carefully. Just like Anderton's First Law of Noise Reduction ("noise reduction works best on signals with very little noise"), room tuning seems to work best with rooms that are already have pretty good acoustics. In other words, if you have a bad-sounding room with poor speakers, all a room equalizer will do is give you a highly equalized bad-sounding room with poor speakers. This may represent an improvement, but as noted earlier this improvement may only be apparent to listeners in certain selected areas of the room. On the other hand, if your room already sounds good, adding a few dB of boost or cut here and there can turn a good room into a very good room.

GETTING RID OF RESONANCES

There's one more thing we need to do, and that's make sure that they're aren't any sympathetic vibrations resonating along with the speakers. For example, after spending months installing a brand new isolation booth and speaker mounting system in my studio, I played some drum tapes to hear how the room sounded. It was great--the sound was consistent no matter where I stood in the room, but...what was that strange ringing noise? After a few moments of panic, I started zeroing in on the source of the resonance, which (thankfully) had nothing to do with the room. Instead, the metal bottom panel on one of the rack mount cases was vibrating whenever a signal occurred around 300 Hz. I wedged a piece of carpet between the panel and casing to deaden the sound, and all was well.

There's a simple way to find resonances in a room. Use a low distortion sine wave oscillator (a keyboard synthesizer-generated sine wave will also do) and plug it into your board. Then, sweep from 20 Hz to 20 kHz at varying volume levels. Listen for any buzzes that indicate loose screws, vibrating surfaces, or similar problems, then do whatever is necessary to fix the problem. For example, if a panel is vibrating, glue some heavy material on it to help inhibit any tendencies toward vibration.

So there you have it...a bunch of speaker-related tips. In closing, remember that a system is only as good as its weakest link: If you want to produce quality audio, make sure that every element of your system is oriented towards quality.

REMEMBER THIS IS THE MUSIC BUSINESS
IF YOU DONT INVEST IN YOUR CAREER, NO ONE ELSE WILL !!!