Well, we’ve covered a huge amount of processing devices and techniques in the last week. There’s still a huge amount to go, which is totally awesome!
I’ve posted over 25,000 words this week alone, all discussing just three very broad categories of effects, namely delay, reverb and modulation effects.
In today’s blogpost I’ll review all the other processing techniques that don’t fit neatly into the categories of delay, modulation or reverb, although, inevitably, there is some overlap with these areas in most of the processes described in today’s blog.
New categories of effects seem to appear every other week. Hurray!
Recent plug-ins I particularly like include the UAD Ocean Way Studios “room emulation” plug-in recently debuted by Universal Audio for their excellent UAD-2 platform. This is a new breed of complex software. It allows you to place your instruments or vocals into a virtual model of the legendary Ocean Way Studio A or Studio B, and then place virtual microphones around the virtual room as desired, moving them where you want them.
Then, another new favourite is again from Universal Audio, Inc.
It’s their plug-in model of mastering guru Bob Katz’s hardware K-Stereo Ambience Recovery processor, which they have emulated in software and placed into their Precision family of mastering plug-ins, all of which are very well realized and powerful tools.
Also, of course, we have long had pitch correction products like the ever-popular and mature classics Antares Auto-Tune+Time and Celemony’s excellent rival offering Melodyne, both of which are fantastic plug-ins, each with their own unique strengths and processor tonality/colouration side effects.
With Auto-Tune, changing tonality of input signals to that nasal sound we all know (and love?) is not so much a side effect as a deliberate move.
People mostly seem to like the change in character it brings to a vocal, and we’ve all come to expect to hear the type of perfectly pitched vocals of which Adam Levine is a fine exponent. It’s a cool sound, although perhaps rather overdone a lot of the time. It has it’s place.
We have pitch shifters and harmonizers. These have been around for 35 years or more now, and can add texture, depth and width to sounds, while simultaneously giving them additional motion within the mix, engaging the listener more persistently.
We have time-stretch functions in software products of various kinds, many of which are virtually transparent in operation if you are only making relatively small changes.
In fact, at least some pitch and time features are always included with virtually all DAW software sequencer/recorders, at least for laptops or desktops.
Sampling-friendly products like Ableton Live have built a significant market share in sequencing platforms due to their fantastic ease of operation and their ability to facilitate live triggering of samples on the fly.
They offer pitch and time correction features that are astounding in comparison to what was available in the not-so-distant days when analog 24-track 2″ tape machines roamed the Earth and editing audio meant wielding a razor blade.
How about some distortion processors? Tape emulation? Spectral granular processing? Multiband exciters? Amp and speaker emulation? It’s surprising how many types of effects there are when you think about it.
EXCITERS AND ENHANCERS
The Aphex Aural Exciter introduced the idea of the exciter in 1975, and it’s probably the first processor specifically designed to add distortion to gain a perceived improvement in quality, an idea that ran contrary to the very notion of hi-fi audio in the mid-1970’s.
It went on to see mainstream use in recording studios very quickly. Some of the products in this area now call themselves enhancers, but they seem to me to be interchangeable. The patents protecting these products tend to obscure how it is done. However, it’s not hard to see it’s a combination of enhanced levels, better stereo imaging, dynamic EQ, phase rotation, and most of all, adding new harmonics to the source that were not present in the original. This last function is it’s most impressive and important characteristic.
The Aphex Aural Exciter was a sealed unit, and the process itself, which was said to be an accidental discovery made courtesy of a faulty amp channel, was protected as a valuable trade secret. In fact, the exciter is essentially a distortion processor, and today you will find plug-ins that offer multiband exciters and multiband distortion amongst their feature set, such as Izotope Ozone, a processing leviathan I can recommend for a home studio without reservation. The full Ozone 5 Advanced package is superb and very comprehensive for both multiple effects and essential metering plug-ins, but pretty expensive at somewhere around 700 bucks US.
The Aphex Aural Exciter was mentioned by name in the credits on numerous hit records (for example, Linda Ronstadt’s gorgeous 1970’s album “Heart like A Wheel”), and the Aphex unit became a very popular processor in studios everywhere in part due to very high public visibility (for recording gear!) coupled with a decidedly proprietary business model.
