The most common questions we get re: gear here at TGF relate to amplifiers, and which one a given person should buy. Here's the cold hard fact:
we can't tell you what amplifier to buy. There are too many variables for us to do that. We might be able to get into the ballpark, but YOU have to actually play the amp for yourself and decide if you want it.
What we CAN do, however, is help educate you on the topic of amplifiers, so you can make the most informed decision possible. To that end, here is the TGF AMP FAQ.
ContentsTypes of Amplifiers
Tube amplifiers
Tube amplifiers, sometimes also called "Valve amplifiers", use vacuum tubes as components for the audio amplification, just like the old radios and television sets of the 1930s-70s.
Who uses them: Every guitarist I know of that can afford one that suits him. The only famous player I know of who used (past tense) a Solid state amp, rather than an all-tube amplifier, was Dimebag Darrell.
Why people use them: Tube amplifiers tend to be louder than their wattage rating implies. They also tend to have more presence, you "feel" the sound more. They also have a reputation for being warmer and more organic sounding, e.g., less "harsh" or "sharp" than solid state amplifiers.
How much they cost: Tube amplifiers range in quality and cost from $120 USD to as much as $5000 USD or more.
Who makes them:Marshall, Fender, Vox, Mesa-Boogie, Peavey, Bogner, VHT, Epiphone, Titan, and many more.
For more information: Wikipedia - Valve AmplifiersWikipedia - Guitar AmplifiersWikipedia - the Tube Sound (an article dealing solely with the unique characteristics of sound produced by tube amplifiers)
(Back To Top)Solid State Amplifiers
Solid state amplifiers do the same job as a tube amplifier, but instead of using vacuum tubes to amplify the sound, transistors and other "solid state" components are used. Many solid state amplifiers are also "modeling" amplifiers, in that they possess small DSPs and other on-board computer components that are used to simulate the sound of more famous tube-based amplifiers.
Who uses them: They are most often used by beginning guitarists, though some notably famous guitarists (Dimebag Darrell, for example) used solid state amplifiers.
Why they use them: Many people use solid state amplifiers (especially ones with digital modeling) because they cannot afford to get a more expensive, dedicated tube amplifier. With a tube amplifier, you tend to get one tone at which the amplifier excels; with solid state modeling amps, the user is given a wider variety of tones to choose from, even if none of them are particularly exceptional. Many people also use modeling amplifiers because their harsh distortion and clipping characteristics are often confused with "extra harmonics" by beginning high-gain metal and rock players. They are also less maintenance than a tube amplifier; you don't have to change tubes, for example. It has also been argued that solid state amplifiers, without using the delicate glass tubes, are less fragile and stand up better to heavy road usage than tube amplifiers. Further, many players claim that Solid State amps (such as the Roland JC120) provide better CLEAN tones than any Tube amplifier available, while most everyone agrees that solid state amplifiers generally do not provide overdriven or distorted tones as good as tube amplifiers.
How much they cost: Solid state amplifiers can run anywhere from $10 in a pawn shop to as much as $500 or more from retail.
Who makes them: Marshall, Fender, Vox, Peavey, Epiphone, and many more. Most "major" amp brands that make tube amplifiers also make solid state models.
For more information: Wikipedia - Guitar Amplifiers(Back To Top)Master Volume vs Non-Master Volume
There are two broad sub-categories of amps, that being those amplifiers with and without a Master Volume.
What does a master volume do? There are two major stages of a guitar amp, a pre-amplifier and a power amplifier. The pre-amp brings the low level instrument signal up to a workable volume where it can be modified by tone controls or other amplifier controls. The power amp then takes that line level signal and amplifies it to the output wattage necessary to drive the speakers at the desired volume. The volume control sits between the preamp and the poweramp, and limits the amount of signal the power amp receives. A volume knob, in "master volume knob" configuration, is combined with a preamp "gain" knob that determines the amount of signal the preamp receives from the instrument. The result is that you are able to achieve higher distortion levels at lower output volumes.
Master volume amps is also a term used to refer to amps which have two "channels" of preamp (a low gain and a high gain input channel, commonly) which each have their own independent volume controls, with a master volume controlling the overall output level of the amplifier.
