Amplifiers have certainly come a long way. Actually, a lot of things have, if you check out the picture above. Notice how Son and Dad are playing a game the girls clearly can’t understand as they wash the dishes in the back, smiling at how much fun the boys are having. Try getting a picture like this past any modern marketing department now!

This battle, however, takes place not in a kitchen, but what surely should be a Very Big Room. Because, as Nick pointed out in his recent article, amps sound different when set to LOUD. This article will help to explain the difference between the traditional non-master volume amp, and the more modern (and more common) master volume tube amplifier.

In the beginning…

There were tubes. And it was good. Actually, I am not much of a tube snob, even though by age I qualify to be one. But ‘back in the day’ (as the kids say) there was only one kind of amp: the tube amp. In fact, any electronic device from radios to TVs used tubes, as solid state technology took awhile to gain traction. Early amps had a volume control, but no master volume. What does this mean? In short, you get a clean sound at bedroom volume levels. While playing with a band (when the amp is loud), the tubes can cut off some of the peaks and valleys of the signal, creating some distortion.

The musicians loved how the distortion thickened their sound, added sustain, and allowed them to shape the note with their fingers, pick and volume control. However, this newfangled sound was frowned upon by the designers of the amps:

“Why, their amps are distorting the electric guitar signal! This simply won’t do! Our amps are not powerful enough to compete with today’s Rocking and Rolling music!”

So they made bigger and bigger amps. Musicians turned those up. Eventually guitarists added boost pedals in front to hit the input of the amp with more signal, and get even more distortion. This was the sound of rock music until the mid-70s or so. Every classic guitar recording of this time used the non-master volume amps, and any distortion was the result of pre-boosting the signal before the amp, or just turning the sucka up loud. But the song remains the same: these early amps don’t naturally distort on their own, unless you turn them up loud. Really loud.

Why would I want an amp without distortion?

In a world where almost every amp has distortion built in, it is difficult to understand why so many guitarists still seek out old amps. While it is true that most of these amps remain clean up until they are painfully loud- easily heard above the drummer, the bassist and the whole PA, they remain popular for a few reasons.

They are a great candidate for those who get their primary distortion sound with pedals. The list of pedals that sound great with these amps is pretty large these days, but my favorite these days is the Dirty Deed.

Lower powered tube amps are not nearly as loud, and can be turned up without hearing damage and complaints from the neighbors. This allows the power tubes to distort the signal, and provide a round, squishy, touch sensitive distortion. In other words, the guitarist has the ultimate control over tone shaping with just the controls on the guitar and the fingers. Styles such as blues, country, jazz, and classic rock rely on this touch sensitivity, and are used to getting many sounds out of the guitar just by modifying the way they play. Distortion and timbre change with picking dynamics and these players rely on the tone and volume knobs of the guitars much more than other players.

Wow, that sounds cool! I want an old tube amp now!

Not so fast, Beethoven. While non-master volume amps might be fine for the styles listed above, their soft & squishy response make them difficult to use for more modern styles. Modern metal, punk & alternative rock rely on that super-tight preamp distortion with a low end you can feel from across the arena. Non-master volume amps won’t do that, and the low end in amps that feature 6v6 power amp tubes can sound quite flabby at higher volumes. This is great for playing open string chords, but not so good for power chord or detuned chug-fests.

Also, louder non-master volume amps have to be on the heavy side, as tubes, transformers and speakers designed to play at that volume for a long time need to be big.

The Modern Age: Master Volume Amps

The idea of achieving that gainy/sustainy sound at low volume levels is is an old one, and the person who brought that idea to the public in a big way was Randall Smith, the founder of Mesa/Boogie. Starting out by modifying those non-master volume Fenders for players like Santana, Randall added gain stages adding more and more sustain to the notes at a reasonable volume. Players like Santana loved this, and that idea of cascading gain from one preamp tube to another, before it hits the power tubes, was born.

Nowadays, most amps sold have a master volume. This allows a reasonably good facsimile of an amp on 11, while still not disturbing your older sister’s history homework. I say ‘reasonably good’ because it isn’t exact, and a distorted sound at a low volume sounds different to our ears- and makes us play differently.

Master volume amps compress the signal more, and sound much tighter (especially in the lows) than non-master volume amps. After Santana, people could buy a big amp, stick it on 1, and rock out. The volume is there for the big show, but the master volume limits the overall loudness at home. Master volume amps derive much of their sound from preamp tube distortion, which adds to the tight low end and overall compressed nature of the sound.

I play Da Metalz, so I need Da Gainz

Heavier styles, like progressive metal and punk can really benefit from that tighter sound of master volume amps. The sound of a high-output pickup, like the Dimebucker or Invader slamming the preamp tubes with an already-hot signal is the classic recipe for modern heavy music. Here, we are not so concerned with touch-sensitivity, and the added compression keeps the rhythms thumpin’ while the solos keep a-pumpin’. It isn’t as important to get those higher voltage power amp tubes to distort, although at higher volumes, this adds to the sound as well. Check out Jay Hale’s excellent guide to amps on the heavy side of the scale.

Where I sit…

Personally, it doesn’t matter to me. I get much of my gain from pedals, and don’t use much of it anyway- just enough to enhance sustain but no more. If I can’t play a minor 9th chord without it sounding like mush, chances are I won’t like the amp. One of my amps is a Mesa Blue Angel. No master volume here, 6v6s & EL84s, and I get my distortion from a combination of turning it up (18 watt setting), and an overdrive pedal (some sort of TS variant). Touch sensitivity for days.

The other amp I use is a Tech 21 Trademark 60, a solid state analog modeling amp. I use mostly the clean channel, although the overdrive rocks too. Both channels have a master volume. Again, if I like the sound of the amp, it is easy to dial in, and light enough for me to carry with one hand, then I am sold. I don’t play as much heavy music these days anyway, so it works for me.

What kind of amp do you prefer? What is the best sounding amp you have ever heard?

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