It really did make voices or acoustic guitars sound a bit better in small doses, but there was a fine line between making a genuine improvement and, at the opposite extreme, adding a distorted, fried, wasp-like sound character to the upper mids and, more obviously, to the highs of your source. A dangerous weapon, then.
The light airy fizz of the slightly overdriven exciter of the 1970’s was put to very good use on many a double-tracked acoustic guitar submix, and, most often, lightly sprinkled over the lead vocals (but not on the background vocals, so as to keep attention focused on that all-important lead vocal).
The exciter always makes things brighter, as you would guess from the name. It’s important to understand that it doesn’t do it by adding treble EQ. There are several types of exciter process and each is somewhat differently achieved, again the subject of patents for the most part.
Exciters in general work by adding various harmonics that were not present in the original signal, creating subtle amounts of HF distortion, and these are blended to taste.
The sound is rather “airy” and somewhat reminiscent of comb-filtering’s sum and difference characteristics, so I think there’s probably some multiband phase rotation going on there as well, or at least dynamic EQ changes that could cause phase shifts (“smearing“) as a side effect.
Most people overdo the processing. Please don’t. It’s way too easy to screw this up, and you WILL regret it later.
EXCITER AND ENHANCER CONTROLS
Enhancers are capable, in many cases, of dealing with bass signals effectively, not just midrange sounds that need brightening.
There will be a Frequency control so you can choose the frequency at which the exciter will start processing.
There will also be a Mix or Effect Balance or Ratio control to balance the amount of effect mixed in.
There is always a Drive or Gain or Input control that increases how much of the effect is to be introduced to the signal, and turning it up adds more and more new harmonics and distortion artifacts.
The sound soon becomes rather thin and disembodied, with a wispy, airy quality. It can be downright thin and fizzy at the extremes.
Within a very short space of time, it becomes extremely fatiguing to the ear to try to monitor how much processing is occurring. This is the classic trap you will fall into if you don’t act deliberately and carefully with any exciter processing, taking regular breaks and A/B-ing the effect on and off at equal playback volumes to neutralize any listening bias.
Be extremely careful. It is typical to find after a good break from listening to your mix in progress that you need to back off where you think the Drive should be, and by a very long way. This is essentially a destructive process that works to add magic to lead vocals in particular, but
Overused, it is really quite damaging to audio signals, but in small amounts it adds a certain sparkle. The trick is to use a light dusting of the effect across tracks like vocals and acoustic guitars, that have some clear mids and high end air to them. The exciter adds various artificially-generated harmonics to the signal which can be irritating to headphone listeners in particular, so less really is more in this case.
Carefully adding enhancement to every sound in the mix can make every sound seem slightly better, when heard in isolation. In respect to each other, however, no improvement is found. There is only one way to use enhancement in a mix with success, and that is to enhance or excite only one or two tracks at most. The addition of extra harmonics can, of course, increase masking of other instruments at those frequencies, so it’s an area in which to tread very, very carefully.
Other processes like equalization, compression or distortion itself may be more useful than an enhancer or exciter, depending on the reasons you have for trying to enhance the signal.
The name of the game here is subtlety, and, like so many other mix processes, it works best if you treat it like adding salt to food. A pinch can bring things alive, but pouring it on thick will ruin the meal.
DISTORTION PROCESSORS AND AMP SIMULATIONS
The exciters and enhancers are a special class of distortion processor , but there are boatloads of other distortion processes available out there.
They range from old-school bit-crushers to devastating distortion guitar pedals to plug-ins that can model very small and badly damaged speakers.
The times are so cool for audio geeks, it’s beyond ridiculous.
The difference between real guitar amplifiers and plug-ins is getting more and more subtle all the time, and in many cases you can safely use a plug-in rather than a guitar amp. It’s certainly more neighbour-friendly to use an amp plug-in, and it is vastly more flexible. The real amp still wins, however, and the addition of actual room sound at the microphone counts for a lot.
A re-amping box like Radial’s X-Amp will allow you to do the same trick as the EXTC, sending DAW signals out at line level, converting them to Instrument Level and sending them on to a pedal/amp chain. Using X-Amp, you don’t return the signal to the DAW via the X-Amp. It’s intended to be used with an amp, so you mic up the amp and record that.
