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Monday, January 6, 2014

Creative Use Of Effects

Tips & Tricks

Technique : Effects / Processing

All recording setups incorporate effects devices of one sort or another, but it's easy to end up using them in the same predictable ways. Roger Jackson introduces some more imaginative ways to freshen up your productions.

A long as I can remember, effects have been used in an attempt to improve the sound of music recording and performance. Possibly the first such use was when monks discovered that plainsong, which is the forerunner of all classical music, sounded better when it was sung in a large stone monastery, rather than a small rehearsal room -- not that I have first-hand experience of this, you understand!
In the '60s, guitar amps started to feature tremolo, as well as the dreaded spring reverb, which produced some particularly unusual effects if the amp was placed anywhere near the drum kit. Then there came a period when effects were created by engineers using conventional studio equipment in unconventional ways. These tricks created tape echo, phasing, flanging and chorus effects, all produced by varying tape speeds and applying controlled feedback with varying degrees of success.

Today, the recording engineer and producer have a massive array of digital effects with which to enhance (or ruin) the music, but there is still scope for innovation. It's useful to remember that recording is the only situation where the end justifies the means -- that is, whatever recording conventions you break are unimportant so long as the CD goes gold (not that it's OK to go out and steal a vintage Neve!). It's also useful to beware of what has become known as 'Babes In Toyland' syndrome, whereby it's considered to be wasteful if not all the available effects are used all the time. In fact, the complete absence of effects can be used as a technique in its own right -- see 'Staying Dry' elsewhere in this article.
Nothing to do with concealing baldness, but a means of creating stereo from a monophonic source. A comb filter can be used to divide the frequency spectrum into many small bands, and place alternate bands to the left and right of the stereo field. It produces an effect not unlike stereo chorus, but possibly more coherent. It can be used on almost anything from a solo instrument to a full mix, depending on the effect required. A useful feature of this form of stereo synthesis is that it is mono compatible, unlike many time- and pitch-based effects. Some effects units provide a comb filter, but these tend to be in the higher price range. It's possible, however, to produce a crude comb filter with a graphic equaliser, and whilst this might not be so effective on a mix, it can be very useful on guitar chords and keyboard pads. The best graphics to use are third-octave stereo devices -- in other words, the ones with lots of sliders -- but almost any stereo graphic will produce some effect. Connect the mono signal to both inputs of the stereo graphic and then position the sliders as follows. Start with the left channel and the highest frequency band and move the slider to full boost. Then move down the frequencies and cut and boost alternate bands. Moving to the right channel, cut the highest frequency and then boost and cut alternate bands. If you've not made any mistakes, each frequency band should have one side of the stereo boosted and the other side cut, and these should swap over as the frequencies descend. For maximum effect, only the signal from the graphic outputs should be used, so care should be taken to avoid routing the original signal to the mix.

Some of the most successful effects are the ones which subtly and generally improve the sound without the listener being aware that an effect has been used. Aural enhancers are typical of this category: because they simply enhance the recording without radically changing the character of the sound, they can be used on virtually every track. Flangers, on the other hand, are definitely of the other kind. It may have been innovative when the Small Faces used one on 'Lazy Sunday' and the Eagles put it on the end of 'Life In The Fast Lane', but there seems to be a tendency at the moment for bands to shove the effect onto a protracted instrumental section at the end of every song. The words 'death' and 'done to' spring to mind.

Open The Valves

When we're looking for effects which change the character of the sound, rather than stamping a whole new personality onto it, valve-based processors (employed carefully) can be useful. However, as a valve processor can cost as much as the 8-track hard disk system on which you're recording, this may not seem a realistic option. At this stage, it's useful to remember that lots of guitar amps have valves in and, whilst you might not want to stuff your digital stereo master through a pair of old Marshall stacks, individual tracks might well benefit from this type of treatment. I regularly take vocal tracks which have been recorded using a Neuman U87 and 'posh' desk and feed the signal through a small valve practice amp, picking up the result from the direct-out jack. There can be no argument that the total harmonic distortion figure becomes degraded -- I believe the technical term is 'shot to hell' -- but engineers who don't know what I've done have complemented me on the live feel, and if the song is largely guitar-based, the processed vocal is so much easier to mix than the clinically clean digital version.

