Recording & Tech Tips
- Why Is This Here?
I started this a few years ago in self defence hoping that everyone would read it before coming into the studio. People were bringing in tracks for mastering and voice overdubs that looked like a lawn mower went over the waveforms - past the point of clipping - and expect to get a clean sounding track.
The other reason was for people coming in to record with no clue about how to get a great recording and with equipment that was in bad shape, drums with worn heads and etc., and a lot of time would get wasted just trying to fix stuff.
- Be Prepared
By that I mean not only be prepared for the session but be prepared to change if something isn't working. Nine time out of ten if something isn't coming together easily it's because the arrangement isn't working. While it's good to practice before going into the studio you also need to be flexible enough to make changes on the spot by playing less to clean up cluttered spots or to play more when needed and etc..
- Have Fun
I have talked about the 3 take rule, which is generally the maximum number of takes that it should take to get a track down and still not lose the feel. There are always exceptions to that rule as in all rules. Some of the best tracks have been made on the very first take. The old blues guys knew that, like Walter Horton who would never do more than one take on a song. If the drummer cracked a stick or guitarist broke a string that was it for that song on that day. Music should be fun so have fun and enjoy playing it and that will come across in the recording.
If you are using drums make sure that all the heads are in good shape. If they are worn the center is usually stretched more then the outer edges of the head and that makes it difficult if not impossible to tune properly. Make sure there are no loose wires on your snare. Also try to eliminate rattles and squeaks. Make sure that all your stands lock correctly so they don't move while playing. This will save you time in the studio. If your drums are dirty from being in garage, barn or etc. please be considerate and clean them so the dirt doesn't end up in expensive microphones. Drums are the hub, the clock of a great track so it's important that the drum track is rock solid. Aside from being the general timekeeper for tempo the time within the drums themselves between the kick, Snare and High Hat must be tight or the track will have a vague loose feel and lack warmth and bottom. Check out the following link for good info on drum tuning.
Drum Tuning Bible - Great Info on Tuning Drums
Bass in general should be tight with the kick drum to create that fat warm bottom end. Listen to the drummer. Check your cords, jacks and controls, wiggle them to make certain they don't make any sudden noises that could show up while playing in an otherwise "perfect" take.
Same as Bass, check your cords, jacks and controls, wiggle them to make certain they don't make any sudden noises that could show up while playing in an otherwise "perfect" take. Make sure all your speakers are in good working order. Also if your using a tube amp check for microphonic (noisy) tubes.
It's a good idea to practice vocals with just a simple instrument such Acoustic Guitar or Keyboard. That will let you hear the vocals without being covered up by the entire band. Aside from having a great song the vocals are the most important part of a track. Tracks with great vocals just grab the listeners ear. Many artist will interrupt power with volume when the sense of real power comes from ensemble, tone and being able to have good vocal control.
In analog it's OK on some material and sometimes useful to go in the "RED ZONE" on the VU meters to produce a fatter sounds. This technique when recorded to analog tape produced a sort of pleasing compression with some instruments such as drums. The "0" on an analog VU meter is the level at which point the recorded sound is generally at optimum and is an average reading which tries to emulate how the human ear perceives how loud something is. There are actually peaks in the sound that can exceed that "0" level by as much as 20 decibels (db) but the meters don't show them. With analog equipment there is overhead built in so it can reproduce peak levels that exceed that "0" level by 14 to 20 db depending on the design, this is the maximum output of that equipment after which heavy distortion usually occurs.
In digital there is no such thing as going into the "RED ZONE" as this would cause severe clipping and distortion. The same optimum level that registered at "0" VU on analog is now at anywhere from -12 to -20 on the digital meters depending on the design of the recording system. The rest of the meter scale is the overhead up to "0" (Full Scale), over that is clipping (severe distortion). These digital meters read peaks, the maximum level as opposed to analog VU meters which read the average. Getting a fat sound is done another way by use of tube preamps and compressors or by using specialized software plug-ins.
- The Reference Level
The "Reference Level" is important to know something about. It is the point of optimum level, the best compromise between noise and distortion on analog and having enough overhead for peaks in digital. Digital systems vary depending on their design. The reference level could be from -12 to -20 below "0". Only a pure tone, a sine wave, will read accurately on both digital and analog since there are no peaks in a sine wave. So if you feed a "0" VU level out of an analog mixer into a digital recorder it should read -12 to -20 depending on the design of the digital system. Likewise if you send a sine wave out of a digital system at -12 to -20 it should read "0" VU on your analog meter. Sending a "0" level signal out of digital into analog will most likely cause the analog equipment to distort. My Protools system for instance is set at a reference level of -18, which means a sine wave at -18 feeding analog equipment with a VU meter will read "0" vu on the analog meter. You need to check your manual that came with your recording system to determine the correct reference level for your equipment. Now there are also variations in equipment outputs and you need to pay attention to that. Most Pro Studio equipment operates at +4 db output when the meter reads "0".
Non professional equipment operates at -10 db when the VU meter reads "0". In order that everything matches level wise you need to make sure everything that is connected together operates at the same level. Some equipment has two sets of inputs and/or outputs, one at +4 and the other at -10. A +4 out must feed a +4 in and like wise a -10 out must feed a -10 in. A level matching converter can be used between 2 units if they are mismatched and you don't have output or input level options.
- The Levels To Shoot For
When recording you can never go wrong if you aim for an average level around the reference level and occasional peaks at -6 or below. When mixing shoot for a maximum level of -6 for your mix buss level. I get digital recordings to master that are through the roof at "0". They've already been clipped. The waveform looks like a lawn mower went over the top of them. Everyone is so worried about their record sounding as loud as the next guy that they push the levels past clipping trying to get there, but that's what mastering is for. A good mastering engineer can make it sound loud without clipping.
- Why Do I Need To Record So Low In A Digital System?
Well suppose you recorded a sound at "0" or even -3 and wanted to add 6 decibels of EQ, 6 db plus 0 or even -3 is +6 or +3 which doesn't exist, a glass can only be filled to the top-not more, you are now clipping the peaks by that much and causing distortion. Distortion in digital is not nice and rarely wanted If you have many tracks to mix together the sum of the levels is more that the highest level recorded which can be over the "0" level.
Mastering is the stage where the maximum level is set. If you mix at "0" there is no room to go anywhere, you can't restore the clipped waveforms and levels will need to be dropped before any additive EQ can take place and then boosted again causing unnecessary manipulation of the audio.
- What about Noise?
In a 24 bit system the usable dynamic range (the range between noise at the lowest levels and distortiion at the highest) is about 144 db. The best Digital converters have a range of about 120 db, your world class mic preamps around 90 db or so and analog tape about 72 db. Even a 16 bit system and CD audio is around 96 db. For every bit you add the dynamic range doubles, 6 db per bit. So even at -18dbfs (18 db below full scale or below 0) in a 24 bit system you still have 126 db of very usable dynamic range. Much higher noise levels from Room noise, Mic noise, Preamp noise, Instrument noise and Guitar amp noise far exeed any noise from the recording system.
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