PART II - Core effects for amplified acoustic performance
INTRODUCTION
When applied sparingly, effects in acoustic-electric performances can be used to subtly reshape the sound of an instrument or to thicken the tone of the pickups.
Part II of this series focuses on the effects most frequently found in an electroacoustic setting. These effects collectively serve as the backbone of an amplified acoustic tonal palette, with many becoming increasingly useful as a signal chain expands to include more intrusive effects. If you use an acoustic multi-effects pedal, every effect it provides is most likely covered here.
Part II is long, but bear with me; I promise not to waste your time. Part II is broken up into two sections: essential core effects and non-essential core effects.
SECTION A: ESSENTIALS - PREAMPS, EQUALIZATION, TUNERS, MUTE & BOOST SWITCHES, AND REVERB
Special note: Although I am considering each effect separately in this post, many items in the section are often combined into a single unit (preamp/DI box, acoustic amplifer, or PA system mixer).
A.1: Preamps
I'll begin by addressing the elephant in the room: preamps.
In short, just get it over with and buy a decent preamp. You'll thank me later when you start dabbling in other effects; even active ukulele pickups often don't generate enough signal for many effects pedals to work correctly, but the outputs and effects loop sends on preamps do. If your instrument is equipped with a passive pickup and you intend to use effects, you need a preamp/DI box. For a thorough explanation of why you should invest in a preamp for your passive pickups and how to choose the right preamp for your needs, see UUer Booli's website:
http://bd.entropyadept.com/faq.html.
Even if you use an active pickup, a preamp/DI box might be a wise investment. Many preamps and DI boxes provide myriad benefits to the effects-savvy 'ukulelist, including but not limited to:
- EQ controls for tone shaping
- Anti-feedback features like high-pass filters. notch filters (high-Q, narrow-band EQ cuts; see A.2: Equalizers) and phase reversal switches
- Noise control features like a mute. boost. and ground lift switches
- Effects loop for keeping your other pedals out of your signal chain when not in use
- Balanced XLR outputs for longer cable runs to a mixer or PA system
And that summarizes preamps: not exciting or glamorous, but imminently practical. That brings us to our next boring-but-oh-so-useful "effect"....
A.2: Equalization (EQ)
A feature common to many acoustic amplifiers and PA systems, EQ is not always located on the pedalboard itself. EQ allows the player to boost or cut different bandwidths (called bands) of the frequency spectrum to modify the timbre of the output signal. A dedicated equalizer is generally broken up into several roughly discrete bands, each with the following properties:
- Gain - the degree of cut or boost applied
- Center - the median frequency value in the band
- Quality factor (Q) - a ratio of the frequency to the bandwidth. A high Q means a sharper peak or valley will form within the response curve of the band whereas a low Q means the cut or boost in gain will be dispersed over a broader part of the band
Technically, most pedals can be thought of as EQ pedals, but I will limit this discussion to dedicated EQ pedals. Three types of dedicated EQ pedals are commonly available:
- Graphic - visually represents frequency response settings with a set of vertical sliders. Easy to use and affordable, but often voiced specifically for electric guitar
- Parametric - flexible, with highly editable bands and robust anti-feedback features. Present a steep learning curve and can be expensive
- Semiparametric - combines a 2- or 3-band EQ with a parametric mid-band. An effective compromise between the complexity of a fully parametric EQ and the ease-of-use of a graphic EQ
Many semiparametric and parametric EQs include anti-feedback features like phase reversal switches and notch filters.
A.3: Tuners
Put a tuner on your pedalboard; your audience demands it.
Tuners come in four main forms:
- Stroboscopic - compares an input signal to an internally generated pitch. Latches on almost immediately. Can be extremely accurate but expensive
- Microprocessor - processes a few cycles of a tone before latching on. Noticeably slower and slightly less accurate, but more affordable
- Otic organs (left or right) - extremely fast once trained, but prone to fatigue and is rendered dysfunctional by background noise
Many tuners come with additional features. Common features of tuners include:
- backlit needle or LCD or LED display
- buffered output, sometimes true bypass with a switch
- polyphonic tuning
- display brightness controls
- mute switch that turns off the output when the tuner is activated
- power jack out for powering another pedal when not in use
- Ménière's disease, vertigo, and tinnitus
One special factor to consider is the brightness of the readout display. Some are blindingly bright in the bedroom while other are too dim to use in direct sunlight.
With a bit of practice, you can learn to watch a pedal tuner's readout in your peripheral vision and pretend you are the master sommelier of intonation or a demigod born from the loins of Apollo and Euterpe.
A.4: Mute Switch
Does what you'd expect: turns the signal off when activated. This is surprisingly valuable when trying to control feedback or limit instrument handling noise.
Please note that many tuners and DI boxes feature a mute switch. If you don't already have a mute switch in your chain, you should consider adding one. They're listed here in the Essentials section for a reason (just make sure you find a quiet one unless you want to hear a pop every time you unmute).
A.5: Clean Boost Switch
Raises signal level. A boost switch can help your solos cut through the mix or give you a second gain stage to adjust to changes in audience size. Alternatively, you can use a clean boost to drive an overdrive pedal into a greater amount of distortion. Note that a "clean" boost will raise gain and almost always color your sound a bit. As before, boost switches are common on preamps and DI boxes.
Special note: preferences regarding boost are varied, and many alternatives to accomplish this effect exist. Some options include:
- Graphic equalizer - very clean option. cut the bass and highs, boost the other bands a bit, and you'll cut through the mix very effectively. Very unobtrusive
- Volume pedal - set your level at the amplifier for soloing, then back off the volume pedal until you're ready for a boost. This can prove especially helpful if you use dirt in your rhythm tone
- Overdrive/distortion/fuzz - set the level high to boost your signal and introduce a bit of grit and compression. A very popular method
- Compressor - set the compression/sustain low and the level high. This will sometimes limit your maximum volume but will minimize distortion while also adding a bit of your compressor's EQ
Second special note: a clean boost expects a high-impedance signal and generally won't work as intended if you plug a passive pickup straight into one. For this application of a clean boost, you will most likely need a preamp.
A.6: Reverb
In many cases, you can rely on the PA system or acoustic amplifier for a touch of reverb, but you can also put highly editable, dedicated digital reverbs at your feet.
Most reverb pedals feature several different algorithms for generating different types of reverb (usually based on analog analogues like plate reverb or spring reverb), with each algorithm category having its own unique flavor. Common algorithms include:
- Room - decay starts out simple but becomes complex. Especially useful for subtler touches or livening up an acoustically lackluster space
- Hall - nice wash of reverb with long tails; useful for soaring melodies or ambient harmonies
- Spring - classic electric and archtop guitar or organ reverb type. Extremely flexible and an evergreen option
- Plate - similar but not identical to room reverb, with greater complexity and more evenness across the decay
Many reverb pedals supplement these algorithms with additional features. Examples include:
- shimmer - pitch-shifted (generally augmented) decay tails
- predelay - varies the time between the attack and first reflection of the decay