It follows that almost any track can be given the same treatment and similarly, it follows that almost any amplifier can be used as the processor. Every amp will have its own character, and there's no rule that says it has to be designed for guitars (though before plugging anything, particularly guitars, into strange amplifiers, please read the section on 'Staying Alive'). The same can be said for speakers, and experimenting with different combinations and different instruments can prove very rewarding.

Among my own stock of effects processors you'll find a Bush valve radiogram, a 5W, British-made, discrete transistor amplifier of uncertain origin and purpose (for which I've refused vast sums of hard cash, due to its particularly rich and individual sound) and a 12-inch speaker out of an old Hammond organ. Basically, by using all this strange equipment to process my recordings, I'm corrupting the sound, but in a way which I find pleasing. This is not an exact science, but one founded on empirical results -- that is, if it works I use it again, if not, then all I've lost is a little time. For example, I've found that computer-generated drum tracks can sound fine with clean digital keyboard tracks, but can sound too perfect for mixing with overdriven guitars. My solution is to pass the drum track through the aforementioned transistor amp and the Hammond speaker. The amp imparts a warm, thicker character to the sound, whilst the 12-inch speaker appears to act as a band-pass filter, giving a result which is undoubtably distorted but much easier to work with in the mix.
"Using a battery-driven 4-track cassette recorder, I've placed a drum kit in an underground car park for the best large hall you've ever heard, and also in the open air for a complete absence of room effect."

The Bush radiogram puts in a lot of service as a guitar amp and, whilst it's not the sort of thing I'd like to be seen with on stage, it produces an unparalleled sound for lead guitar solos. By using the input which was originally intended for the record deck (those things which used to play plastic discs), the sensitivity is such that the guitar will overdrive the amp into gentle distortion. Record-deck inputs have built-in RIAA equalisation, which by a happy accident, seems to suit a Strat on the middle pickup perfectly!

Get It Taped

There is an argument which says analogue tape is better than digital recording, and the number of studios which are thriving on the use of two-inch 16- and 24-track machines must give a certain amount of credibility to this claim. I prefer to think that each has its merits, and that what instruments are being recorded makes a difference to the choice. If you like the sound of analogue, an old stereo machine is all you need to bounce digital tracks on and off, to achieve tape saturation at a fraction of the cost of a processor which simulates the same thing: simply use one track for timecode and the other for the signal. But tape has even more creative uses, and if you have an old 4-track, or even a cassette multitracker, the possibilities are increased; not only can you get that vintage tape sound, but you can go on location and use real reverb and room simulation.

Let's suppose you want a vocal reverb without digital artifacts, one which will tail away without breaking up, one just like the church hall down the road. All you need to do is record timecode on to track one, leave track two as a guard (particularly important for cassette formats where crosstalk can be a problem), put a mono mix of the backing on to track three and take the machine down to the church hall, along with a microphone and a set of headphones. Record the vocal on track four and then, back in the studio, bounce this track back into the format you first started with. (Of course, if you want the reverb without the tape saturation, you could save time and hassle by just taking your digital recorder to the hall!)
Staying Alive
All amplifiers have the potential to kill -- even if the current is not great enough to electrocute, any electric shock can disrupt the rhythm of the heart and cause death through heart failure. When you consider that the strings on most electric guitars are connected to the circuit ground, and that some old valve equipment runs at many hundreds of volts and features idiosyncratic earthing systems not designed with guitarists in mind, then the need for care becomes apparent. To avoid a bad case of death, get all equipment checked over by a qualified technician prior to use, and then use a transformer-isolated direct injection box between the source and the amp. Under no circumstances should guitars be plugged into microphone sockets which carry phantom power.

This same technique can be useful for location recording of loud signals, such as guitar solos which rely heavily on feedback and live drum kits, which are problematic in a bedroom or garage studio. With care, the mono mix can be recorded at a lower level next to the timecode track and this will serve as the guard track as well, leaving two tracks free for stereo recording. I've successfully used this method to record live drums to replace a drum machine in a final mix and, as a bonus, found real rooms which were better than anything in my effects units. Using a battery-driven 4-track cassette recorder, I've placed a drum kit in an underground car park for the best large hall you've ever heard, and also in the open air for a complete absence of room effect.

