Amplifiers come in all shapes and sizes, but here, we will be talking mainly about combination amps for guitar, bass, and other instruments, including vocals.
When it comes to playing music, there are two types of amps you really only need to be concerned with: combo amps, and heads and cabinets. A combo amp is just that, a combination of an amplifier and a cabinet, which is essentially just a speaker. Amplification in general is a complex topic, but here, all you need to know is that the main purpose of an amplifier is to take a low-volume audio signal and turn it into a louder audio signal.
Many musicians have small practice amps at home and have larger amps for performance use. Again, if the venue is very small, you might even be able to use your practice amp if you’re able to mic it into the venue’s PA system. For example, an acoustic-electric guitar set at a café.
For The Beginner
Anything between 10 to 30 watts is more than enough to practice at home and play small to medium gigs. The Crate FLEX 15w Combo Amp is an inexpensive amp that’s useful for many different sized playing environments. Light enough to carry with it’s handle, but the sound is far from light.
For simple home practice, the VOX Pathfinder 10 Guitar Amplispeaker is a 10-watt amp, loud enough for recording or home practice, and has that warm British sound. The old school exterior matches it’s timelessness.
For The Professional or More Advanced Player
You’ll want either a combo amp with a higher wattage, maybe in the 100w-200w range, or buy your cabinet and amp head separately. Buying them separately, instead of buying a combo, enables you to mix and match your set for ultimate personalization. But unless you plan on playing big clubs, a combo amp is really all you need, especially if you can get a mic up to it.
The Laney LX65R is a great combo amp for the seasoned musician, its 65 watts enough to play even mid-sized gigs. There’s an auxiliary input in the front, too, if you just feel like using it to play music from your iPod or CD player. A reverb knob lays on the front and it has two sets of EQ knobs, one set for clean and another set just for distortion.
The Fender Mustang III is a beast of an amp. Boasting 100 watts, no gig is too big for this monster combo. Fender’s Mustang series of amps come complete with USB connectivity and Fender Fuse software, which allows you to change your guitar sound right on your computer. And don’t forget those 37 different effects that you select on a digital readout on the top of the rig.
Open-Back vs Closed-Back Cabinets
Just like headphones, some cabinets come closed-back or open-back. Bass amps will be closed-back to give a more solid, focused sound, but most smaller combo non-bass guitar amps will be open-back, although really it’s more half-open than fully open. It fills the room better with sound since a bit of it emits from the back.
Clean & Distortion, Gain & Volume
Most amps will have a simple switch or button that will toggle between a clean sound and a distorted sound. With this, you’ll have multiple knobs to control the “overdrive,” as many amps list it as. You might want to keep it clean and use your own distortion pedal if you want more personalization, or perhaps you’ll use your whole own intricate pedalboard setup.
Amps will also have a knob labeled “gain” or “drive.” This is the input to the preamp, which slowly starts turning distorted the higher you go. Think of it as a gradient between clean and distortion. If the gain is at 10, and the volume as at 1, you can play extremely distorted while still being very quiet, a useful tool if maybe you’re at home and can’t play very loud, but still prefer your crunchy distortion as opposed to playing clean.
The “gain” or “drive”, however, has no change on the volume. There is a separate knob labeled “volume,” and this is the final strength of the outputted audio signal. Crank up the gain and the volume and then you get loud crunchy distortion. When the amp is set to clean, the gain knob’s influence is much less than when it is set to the distortion setting.
Bells & Whistles
Amps come with a variety of knobs and switches on the front (and sometimes the top) that effect the sound and that includes the clean or distortion switch. EQ knobs come on all amps, usually 3 in total, one each for the low-end, the mid-range, and the high-range frequencies.
For home practice, consider an amp with a headphone input, so you can play without sound omitting through the main speaker. A lot of amps also have external speaker outputs, so you can hook up your amp to an even bigger speaker system.
Some amps are even small enough to fit in the palm of your hand!
Consider the Marshall MS 2C Micro. While only 1 watt, it’s perfect to bring to the park, a backyard get-together, or in a hotel if you’re traveling, but still want to rock out.
The main distinction of an amp designed for a bass guitar is that it’s a closed-back design and the insides are built to suit better the lower frequencies a bass guitar produces. The Laney RB2 Richter is 30 watts and can tilt back as well as sit flat.
For other instruments like keyboards, vocals, or any other instrument meant to play clean and can plug in, a clean amp like the Fender Acoustasonic amp is a great choice, being that it’s designed for clean performance. It’s perfect for acoustic-electric guitars and other instruments where a clean sound is preferred over a distorted one.