This is a fantastic way to deal with the issue of selecting amps, since they can be picked to compliment other sounds you already know are destined for the mix, but there is a subtle difference that great players can feel, and the interplay between the guitar pickups and a real amp/speaker affects the player’s feel.
When you use the X-Amp method, the player has already done the playing, and it’s a recording you are sending to the amp, meaning the amp/guitar interaction is relatively fixed in every pass you make, due to the performance being identical on each pass.
Normally, a player would play differently each pass, responding to these subtle interactions with an amp, on the fly, as part of the performance. This absence of pick-up interaction is only an issue with really good players who can work with intent with the subtleties involved, so, quite rightly, not everybody cares about this aspect.
Distortion processes that can add harmonics can be useful not only to gain harmonic density but also to give modulation effects something to work with.
If your sound happens to be a plain sine wave, you won’t get much joy from flangers and phasers and the like because the sine wave contains no harmonics – it’s simply a fundamental tone. Adding in a little distortion in the form of additional harmonics from an exciter, for instance, can improve this situation dramatically.
For many users, it is unimportant whether an amp simulation actually sounds like a specific real amp or even like any guitar amp at all. This is of the utmost concern to guitarists trying to carry lighter equipment to a gig, obviously. In the home studio, it doesn’t matter all that much, for the most part.
If it sounds good in the mix, it is good.
Real-world guitar amp and speaker combinations have been hard to model successfully until the last five years or so. There are challenging aspects of physics to account for, one of which is the presence of many non-linearities in the behaviour being simulated, meaning dynamic changes occur in the sound as the input level fluctuates. This really complicated things for a while, but today there are some amazingly realistic simulations. They still can’t quite beat a decent real amp in a sensible space with a dynamic or ribbon microphone, due to the mathematical complexities of the real world physics.
Most presets in amp simulations will automatically offer up a specific speaker cabinet emulation that goes with the amp well, but you can change to other cabinets if you wish. The SM57 small-diaphragm dynamic microphone is pretty ubiquitous in amp emulations as the virtual microphone in front of your virtual speaker (yet another emulation provided within the amp emulation GUI (graphical user Interface). There will be a virtual ribbon mic or two in most of the emulations, and usually a virtual large-diaphragm condenser mic as well. You may get a choice of positions for these virtual mics as well, which gives you quite a bit more flexibility with tone and room sound balances.
Running synth parts through these emulations, or, even better, through real guitar pedals and a real amp, miked up in a wooden-floored room, will make those synth parts, particularly your synth lead riffs, take on many of the characteristics we associate with lead guitars.
Some of the most modern amp emulations will allow you to operate in a stereo mode, where you can split the input signal into two or more parallel signal chains, which can be very cool. You can run two separate chains as separate L and R outputs, or you can run parallel signal chains that mix together at the output. There are great options here for taking a mono guitar signal and widening it into a stereo sound with a lot of motion and interest. If you duplicate the track without the amp emulation, you can leave the original panned in the middle at 12 o’clock, at, say, 10dB or so quieter than the wide stereo versions returning from the duplicate track(s) with the amp plug-ins inserted across them.
VINYL DEFECTS EMULATION, WAVE SHAPERS AND BIT CRUSHERS
Wave-shapers and bit-crushers (also called bit-reduction plug-ins) are the other main class of distortion processors that show up in DAW plug-in form.
Wave shaping is a means of adding new harmonics to a sound, as I mentioned in regard to providing mod effects with a little traction in the form of added grit in an otherwise bland sine wave.
It may seem counter-intuitive, but bit reduction can actually generate new harmonics in the signal. It won’t always do this, but it can in certain circumstances, which depend on the input signal’s characteristics.
There are lots of high-frequency overtones that appear in many bit-crusher processing results, due to the phenomenon of aliasing described in my sampling and synthesis blogposts earlier in this series.
The truncation of the bit depth of a signal by a bit-reduction plug-in can easily generate new high frequency content.
A variation on the theme is the modeling of the various defects of vinyl records, such as surface noise, hiss, warp, rumble, scratches and other charmingly quaint benefits of used vinyl.
The atmospheric vibe acquired by sampling crackly old records can be simulated in loops you have recorded yourself, playing the drums for yourself, for example. This is a perfect use for a product like the excellent originator, iZotope Vinyl, which totally rocks.
