Guitar Amplifiers – How Many Watts Are Enough?

If you’re an active guitar player, you’ve certainly noticed the continuing trend towards smaller, lower powered amplifiers. This has occurred for a number of reasons: Popularity of boutique clones of early amplifier designs, older players downsizing to focus on playing at home rather than performing, and the advent of very good affordable sound reinforcement systems.

Historically, the first guitar amplifiers were pretty small because the guitar was not necessarily the lead instrument of the band, and in many cases the band itself was not amplified. Plus the technology of the time – tubes – dictated smaller low power systems.

As rock music and the electric guitar became more popular, both the volume levels and the size of the venues increased. But true high quality “house” sound systems like today did not exist. So the guitar amplifier was not for “tone”, but was also the primary vehicle for what the audience heard. Amplifiers also did double or triple duty: Check out the input panel of many early amplifiers and you’ll see input jacks for multiple guitars and microphones. Adjusted for today’s dollars, pro gear back in the day was vastly more expensive than now, and sharing was a practical necessity.

So like the Space Race, the power race was on, and by the end of the 50’s the larger guitar amplifiers were pushing 50 watts or more. Fender’s introduction of the blackface amps in the early 60’s addressed the need for louder, cleaner sound. The blackface amps differed from their tweed predecessors in a number of ways, but features such as fixed bias design, higher plate voltages, and solid-state rectification had more to do with volume and headroom than tone. The largest amps topped out at 100 watts, which is really the practical limit of four 6L6 or EL-34 power tubes. This is pretty much true today for tube amps, and anything more than that gets very heavy and hot (bass players had it tough then). Today a bass player can get a 500-watt Class D solid-state amplifier that’s the size of a phone book.

But back then if you were going to play an arena, you needed stacks of amplifiers because they were doing a lot of the heavy lifting. Plus it’s kind a macho thing and looks really cool too. Today, you can play an arena with a 15-watt amplifier, and some performers do. While there is a certain visceral sensation to the sound of a 4×12, the need for a row of Marshall stacks is essentially visual. And unless you’re Yngwie Malmsteen, many of those cabs on stage aren’t even on.

So how much power do you actually need? Unless you require extremely high levels of clean volume without the assist of a PA, 50 watts is the most you’ll ever need. How much volume an amplifier produces is a function of its design: Fixed versus cathode bias, amount of negative feedback, plate voltage, rectifier type, etc. It’s hard to generalize, but a 15-watt amplifier with no negative feedback and a solid-state rectifier can be very loud and clean. My main amp head has (4) 6V6 tubes, solid state rectifier and a 20/40-watt switch. The only time it’s on 40 watts is when the band is playing outside.

If you are playing clubs and typically put the guitars through the PA, 15-30 watts will likely do it. While early amplifier designs were guided by power output, choosing an amplifier today is more about how you want it to sound, rather than how loud it will go. If you play mostly at home or jam with friends, 10-30 watts is where a lot of the amplifier market is targeted these days. Finding the right amount clean headroom – which is important if you use pedals – is an important selection criteria. If you regularly jam with a drummer, 30 watts is probably a better choice than 10. Five-watt amplifiers can be fun, if all you want is loose, old school grind. But with a humbucker-equipped guitar, there will be little in the way of decent clean volume.

Many modern amp designs have the ability to vary total amplifier output. Some do this by actually dropping out power tubes (4-to-2 for example) while others vary the amount of voltage to the power tubes or phase inverter. These features cut volume as well as headroom, allowing the ability to clip the power tubes at reasonable volumes. The Traynor Ironhorse amplifier has a fixed/cathode bias switch that changes the output of the amp from 37 to 17 watts, respectively. This not only affects total volume and headroom, but also the feel (I like the softer nature of cathode bias).

If you have a large amp that you don’t want to part with, there are of course power attenuators, which are available as an add-on accessory. These work by absorbing some of the energy that would normally go to your speakers. In effect, you can crank the amplifier but the attenuator “soaks up” some of the energy (volume). Attenuators work by placing some type of resistance/inductance network in the signal path to the speakers. Without getting technical, even the best ones mess with the feel of the amp, and how the guitar interacts with the amplifier. It’s hard to explain but it’s a disconnected feeling. They sound good on YouTube, but so does everything. My suggestion is to buy a smaller amplifier.

The trend towards lower stage volumes, and the affordability of good sound reinforcement and monitoring systems has been a boon to amateur and pro players alike. Using a guitar amp as the sole amplification source is very rare, and your band will actually sound better if you turn down and let the PA and the monitors do their job. And your band mates will appreciate it. Which brings us to the guitar player’s favorite lament of “I can’t hear myself.” Which is a topic we’ll address shortly.