What is a non-master volume amp? The non-master volume (or "NMV") amplifiers don't have the gain knob, so the preamp is always running at full volume; it does not have the gain control. It is also used to refer to amplifiers with multiple preamp channels which do not have a master volume or the ability to switch channels independently; rather, in these amplifiers, there is usually a "blending" control to determine how much of each channel is present in the final signal, or you can plug into the low/high gain input individually to select a channel to use without blending.
Why do I care? Because the two types of amplifiers produce wildly different sounds and are useful for different things. Non-master volume amps are appreciated by people who prefer simplicity in their amplifiers, yet these amplifiers can still be tuned to be incredibly dynamic pieces of equipment. They tend to be a more direct, raw type of sound when used in a gain configuration. Master volume amps, however, can be setup to have a completely clean sound on one channel of the preamp, and a very dirty sound on the other; and the two can be selected between individually, which some people prefer. In the case of master volume amps that are not 2-channel, the user appreciates the ability to achieve higher distortion at lower volumes; however many people will point out that this low volume distortion does not sound as good as high volume distortion, as the power amp and speakers are not being driven accordingly.
With a non-master volume/single channel amp, how do I go from clean to crunch? With your guitar's volume knob. Using your guitar's volume knob will reduce the amount of input signal to the preamp, resulting in less driven signal. Turning your guitar's volume back up gives the preamp more signal to drive and distort. With a NMV amp, the trend is to set the volume where you want the distortion to be with your guitar at 10, and then roll your guitar's volume back for clean tone, and roll it up to get the distortion. The pickup selector also changes the amount of signal going to the preamp.
Yes, those controls on your guitar DO CHANGE THINGS, and a NMV amp will really help you learn what they're for.
What are some examples of each type? The Marshall Superlead ("Plexi") and JTM45, and the Epiphone Valve Jr are good examples of non-master-volume amplifiers. Many amplifiers designed before the 1980s were made in this configuration. Master volume/independent channel amplifiers include the Marshall JCM800/900 and the JVM series, Peavey 5150, Mesa-Boogie Dual Rectifier, and just about every amplifier made past 1990.
(Back To Top)Output Watts and Speakers
("How LOUD is it?!")
There are two things that determine the volume of an amplifier: its output wattage rating, and the speakers you're running it into.
Output Watts: The wattage rating on an amplifier describes the amount of output power it is capable of sending to a loudspeaker. Essentially, without getting too technical, it means "this is how much horsepower I have". Watts, however, do NOT necessarily equal decibels; so more watts does not necessarily mean a huge decibel increase. For example, a 100 watt amplifier is only 3 dB louder than a 50 watt amplifier - which is just a little more than the threshold of "sound change" that the human ear can pick up. The main function of higher output wattage is to driver larger, and more, speakers into breakup range.
Speakers: The type of speaker in your amp, believe it or not, is what will control how loud you can get. A 5 watt amp through a wonderfully designed speaker will sound louder and more present than a 50 watt amp through a bad speaker. There are two things that make a speaker a "good" speaker: the speaker's efficiency, and its dynamic range. About.com has a good section on this, so I'll lift some copy from them:
http://stereos.about.com/od/stereoscience/a/amppower.htmSpeaker EfficiencySpeaker efficiency, also known as speaker sensitivity, is a measure of the speaker's output, measured in decibels, with a specified amount of amplifier power. For example, speaker efficiency is often measured with a microphone (connected to a sound level meter) placed one meter from the speaker . One watt of power is delivered to the speaker and the level meter measures the volume in decibels. The output level results in a measure of efficiency. Speakers range in efficiency or sensitivity from about 85dB (very inefficient) up to 105dB (very efficient). As a comparison, a speaker with 85 dB efficiency rating will take twice the amplifier power to reach to same volume as a speaker with 88 dB efficiency. Similarly, a speaker with a 88 dB efficiency rating will require ten times more power than a speaker with a 98 dB efficiency rating to play at the same level. If you're starting with a 100 watt/channel receiver, you would need 1000 watts (!) of power output to double the perceived volume level.
