Understand and being able to differentiate between the many types of guitar amps is one of those things that accomplished musicians can do effortlessly.
Broadly speaking, there are four types suitable for an electric guitar:
- tube/valve
- solid state/transistor
- modeling
- hybrid
Each uses different technology (well, variations on the same technology) to produce tone and are a combination of combo, head, or half stack/full stack.
In this article, we’ll walk you through each one and the pros and cons of each.
Tube/Valve
Tube (or ‘valve’ in England) amps use vacuum tubes/valves to make sound.
They were the first type of guitar amp to exist and most of the great rock and blues tracks we know and love were recorded using one – hence why they’ll always be favored by guitarists.
The one characteristic they are known for, above everything else, is warmth.
The other thing you’ll want to be aware of is a term known as headroom. As the level of the signal that enters the tubes increases, so does the level of distortion in the sound output. So they give you natural overdrive.
This means they have a particular volume and gain at which everything will begin to sound muddier. Metal, blues, and rock music were built on this.
Advantages
- Gorgeous warm tone
- Straight-forward to use (usually relatively few knobs)
- The real deal for rock guitar. If you want to sound like any of the greats (e.g. Jimmy Page, Jimi Hendrix, George Harrison, Jeff Beck, Eric Clapton, etc.) you’ll need one.
- The best tube amps last a lifetime and improve with age
Disadvantages
- Need to be driven (i.e. cranked) to get an overdriven tone, unless you use an attenuator (in other words, they don’t produce good tones at low volumes)
- Not particularly versatile. You’re relatively limited in the tones you can get.
- Because of their boutique status, they tend to be pricey
- Vacuum tubes are made of glass and will break or burn out over time and need replacing, so these amps need more maintenance than solid state amps
- These types of electric guitar amps are heavy, so if you struggle with a bad back, think twice. The 30-watt VOX AC30, for example weighs 70lbs (32kg) compared to the Roland Chorus JC-120 (120-watt) that weighs in at 62lbs (28kg).
- They are noisy, so expect some hiss (which all adds to the tone, in my opinion, but if you like a super clean sound these aren’t for you).
Solid State/Transistor
Solid state or ‘transistor’ amps are generally more dependable since they utilize transistors in place of tubes. The signal never changes and has no possibility of overloading the amp, resulting in them being cheaper and easier to maintain, as the only real damage you’re likely to do is blow out the speaker if you insist on playing metal with all of the settings cranked up to the max.
The sound of these lacks a lot of the unique character found in tube amps, but they are still hugely popular and the preferred option for many guitarists such as Radiohead’s guitarist Jonny Greenwood who plays a Solid State Fender Eighty-Five, as well as John Fogerty and Andy Summers, among others.
They’re also great for modern jazz, where players often want a super clean tone. The Roland Chorus JC-120 is one of the favorites.
Advantages
- Much lighter in weight than a tube amp (see the comparison above between the Vox and the Roland)
- Much cheaper than tube amps
- Sparkly clean tones great for certain genres, such as jazz
- They require zero maintenance, as they don’t have vacuum tubes to burn out and replace
Disadvantages
- The tone tends to be too clean for rock guitar
- They won’t produce natural overdrive
- They’ve been overtaken by modeling amps (see below)
Modeling
An evolution of the solid state amp is known as the modeling amp, often called a ‘digital guitar amp’. These use computer circuitry to emulate (or ‘model’) the sound of some of the most famous and recognizable amps in the world. They’re lighter, more reliable – and if shop around, some modeling amps such as the Line 6 Spider V120 sound pretty good.
Let’s say you want to play some 1960’s Bluesbreaker era Clapton sounding guitar, press a button and you have the sound of a Marshall stack. Or the next minute you want to play some Mark Knopfler sounding stuff through a VOX AC30, or some Carlos Santana through a Mesa Boogie. Modeling amps have presets for all these sounds.
Sure, they don’t sound 100% like the real thing, but they’re often close enough. Many of the best practice amps are modeling amps.
Advantages
- Access to sometimes hundreds of different amp models, inbuilt effects, and presets.
- Lighter than both tube and even solid state amps
- Very affordable
Disadvantages
- As the tech improves, the older models quickly become obsolete so the shelf life of these is relatively short
Still not convinced they can accurately emulate the real thing? Try this challenge and see:
Hybrid
If you really can’t decide between valve and transistor, you could always choose a hybrid. As the name suggests, hybrid amps offer you (in theory at least) the warmth of a tube amp and the reliability of solid state amps.
They’re a great compromise. If can’t stand the idea of an electronically emulated tube sound, these pack real tubes (sometimes just one tube) as well as all the electronic stuff you’d expect to find in a solid state amp.
The downside? You can end up betwixt and between. In other words, a tube amp that sounds a bit naff, and a solid state that’s not a great sounding transistor amp. They’re also more expensive than modeling amps.
Advantages
- They use at least one real vacuum tube for an authentic tone
- Much more versatile than your typical tube amp, with a bigger range of tones and effects
Disadvantages
- Heavier than a modeling amp
- Pricey
Combo vs Head
Combo amps have everything you need built into one box (preamp, power amp, speakers) – including the controls for volume, gain, and EQ, any built-in effects like overdrive or reverb, inputs, and outputs for effects pedals, amplification circuitry and at least one or two speakers.
The combo amp is great for playing at home or small gigs which don’t need extreme levels of volume. Bigger venues will require more wattage, that’s where ‘head’ units come into play.
Unlike the combo variety, head amps don’t include speakers – the only thing they do is amplify your signal, meaning you can hook up as many speakers (called ‘speaker cabinets’ or ‘cabs’) as you like. This lets you use the same device to cover an entire range of venues, from smaller gigs up to the biggest arena. All you need to do is choose which speakers you’re going to connect it to.
Half Stack vs Full Stack
The term ‘half stack’ is used when a head amp is played through 4 x 12″ speakers, whereas the term ‘full stack’ is used when it powers a pair of 4 x 12″ speaker cabinets.
Summary
So there you have it, four types of guitar amps that each have their own pros and cons.
When deciding which is right for you, it’s helpful to think about what you plan to do with it.
Will you be gigging with it, or is it likely never to leave your home? If portability is key, don’t go with a tube amp.
Will you like the ability to jump from one amp voicing to another, or are you perfectly happy with one tone? If you like to jump around, don’t go with a tube amp.
Do you plan to record with it? Digital amps are far easier to record with than many tube amps. Therefore avoid tube amps.
Are you most bothered about the tone? Do you want to sound like the guitar greats? Then it HAS TO BE a tube amp, despite all the flaws I just mentioned 🙂
Good luck with choosing, and don’t obsess over your choice too much. Amps are pretty easy to shift, so you can always sell it on if you grow tired of it after a while. The most important thing to get playing, and not go into analysis paralysis over gear.
Good luck!