TAPE SATURATION EFFECTS
Saturation effects are perhaps the most subtle form of distortion available, and soft clipping the most popular goal. The gentle rounding off of the transients due to tape saturation is often referred to as “off-tape compression”.
Edgy, raw distortion effects are all very well, but what about smooth, pleasant, creamy distortion? It’s one of those songs that cries out for a soulful Santana solo rather than a blistering Alice In Chains rage-fest, if you will.
For smooth and sexy distortions of the subtle, lightly compressed-sounding kind, you are probably going to be very happy if you load up a virtual tape machine plug-in. These babies are fantastic at adding analog girth and vibe in a gentle yet clearly audible way.
There are several excellent virtual tape machines out there nowadays, and Slate VTM is an excellent example of the genre. It sounds fabulous, although there are only a handful of controls to adjust, mostly toggle switches, so you more or less take what it offers with fairly subtle differences between possible settings.
There are also excellent offerings for the UAD-2 platform, where you will find models of the Studer A800 1/2″ stereo tape recorder and the Ampex ATR-102 Master Recorder. These latter two recorders are perhaps the most highly regarded stereo master tape recorders in the analog studio world. Both these are more adjustable than the Slate VTM, and also sound great. personally, I tend to use the VTM or the Ampex ATR-102 most often, although the Studer A800 model is certainly awesome too and has a certain analog je ne sais quoi.
The first tape emulation out there was actually a hardware emulation, a plug-in in a rack format if you will.
It’s called the EL FATSO. The FATS of FATSO stands for Full Analog Tape Simulation) and it’s sold in 19″ rack format. It’s made by Empirical Labs (or just plain EL) who make some incredibly good products.
My favourite EL product in particular is the Distressor, perhaps the most versatile and all-round wonderful compressor in the world of 19″ rack format hardware compressors, especially with the so-called “British” modification (a popular option with customers).
I’ve had two “British” Distressors for over a decade and use them all the time in tracking and mixing. These are not compressors you would use in mastering applications, to my mind, but they are magnificent workhorses in all other applications.
Their FATSO virtual tape machine has been around for a decade or more now, and I still haven’t had the heart to sell mine, even though I use all the high-quality tape emulation plug-ins at times as well. I use those plug-ins all the time in mixing, where they really do offer up some analog-sounding magic.
I often use virtual tape machine emulations in mastering applications, and my clients love them as much as I do. Considering the cost of actual analog 2″ tape reels is about $100 for a single reel, and it only takes about 35 minutes or so to run out of tape given typical operation, you can see why plug-ins can very quickly save you money when compared to running even bargain-priced analog tape machines.
The plug-in is always perfectly aligned (if you don’t fool with it’s alignment options!) unlike the real tape machine which has to be aligned in a laborious process every morning. I would spend about half an hour every day on “lining up” the 2″ tape machine (using 100Hz, 1kHz and 10kHz test tones, and making tiny trim pot adjustments of various kinds for all 24 tracks) when I was working in large studios back in the Pleistocene era. I’m afraid I can’t really say I miss lining up tape machines…
So another wonderful yet largely unmentioned advantage of the plug-ins is that they will save you half an hour and the tape costs each and every day, as compared to running actual 2″ tape machines!
There really isn’t a lot to say about tape emulation except that it really adds something special. There are very good sonic reasons that folks were resistant to digital for a while in the early days – tape is flattering to probably 90% of audio signals. Only pristine, biting, digital synths and the most brutal of drums really benefit from not having softened transients.
I strongly recommend you try the demos of the UAD plug-ins if you have the UAD-2 PCI-e computer card installed in your DAW. If you don’t have a UAD-2 card of any type, then you should head straight over to Steven Slate Audio and grab a demo of the Slate VTM.
Another great aspect to virtual tape machines is that it’s fun to watch the animation of the tape reels turning and the tape going past the heads. The glowing VU meter is also extremely cool. This stuff makes recording even more fun!
Before taking on the somewhat related topic of transient designer plug-ins in a moment, I’ll close the tape emulation plug-in topic with a picture of the UAD-2 Ampex ATR-102 Master Recorder. Drool… I love using this one too, and can happily recommend it to you as great value if you do have a UAD-2 card.