Dynamic RangeMusic is dynamic in nature. It is constantly changing in volume level and frequency. The best way to understand music's dynamic nature is to listen to live acoustic (un-amplified) music. An orchestra, for example, has a wide range of volume levels, from very quiet passages, to loud crescendos and some in-between quiet and loud. The range in volume level is known as dynamic range, the difference between the softest and loudest passages. When the same music is reproduced through an audio system, the system should reproduce the same range in loudness. When played back at an average volume level, the soft and medium passages in the music would require minimal power. If the receiver had 100 watts of power per channel, the soft and medium passages would require roughly 10-15 watts of power. However, the crescendos in the music would require more significantly more power for short periods of time, perhaps as much as 80 watts. A cymbal crash is another good example. Although it is a short term event, the cymbal crash demands lots of power for a short period of time. The ability of the receiver to deliver bursts of power for a short time is important for accurate sound reproduction. Although the receiver may only use a small portion of its maximum output most of the time, it must have the 'headroom' to deliver large amounts of power for short periods of time.
So there you have it - volume is actually more dependent on good speakers, than it is on your output rating. If the dynamic range on the speakers is crap, or if the efficiency sucks, you might be pushing your 50 watt amp to the limit, and only getting the volume of a 5 or 10 watt amp! And that same 5 or 10 watt amp, given a decent speaker, might sound very close to your 50 watt amp in loudness. So let that be a lesson -
do your research on the speakers that are in your amplifier before you buy. You want high dynamic range, and you want high efficiency ratings. Walk away from anything less.
Size and Amount of Speakers: So now that we know that buying good speakers is more important than a high output rating, we need to understand the phenomena of large speaker cabinets, as well as the size of the speakers in them.
Small speakers produce the same sound differently than large speakers; they have a smaller cone, and thus will vibrate a smaller amount of air when their cone is vibrated during amplification. This can often result in a constrained, thin sort of sound, or a muddy sound with no definition - there's no "breathing room" for the tone. Also, even though the speaker may have a good efficiency rating and dynamic range, a smaller speaker will seem quieter than a larger one because of the fact it's pushing less air as it makes sound; and therefore you must be in a more narrow range to hear the full volume of the speaker.
This is why big 4x12 speaker cabinets were invented. In the big arena rock situations - think of playing Butokan or Woodstock - it was difficult for artists to get their amplifiers, even at big 100 watt volumes, to the back of the audience. So they started using cabinets with 4 12" speakers in them; each speaker is larger, so it moves more air. And there are 4 of them, in a square configuration - so a 4x12 is pushing a LOT of sound. Even if the output wattage is low, a 2x12 or a 4x12 will make your amp seem much louder as it will help the sound carry further, and direct it over a wider area.
Band situations ("Beating the Drummer"): The main reason people care about output wattage is "keeping up with a drummer". In a band situation, the tendency is for everyone to keep turning their volume up so they can hear themselves over everyone else, especially the drummer, until everyone is (usually) louder than they need to be. Getting the guitarists & bassist to stop fighting about who needs to be loudest is an issue unto itself, but the drums are the sticking point. Acoustic drum kits naturally fall into the 100-110 dB range. Firstly if you want to keep up with a drummer, you need to pick a speaker which has enough efficiency to handle that range of volume; you need to be at least as loud as the drums to be heard. If you play in a light genre and your drummer can play with brushes, then you can do it with about 5-10 watts of Tube amplifier, or 15-20 watts of Solid State. If you play in rock or metal, and the drummer can't back off, and he really digs in, you'll need about 50 watts to break past the drummer in the mix. Anything beyond 50 isn't NECESSARY unless your drummer is absolutely insane (think Meshuggah).
So what speakers should I buy? When you buy a combo amp, or a cabinet for your head, make sure you're getting high efficiency, high dynamic range speakers. If you are afraid of your amp being too quiet, then instead of immediately going to a higher output wattage, try getting a bigger cabinet with GOOD speakers. More good speakers = more perceived volume (and a better chance of keeping up with your drummer!) The other important thing to realize is that different speakers have VERY different tonal characteristics! For an excellent demo of the exact same guitar tone put through many different kinds of well-respected speakers, check out this link (thanks Q!):
http://www.watfordvalves.com/soundfactory.asp(Back To Top)High Gain vs Medium Gain vs Low Gain
The amount of distortion, or gain, that an amplifier can produce will get it either a "high gain", "medium gain" or a "low gain" reputation. The usage of high gain vs low gain is mostly determined by the genre of music that you play. The table below can help you decide if you need a low/medium/high gain amp, as long as one remembers that every genre will always have a few artists who play something outside of the norm.
| GENRE | EXAMPLE ARTIST | GAIN TYPE |
| Heavy Metal | early Black Sabbath | Medium Gain |
| Modern Metal | Megadeth, Metallica, etc | High Gain |
| Classic Rock | Aerosmith, Led Zeppelin | Medium Gain |
| Blues | BB King, Eric Clapton | Low Gain |
| Country | Brad Paisley, Chet Atkins | Low Gain |
| Funk | Red Hot Chili Peppers, Bootsie | Medium Gain |
Gain Characteristics of Different Tubes in Tube Amplifiers
One thing about tube amplifiers is that the individual tubes used in the amp can make a huge difference in the sound. There are various different types of tubes that can be swapped into both the pre-amp and power-amp of most amplifiers, and they all possess varying gain statistics.