 

Two neat EL34 guitar amplifiers from Traynor

If you crave the sound of the classic big British amplifiers, then you should check out amplifiers using the EL34 type power tube. The EL34 power tube was originally released by Mullard-Phillips in the 1950’s and in most common amplifier applications produces about 25 watts per tube. This is the power tube associated with the big British amps of the 60’s and 70’s produced by Marshall, Orange, Hiwatt and others.

The EL34 power tube has great harmonic detail, and a broad upper midrange that really fattens up the unwound strings of a guitar without making it sound muddy. Single note lines tend to have a lot of “meat” to them making amplifiers using these types of tubes sound both bright and thick at the same time. Traynor has two affordable amplifiers using the EL34 power tube, each with it’s own unique features.

Traynor Ironhorse – This Ironhorse is a “lunchbox” style of amplifier that uses (2) El34 power tubes and is switchable for either cathode or fixed bias. The fixed bias mode produces 40 watts, and is the tightest/brightest setting with the most available clean headroom. The cathode bias setting produces fewer than 20 watts and while still providing a good amount of clean headroom, has a little softer attack and a bit more “feel” to it. With a gain, master volume control and a three-way tone stack control it’s easy to dial in some natural crunch, or keep it clean and get your jollies with pedals. The Ironhorse is honest and tasty El-34 tone for great classic rock crunch in an affordable and lightweight package. It’s on the mark  for all sorts of live situations, and with the money you save on this amp you can go get yourself a nice set of new or NOS power tubes. It comes with a nice soft gig bag too.

Traynor YBA Mod 1 – In Traynor-speak, YBA means “Yorkville Bass Amplifier, which is what the 40-watt YBA was originally designed as. But the YBA found favor with guitar players too, and the Mod 1 version adds the ability to place the bright and normal channels in series or parallel, and adds an attenuator. In series the volume controls act like a master/gain control, while in parallel they function like normal/bright channels that you can blend just like a Tweed Fender. The attenuator can vary the ouptut power from .5 watts all the way up to 40 watts. At low wattage settings you can get all sorts of massive rock clang at very reasonable levels, while 20 watts is good for even the loudest of stage volumes. It’s hard to imagine even needing the 40 watt setting. Like the Ironhorse, the YBA has the complex crunch and texture that EL-34 tubes do best, and the added attenuation feature makes it good for practice and recording. Not quite as portable as the Ironhorse and pretty darn loud, but the attenuator can essentially size this amp from a large club down to a bedroom.

If you are looking to change up your sound, think about your amplifier too, and not just your guitar. With the EL84 dominating the small amplifier market, many players have never sampled the brawnier more harmonically rich tones of the EL34. So for less than a high quality solid body, you can get a taste of the tone that powered the British Invasion.

Pedal Amps – What’s a Pedal Amp?

Nearly every guitar player today uses some type of effect pedal, either for practice, recording or  playing live. Safe to say there is hardly anyone who does not own some type of effect pedal, making them both a great market for manufacturers, but also a real consideration when deciding what type of amplifier to use.

One of the frequent questions asked these days on the gear pages is what’s a good “Pedal Amp?” So what is a Pedal Amp? I would define a Pedal Amp as an amplifier that does not add extreme tonal coloration, and is able to handle high signal inputs without adding additional coloration or distortions. To some that does not sound like a particularly good amplifier, as for many old-school players the amplifier is an essential part of the sound equation. But for players that increasingly use various types of effects and digital modeling, the amplifier becomes more of an “amplification system” and less of a tone source.

Going back a few decades, the early amplifiers were instrumental to the developing sound of rock music. The happy accident of distortion, and then the use of lots of distortion as the essential rock guitar sound was not what the Founding Fathers intended. But as recording techniques, sound systems, and musical styles evolved, the concept of a pure unaffected guitar tone became increasingly rare. From the early days of cranking up small wattage amplifiers to get grindy tone, practically everyone today — well maybe not Neil Young — is using some type of effect to generate anything from mild to insane distortion. And while there are zillions of multi-channel amps out there, for flexibility’s sake pedals just allow much more room to mix and match tone.

So what makes a good Pedal Amp? In a word: Headroom. From a design standpoint, early amplifiers were notoriously short of headroom, both in the preamp and power sections. This of course gave them their warm creamy tone, but pump a high gain pedal into a Fender Tweed and the net result will be mushy distortion with very loose undefined low end. Practically speaking the pedal is creating distortion, and the higher input signal from the pedal is also distorting the preamp of the guitar amplifier. Distortion-on-distortion is not always desirable or musical.