Check system requirements for your intended purchases, as always! These things get rather expensive to collect, and you do want to be sure you only get products you will be able to use. Reading plug-in reviews in audio recording magazines and then downloading free demos is a reasonably reliable way to figure out where to allocate your dollars. I hope my blog helps too!
Transient enhancement plug-ins are another class of effects, pioneered by SPL in a 19″ rack-mount product called, appropriately enough, the SPL Transient Designer.
The SPL Transient Designer is now available as a plug-in, and there are quite a few others such as Stillwell Audio’s Transient Monster and still others from Voxengo and Flux. Waves offer the excellent TransX.
In the days of purely analog recording, transients did not survive entirely intact, but were instead rounded off somewhat due to the nature of magnetic tape. Rounded transients are a symptom caused by so-called “off-tape compression”. This flattered a great many sounds and affected where in a typical drum fader’s range you would end up while mixing a song, since the drums have excellent transients present at the onset of their (ADSR) envelope, the attack phase of the sound.
A transient is what we call an instantaneous peak signal. It’s the initial spike of level at the top of a sound like a snare drum right as it begins sounding, and before it decays back down in amplitude, as it inevitably will a moment later. A transient can occur in considerably less than a millisecond.
A lot of devices, particularly certain types of compressor, will have a Look-ahead feature that defeats any latency by reacting slightly before the transient appears. A few milliseconds of Lookahead time is plenty. This feature is also available in a lot of mastering limiters, where smooth results from peak limiting processes are absolutely essential.
You usually get an Attack and a Sustain control, and a Threshold control for threshold-dependent transient shaping (e.g. Logic’s Envelope Shaper).
With drums, you basically think of the sound as an attack transient followed by a fuller-sounding body phase, a sustain phase. Using the Transient Designer and similar plug-ins, you can deal with each of these two parts essentially independently, shaping the sound to suit you. It can be short and clicky or full of body and ringing longer, and many points in between. It’s actually quite surprising how useful these things are in the studio for a myriad of quick envelope shaping tasks. This is a sound design tool.
Check them out! They add bite or sustain to vocals, basses, keyboards and guitars too!
AUTO-TUNERS, PITCH SHIFTERS AND TIME-STRETCHERS
The Auto-Tuner category is dominated by two rival plug-ins, each with their own special signature features and useful in differing applications. You have your Auto-Tune+Time and you have your Melodyne.
We’ve all heard Auto-Tune’s nasal tonality and hard pitch correction effects.
You can actually be very subtle and transparent with both Auto-Tune and it’s only serious rival at the moment, Celemony’s Melodyne.
There are also lots of timestretch options out there if you want to change the length/tempo of a piece of music without changing it’s pitch/key. These have been around since the start of the 1990’s, and took 8 hours or more to process a typical length song in those days!
Using automation in your DAW, you can tweak the tuning and timing of your audio to your heart’s content, and you can do it very transparently, for the most part, or you can be glaringly obvious, using it as a deliberate effect for the cool attitude of it.
All I can say here is that music is no fun when it’s perfectly in tune and tempo on all sounds at all times. Imperfections are what make us human. Relatively subtle imperfections tend to be pleasing to the ear in moderation and I cannot recommend them highly enough.
Some of us remember “if you can’t do it live at a gig, don’t do it in the studio” as a line of (preposterous) reasoning often spouted in the “drum machine programming versus real drummers” era of the early 1980’s. This silly kind of ethical dogma has been repurposed to serve the folks who think that correcting time or tuning is the work of the devil. It’s just one more tool in the toolbox. You don’t like it, so don’t use it. Leave the rest of us who like the option to our choices. I rarely use it, but the public do expect close to perfect tuning so if you have pitching issues with your singer or yourself, it may prove really helpful in getting your recordings onto a more even playing field.
Mastering guru Bob Katz has invented a processor called K-Stereo Ambience Recovery, which is now available as an emulation on the UAD-2 platform.
This makes it possible to do a limited amount of ambience recovery, something that has been virtually impossible to do until Bob’s excellent invention arrived on the scene.
Tomorrow, I’ll blog on microphones themselves. I’ll save mic placement techniques for the following posts, but tomorrow it’s the guided tour of mic types.
Thanks for reading to the end of this rather long post! Have fun with those effects!