Gain FactorAll tubes possess a "gain factor", which rates how much they amplify - or add gain to - the input signal. This term is important for later.
Pre-Amp TubesThe 12AX7 is by far the most common preamp tube used in tube amplifiers today; in fact, it is used in ALL of the tube amplifiers listed on this page. However "12AX7" in common parlance can be a confusingly generic term; there are many, many different tubes that can be interchanged for the 12AX7, resulting in a wildly different array of tones. Also, many common tubes have different trade names, and are ACTUALLY the same tube, just with a different name. Consider the following table, which lists the gain factor and other names for common preamp tubes:
| Tube Name | Gain Factor | Other Common Names |
| 12AX7 | 100 | ECC83, 7025, ECC803, E83CC, 6681 |
| 5751 | 70 | None known |
| 12AT7 | 60 | ECC81, 6201, 6679 |
| 12AY7 | 45 - 50 | 6072 |
| 12AV7 | 40 | 5965 |
| 12AU7 | 19 | ECC82, 5963, 5814, 6189 |
As long as the tube socket has the same pinout and voltage, you can TECHNICALLY substitute any other tube with the same ratings, into the socket. Consider the following table, showing which preamp tubes are interchangable:
| 12AX7 | 5751 | 12AT7 | 12AY7 | 12AV7 | 12AU7 |
| 12AX7 | X | X | X | X | | |
| 5751 | X | X | X | X | | |
| 12AT7 | | X | X | X | | |
| 12AY7 | | X | X | X | X | |
| 12AV7 | | | | X | X | X |
| 12AU7 | | | | | X | X |
By substituting a lower gain factor tube into a socket meant for a higher gain factor tube, you can reduce the amount of breakup, and increase the clean range of the amplifier - at the expense of some volume. If, for example, you had a 12AX7 based preamp which begins to overdrive around 12 o'clock on the volume knob, and you want to get more clean range out of the amp - say you don't want it to start overdriving until about 2 or 3 o'clock - you could substitute a 12AY7 into the preamp socket. Now your amp would sound clean until about 3 o'clock on the volume knob - however, it would be quieter.
How does it work? Because the lower gain-factor tube provides less signal at the output. In the example, the original 12AX7 has a gain factor of 100, while the 12AY7 has a gain factor of between 45 and 50 - a gain drop of approximately 50%. This means you get 50% more of your volume knob that is "clean". However it also means that the amp loses a nearly proportional amount of volume, since there is 50% less signal at the output.
However you should note that this really doesn't work the opposite way - you shouldn't try to substitute a higher gain factor tube into a low gain factor tube's socket. The rest of the power amp circuit most likely isn't prepared for the additional signal that will be coming from the new tube. For example, putting a 12AX7 into a 12AY7 designed preamp will most likely kill your preamp, rendering it useless until repair occurs.
Power Amp TubesFIXME: Get some technical info on 5881, EL84, EL34, 6L6, etc, so I can do a proper description of them and how they might change the volume/gain of your amp.
(Back To Top)Rectifiers: What the Heck Are They?
Anyone who's spent very long playing guitar will have heard of the (now legendary) "Mesa Boogie Dual Rectifier", or the "Triple Rectifier". Or they'll have heard someone "Man I wish I could get that RECTIFIER tone!". But most of you will be left wondering - what the heck is a rectifier?
Simply put, a Rectifier is an electronic device that is used to convert AC (Alternating Current) power to DC (Direct Current). In a guitar amplifier, the power amplifier's output transformer (which makes the circuit match the impedance of the speaker) produces Alternating Current, but the speakers run in Direct Current. So, after the guitar's signal has been amplified to the desired output range, and the impedance has been matched to the speaker, the signal goes through the rectifier to convert it to DC to feed the speakers. (Technically speaking, the rectifier is PART of the power amp.)