Generally speaking, low powered cathode biased amplifiers (Tweeds, small Vox’s, lots of other low power EL-84 amplifiers) are not super candidates for pedals that have the capability of generating fairly high input levels. Even the relatively brawny 45 watt Fender Bassman won’t handle a lot of input signal without getting floppy. Hot input signals can come from distortion pedals or frequency modulation pedals (chorus, flangers) that tend to increase the signal level. Now boost pedals are made specifically to increase the signal, often for the purpose of overdriving the front end of an amplifier. But a boost pedal it typically only increasing the signal, and not adding its own distortion or other artifacts.

The boutique amp craze, with its plethora low power Tweed and Vox inspired designs (Dr. Z, Matchless, Badd Cat, Victoria etc) created some awesome sounding amplifiers that well-heeled baby boomers were craving. However they were not necessarily great at handling pedals, and even at 18 watts a Maz 18 is still damn loud. And this inspired the attenuator craze….and now everybody just buys pedals.

Fixed biased amplifiers — like Fender Blackface or similar designs — by virtue of their circuit topology have higher headroom and tolerate pedals better. Fender of course was trying to make louder and cleaner amplifiers to fill the larger venues that rock bands were playing. For that reason amplifiers that follow the higher powered Fender Blackface 6L6 tube lineage tend to be pretty good pedal amplifiers.

Once amplifier designers discovered master volume techniques and cascading gain (preamp distortion) techniques, amplifier designs became “stiffer” cleaner and louder. The general elimination of tube rectifiers in favor of diode rectifiers also increased headroom, and made the amplifiers sag less, and play cleaner under heavy loads. Distortion was now a design goal, not a by-product of marginal design or power handling capability. But to some, all these improvements — including dreaded solid state — took away some of the “organic” nature of the early amplifier sound.

Fast forward to the boutique amp craze and builders were putting all this “marginal” stuff back into amplifiers: Cathode bias, low power, and tube rectifiers. And at the opposite end of the spectrum some players are now using a totally digital preamp source — like an Axe Effect Fractal or Eleven Rack — and a powered full-range speaker system from JBL, QSC, or EV.

So back to the original topic: Good Pedal Amps tend to be more modern or higher powered designs that can tolerate strong signal inputs, and if they use a tube power amp section, have a solid state rectifier. If you are playing live or play at high volumes and want to use gain pedals, it’s advisable to avoid lower powered designs in the mold of a Tweed or Vox. Nothing against these amps — Robert Cray through a Matchless is a great sound — but it’s not a pedal sound. There are always exceptions to the rules of course, and some of the boutique designs using the EF-86 preamp tube (Dr Z. Z-28 for example) have quite of bit of clean headroom despite modest power outputs. It’s always dangerous to generalize.

Speaking of which, what about the Mesa Dual and Triple-Rec designs. Don’t they also violate the low power/tube rectifier rule? Yes, sort of. Up around 100 watts, tube rectifiers are pretty marginal AC-to-DC converters for creating the high voltage DC that power tubes need. By wiring two rectifiers in parallel, each rectifier is only carrying half the current, and therefore can share the load and maintain headroom (Fender did this on some 50’s amps for the same reason). A Triple-Rec adds one more rectifier for handling even higher powered designs. Mesa could have just used solid state diodes, but a Mesa Diode Roadking lacks marketing pizazz. Most Mesa — and modern metal — amplifiers are characterized by very “clean” clean channels and the distortion is produced by various combinations of tube and solid state wizardry.

Finally, here’s a personal example with the two amps I like to play the most: A Fender Reissue Bassman, and a Dr. Z Remedy head plugged into a Mojo Pine 4×10 cabinet with Jensen P10R/Eminence Blueframe speakers. Both are using virtually identical speaker arrangements, speakers, and cabinet materials. But the Bassman is an early cathode bias design with a tube rectifier, and the Remedy is a solid state rectifier design using four 6V6 tubes (not a “reissue” design but billed as having Marshall Plexi-style tone). They both have the same power output, about 40 watts. I love the Bassman tone, but in gigging situations using pedals for various levels of gain and effects, the amp loses definition, attack, and can get sloppy. Even on half power, the Remedy has better attack, low end firmness, and is overall tighter. Crunchy gain is crunchy gain. On full power the Remedy is really too clean for most situations except outdoor gigs. But both are 40 watt amps.

My general rule of thumb for any amplifier selection is to find the best clean tone that makes you happy and then go pedal shopping. If your favorite tone is clean to slightly crunchy, you may never need pedals and a smaller lowered powered “old school” amplifier may be the ticket. But if you are like most players, make sure the amplifier of your dreams has sufficiently stout headroom to serve as a suitable platform for whatever pedals you decide to use down the road.

For more information on platform and pedal options at Upfront Guitars:  www.upfrontguitars.com