Mic Me Up, Scotty

Anything which colours the sound of an instrument or voice can be used as an effect, and so it follows that there is scope for innovation in microphone choice and placement. My favourite mic for the last ten years has been a U87, which I'm inclined to use on almost anything and everything -- but only when I'm after clean, faithful reproduction. My mic box also contains, at the other end of the scale, a 30-year-old Reslo ribbon mic, which was bought at a car boot sale for two pounds. It's impossible to describe the sound which this relic imparts to the recording, but faithful reproduction doesn't come into it -- and yet, if you want that particular effect, there's no other way to obtain it. The moral of this tale is to experiment and to break a few rules in search of that elusive 'something different'. Try a few of these for starters:
  • Use a free-standing PZM boundary mic for recording vocals.
  • Use a cheap and nasty crystal mic, heavily gated, on a snare drum.
  • Cut a hole in the bottom of a bucket (galvanised metal is best) and place a dynamic mic through the hole from the outside. Point at guitar amps.
  • Place a chassis speaker and a microphone in a large cardboard box. Feed almost anything through the speaker to be picked up again by the mic. Produces a surprisingly boxy sound!
  • Stand in front of a live drum kit swinging a dynamic mic on an anchored cable like a propeller in front of you. I've never dared try this one, but I've heard the results and they are quite unsettling.
Finally, a couple of things which you can do to a stereo master:

Staying Dry
Most music has some effects; even that which sounds dry will almost certainly have a small room reverb on parts of the mix, so leaving out all effects and reverb will certainly make a track sound different. To get the best out of this technique, as many instruments as possible need to be direct injected to avoid recording any ambient sound from the room, and this means, of course, that computer drums are often more appropriate than a live kit. Guitarists are often reluctant to DI for various reasons, usually associated with the sound of a favourite amp and the fact that it's impossible to get feedback when plugged straight into the desk. However, many amps have a direct output which can be used instead of a mic, preserving the basic sound and permitting feedback, whilst peeling off the high and low EQ on the desk will help to simulate the effect of a speaker cabinet. Keyboard sounds should be free from built-in effects, particularly reverb and chorus. Recording live sounds is more difficult, and care should be taken to record in a well-damped and dry environment. Place the mic closer than you would normally expect for studio use, more like a live performance, and use a good pop shield to avoid breath noise when recording vocals. When it comes to mixing this type of track, stereo imaging is all-important. Without the smearing which results from the use of time-based stereo effects, instruments can be placed in the stereo field with great accuracy and to great effect. Pay particular attention to the spread of the drum kit and any extra percussion, to widen the stereo image. The finished result should have more punch and will appear to be louder than conventionally recorded tracks -- reverb has the subjective effect of making the music sound further away and, therefore, quieter. Tracks containing reverb can sound fine in the control room yet suffer when played in a large club, which effectively adds more reverb, but a dry track will excel under the same conditions. If you are looking for the ultimate 'in-yer-face' mix, which is different enough to catch the attention of A&R people, this could be the way.

In the (good?) old days, when the Beeb wouldn't play cassettes on the radio, we used to put cassette recordings through a graphic equaliser to remove all the hiss and then through an Aphex Aural Exciter to replace the top end, mastering the result on to quarter-inch reel-to-reel. I can't remember ever having one rejected! (For other uses of a graphic, see the 'Comb-over' box.) In fact, the technique works so well that I still use it on digital masters which have a brittle top end. Quite often, the synthesized top end is smoother than the original.

Never being one to shrink from controversy, I'll dare to raise the issue of digital compression. Can you hear the difference between DAT and Minidisc? Well, in addition to the group which says 'no' and the group which says 'yes', there's now a new group (well, me actually) which says 'yes and Minidisc is better!' The compression technique used by Minidisc looks at the program material and leaves out anything which it reckons you wouldn't hear anyway. It's a bit like when you don't hear the telephone because the stereo's up too loud: it still rings, no one answers it, so it just clutters up the music. I can hear a difference with Minidisc, but to my mind, it makes the music cleaner, more transparent and easier to listen to. This could not only be the mastering system of the future, but the ultimate effects processor for your old DAT tapes!

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