So - what does this tell us? ... That's right - it tells us that
ALL tube amplifiers have rectifiers. Solid state amps generally don't, since they generally operate in DC all the way through the amp. But ALL tube amps have a rectifier. And that's true; if we look through the famous tube amplifiers in the later section of this document, we'll see rectifier tubes listed for almost all of them, and the ones that don't have a rectifier tube listed, use a solid state rectifier.
What's a solid state rectifier vs a tube rectifier? There are two basic types of rectifiers used in guitar amplifiers these days; the Tube rectifier, and the Silicon Diode rectifier (Solid State). The differences between the two are not of a whole lot of technical interest to the casual reader, just be aware that there are two different kinds, and (as usual) each one gives your amplifier a slightly different sound.
So wait a minute - if all tube amplifiers have a rectifier, then what's the big frickin deal about the "Mesa Dual Rectifier"? Ah! Notice the
Dual in the name. The big deal w/ the Mesa amps is that they actually have TWO different rectifiers in the back of the amp, selectable by a switch that you change without modifying your amp in any way. The amps feature both tube, and silicon diode, rectifiers - allowing you to select which you want to color your tone.
The reason Mesa's Dual and Triple Rectifiers are famous is less because of their rectifiers, and more because of their preamp and poweramp circuits. The rectifiers, and the name, are little more than an accidental coincidence to their fame. The common perception was that the number of rectifiers equalled the number of channels, which wasn't true. But the naming convention was so popular that it stuck; for example, while the Triple rectifier may have 3 channels, it still only has 2 rectifiers.
(Back To Top)Class A vs Class AB Tube Amps
"Class A" and "Class AB" are terms you'll hear alot when looking at tube guitar amplifiers. But what does it mean?
You gotta know your science Okay, quick science lesson. Most tubes used in tube amplifiers have 4 essential parts; a grid, a plate, a cathode, and a heater. The way they work is that the heater will heat (duh!) the cathode, which forms a cloud of negatively charged electrons. The plate, which is positively charged, will attract the electrons. (See? Pay attention in school, kids.) The grid is where the audio signal comes in, and it will generally control the speed and volume at which the electrons flow from the grid to the plate.
The voltage at the grid is low, and the voltage at the plate (which is drawing current from the power supply) is higher. This means that a small sound input at the grid and then applied to the plate will be LARGER on the plate - hence amplification. Cool!
Get to the pointClass A In class A designs, the amplification circuit is always "on" and at full power. It also uses a positive charge on the grid. Class A amplifies both halves of the waveform at once (the part above and below 0). Because the circuit is always "on", it is ready to amplify your signal at all times; this can mean a more dynamic response to your touch, as it doesn't have to spend milliseconds powering itself back up like an AB does. When setup in a push-pull design, the amplifier will tend to emphasize high-order harmonics, which some guitarists will prefer. However, there is not alot of headroom, and the tubes won't last as long.
Class AB In class AB designs, the amplification circuit has what they call "bias" - essentially there are two small circuits operating in tandem, and each one is only handling half the circuit at any given time. The "bias" is a negative charge which keeps both of these circuits alive, but at a low power level, when there's not actively any signal coming in. Class AB amplifiers are all push-pull by design, whereas class A may not be. Class AB designs are commonly credited with having better bass response, more headroom, better (e.g. more) distortion/overdrive, and longer tube life. However, it is widely agreed that Class AB is less responsive to dynamic touch than a class A amplifier, because of the fact that the circuit is "asleep" when voltage goes low.
WHAT DOES THAT MEAN?! Vox has, as far as I know, always been a Class A amplifier company. Marshall and Fender, on the other hand, produce largely AB designs. Some companies (such as Peavey) have become famous for producing variable sweep controls that move somewhere between A and AB. Other companies have produced amplifiers which have multiple modes (B-52 for example) wherein you can select either Class A or Class AB operation.
(
B-52 deserves special mention here because its Class selection switch is part of its "tri-mode rectification" technology - which wraps up the Class selection in with its selectable Tube or Diode rectification; thus one control is changing TWO characteristics of the amplifier which are not necessarily related. This can be confusing when the word "rectifier" is thrown into the mix, and must be explained. Many notable "rectifier" amps, such as the Mesa Boogie Dual Rectifier, have selectable rectification modes, but will always be hardwired as Class A or Class AB. It is important to understand that amplifier Class has little to do with the type of Rectifier in the amplifier.)
FIXME: I DON'T KNOW WHAT 'CLASS' (A/AB/B) SOLID STATE AMPS ARE. ARE THEY VARIABLE?For more info:
(Back To Top)Effects Loops
Guitar players tend to use alot of "stompboxes" to achieve various effects in their guitar playing. Some of these get hooked to the amplifier's input, being used to drive or modify the preamp signal. Others - such as choruses, reverb, delay, etc - need to be placed AFTER the preamp, so the preamp distortion does not happen over the effect. To achieve this, some amps include an "effects loop", which allows you to place effects after the preamp and before the poweramp.
(Back To Top)Famous Tube Amplifiers
Did you read everything above? ... REALLY?! ... Go read it again, i don't believe you.
Okay, now that you've done that, here's some famous amps along with their characteristics. These are the "guideposts" - every other amplifier is compared to these amps, so consider this when choosing an amp.
Fender Bassman
The fender bassman is pretty much the earliest electric guitar amp that anybody will commonly talk about. The Fender bassman was originally designed for bass players, but because it was actually a pretty crappy bass amp, it caught on with guitarists. It's famous for having a pretty nice, thick guitar tone, with plenty of bottom end. It's always been very popular with classic rock, blues, and some country guitarists. The fender bassman is a
non-master volume amp, having both "bright" (higher tone/gain) and "low" (normal) instrument inputs, and having individual "bright" and "low" volume knobs to create the blending effect described earlier. The amp has been made in countless versions by Fender, and was the design basis for our next amp ...
Video Example: http://www.youtube.com/watch?v=kICb4GcYMhAManufacturer: Fender
Type: Class AB, Low Gain, Non-Master Volume Tube Amplifier
Effects Loop: No
Output: Usually 50 watts
Tubes: Three 12AX7 tubes in the preamp, 2 6L6 tubes in the power amp, 5AR4 Rectifier tube
Speakers: Originals used Jensen P10R speakers in a 4x10 configuration, later models used Eminence speakers
Retail Price: ~$1500 USD
Famous Users of This Amplifier: Mike Campbell (Tom Petty & The Heartbreakers), Kurt Cobain (Nirvana), John Fogerty (Creedence Clearwater Revival), Josh Home (Queens of the Stone Age), Bryan Setzer (The Stray Cats), David Gilmour (Pink Floyd)
(Back To Top)Marshall JTM45
The Marshall JTM45 was a blatant copy of the Fender Bassman, simply made with British components; this resulted in a brighter sound, and crunchier distortion. The JTM45, like its fender Bassman counterpart, is a Non-Master volume tube amplifier. The JTM45, however, was originally built as a 30 watt output, and later had 45 and 50 watt versions released. Just like the bassman, the JTM45 is extremely popular in blues and some rock genres, and while having a less renowned clean tone, is still quite nice when clean. However the Marshall is known for having a slightly less "jangly" tone than the Fender, as Fenders tend to be more round and smooth, while Marshall's amps tend to overdrive and breakup more easily with their brighter sound.
Video Example: http://www.youtube.com/watch?v=x-fZNroRP0I <--
FIXME: SOMEONE FIND ME A BETTER JTM45 VIDEO!
Manufacturer: Marshall
Type: Class AB, Low-Medium Gain, Non-Master Volume Tube Amplifier
Effects Loop: No
Output: Originally 30 watts, 45 and 50 watt versions also made
Speakers: The original combo unit used Celestion Greenback speakers in a 2x12" configuration
Tubes: 3 ECC83 tubes in the preamp, 2 5881 tubes in the power amp, GZ34 tube in the Rectifier
Retail Price: ~$1600 USD
Famous Users of This Amplifier: Eric Clapton, Billy Gibbons (ZZ Top), Jimmy Page (Led Zeppelin), Angus Young (AC/DC)
(Back To Top)Fender Twin
This refers to both the generic "Tweed Twin" and the equally famous "Narrow Panel Twin", which is the one referred to in the video. The Twin was introduced at the same time as the Fender Stratocaster, and was its sales counterpart. The Twin was an instant success with rock, country, and blues guitarists because of its now absolutely famous clean tone, as well as its mild, smooth overdrive. The original Twin was, like the Bassman, a NMV circuit with bright and low inputs and blend knobs for each. Later reissues (such as the Blackface designs you will find in stores today) use 2 independent, footswitchable channels from one input. The twin is one of those amps that almost every guitarist will be able to pick out in a band's mix, and is widely regarded as one of the finest amps ever made.
Video Example: http://www.youtube.com/watch?v=xfLU2W0NTl4Manufacturer: Fender
Type: Class AB, Low Gain, Non-Master Volume Tube Amplifier, later versions are 2-channel Master Volume Tube Amplifiers
Effects Loop: No
Output: Originally 40 watts, many other wattages (up to 100) have been released over time
Speakers: The original Fender Narrow Panel Twin used 2 12" Jensen Alnico V Concert Series speakers, and one smaller tweeter whose manufacture I'm not sure of
Tubes: 3 12AX7 tubes in the preamp, 2 6L6 tubes in the power amp, dual 5U4 tubes in the rectifier
Retail Price: Between ~$1500 and ~$3000 USD
Famous Users of This Amplifier: David Gilmour (Pink Floyd), Eric Clapton, Curt Kobain, John Fogerty (Credence Clearwater Revival), Eddie Van Halen (Van Halen), Billy Gibbons (ZZ Top), Stevie Ray Vaughan, Dweezil Zappa
(Back To Top)Marshall Superlead ("Plexi")
The Marshall Superlead was introduced in 1959 as a 100 watt amplifier designed for Pete Townshend of The Who, who demanded an amplifier louder and grittier than anything currently produced. It is renowned as an amplifier with plenty of gain - sitting somewhere between Medium gain and High gain - and also having wonderful sparkly, dynamic cleans when cleaned up. This amp is widely regarded as the best amplifier to have for rock and roll, and even many metal guitarists use Plexi heads. It earned the name "Plexi" when the amplifier was adopted by Jimi Hendrix, whose versions had plexiglass front plates.
Video Example: http://www.youtube.com/watch?v=fR3Os80p0u4 (this video is of the 50 watt version, identical in features to its 100 watt cousin)
Manufacturer: Marshall
Type: Class AB, Medium-High Gain, Non-Master Volume Tube Amplifier
Effects Loop: Yes
Output: 100 and 50 watt versions
Speakers: Most commonly paired with Celestion Vintage 30s (12") or Celestion Greenback 12" speakers, usually in a 4x12 or 2x12 cabinet
Tubes: 3 ECC83 tubes in the preamp, 4 EL84s in the power amp
Retail Price: ~$2500 USD
Famous Users of This Amp: Joe Bonamassa, Dave Mustaine (Megadeth), Slash (Guns 'n Roses), Eddie Van Halen (Van Halen), Pete Townshend (The Who), Angus Young (AC/DC)
(Back To Top)Fender Hot Rod (Deluxe)
The Fender Hot Rod is a very popular amp from Fender that takes the Narrow Panel Twin design and pushes it to hotter overdrive characteristics, while still retaining the trademark Fender crystal clear tone. It is widely used for its large variety of tones, from clean to medium gain, and with the proper application of pedals it does a light high-gain fairly well. It is also widely liked for its low cost versus the rest of the Fender tube amp lineup, as well as its compact design (carrying only one 12" speaker) to make it easier to handle when traveling and gigging alot. However, due to the fact that the rectifier is solid state - even though it is correctly referred to as an "all tube" amp for its tube-based preamp and poweramp sections - some people look down on it for the inclusion of solid state components.
Video Example: Manufacturer: Fender
Type: Class AB, Low-Medium-LowHigh Gain, 2-channel Master Volume Tube Amplifier
Output: 40 watts
Speakers: One 12" Eminence Legend 125 50 watt speaker
Tubes: 3 12AX7 tubes in the preamp, 2 6L6 tubes in the power amp
Retail Price: ~$700 USD
Famous Users of This Amp: None known, but surely many are in rehearsal rooms of many big names
(Back To Top)Marshall JCM800
The Marshall JCM800 followed up on the success of Marshall's Plexi/Superlead design. It was adopted by heavy metal and hard rock guitarists in the 1980s as soon as it came out because of the additional amount of gain this amp could produce, as well as the fact that it was the first amplifier of the period to introduce the Master Volume control. The JCM800 was the amplifier responsible for ushering in the era of modern high-gain amplifiers, which powers the heavy metal of today.
Video Example: Manufacturer: Marshall
Type: Class AB, High Gain, Single Channel Master Volume Tube Amplifier
Effects Loop: Yes
Output: 100 watts, 50 watt version also released
Speakers: Most commonly used with Celestion Greenback or Celestion Vintage 30 speakers, in 2x12" or 4x12" configurations
Tubes: 3 ECC83 tubes in the preamp, 4 EL34s in the power amp
Retail Price: ~$2200 USD
Famous Users of This Amp: Kerry King (Slayer), Slash (Guns 'n Roses, Velvet Revolver), almost every rocker in the 1980s-mid 1990s
(Back To Top)Mesa Boogie Rectifier
The Mesa-Boogie Rectifier amplifier came on the scene at about the time of the Marshall JCM amplifiers, and were their direct competitors in the high-gain market. Mesa had higher gain, and better cleans (according to some) than their Marshall coutnerpart at the time. Based on the original Mesa Boogie Solo Rectifier, the Dual and Triple Rectifier feature selectable tube or diode rectifiers. The Triple Rectifier is the modern standard for ultra high-gain, three channel amplifiers. These amps are monsters on stage, and for those who enjoy the Rectifier sound - widely regarded as being fatter and more present, by those who enjoy it, compared to the Marshall sound - Marshall has not yet been able to produce anything that competes with it, and Mesa's main competition comes from other high-gain custom amp companies. This amp is widely used by heavy rock and thrash/heavy/speed/death/black metal groups.
Video Example: Manufacturer: Mesa Boogie
Type: Class AB, Very High Gain, Two or Three Channel Master Volume Tube Amplifier
Effects Loop: Yes
Output: 100 watts, other wattages available
Speakers: Many configurations used with head units, but the combo "Roadster" units shipped with Celestion Vintage 30 speakers in a 2x12 configuration
Tubes: 5 12AX7 tubes in the preamp, 4 6L6 tubes in the power amp, and 2 5U4 tubes in both the dual and triple rectifier
Retail Price: ~$2000 USD (head + cabinet)
Famous Users of This Amp: "Head" & "Munky" of Korn, Kirk Hammett & James Hetfield of Metallica, Jerry Mcpherson (Faith Hill), Pat Simmons (Doobie Brothers), Jerry Cantrell (Alice in Chains)
(Back To Top)Vox AC30
The Vox AC30 was introduced in the 60s, and was an instant hit with many rock pioneers (the Beatles being some of the most famous). It is a medium gain amp that has come out in many widely varied versions, and I don't really know enough about it to write this paragraph. Vox officianados have attributed the Vox's popularity to its "great clarity, very sweet, distinctive high-end sound. It has very little tube sag (resulting in hard clipping rather than soft clipping), and low-medium gain." (thanks Apopholis)
Video Example: http://www.youtube.com/watch?v=5oGwHJlDD78Manufacturer: Vox
Type: Class AB*, Low-Medium Gain, Single Channel Non-Master Volume Tube Amplifier (Other versions have been made w/ master volume and multiple channels)
Effects Loop: Yes
Output: 30 Watts
Speakers: Originally Goodmans Audiom 60's 15 Watt Speakers, later Celestion G12 alnico speakers, always in a 2x12" configuration.
Tubes: 3 12AX7 preamp tubes, 4 EL84 power amp tubes, 1 GZ34 rectfier tube
Retail Price: From ~$1000 USD to ~$2000 USD
Famous Users of This Amp: Bryan May of "Queen", Rory Gallagher, "The Edge" of U2, Jeff Beck, Jimmy Page (Led Zeppelin), Ritchie Blackmore (Deep Purple & Rainbow), the Beatles
* This amp is commonly referred to as being Class A: however, it is not *truly* a Class A design. It has a very hot bias, and is very similar to a class A design in terms of response; however, technically speaking it is NOT a Class A design. See this link for a thorough dissection of the Vox AC30 circuit for an explanation. (Back To Top)Epiphone Valve Jr
The Epiphone Valve Jr is a single-channel, non-master-volume amp (it has a single volume knob and no gain, no tone stack) which, while not carrying the output wattage of the more famous amplifiers (its output is 5 watts), caught on because of its good raw tone, simple "throwback" controls, and its famous suitability for modification by hobbyists. Epiphone Valve Jrs have a tone that has been described as "Voxy", especially at higher volumes when it begins to distort. Mods exist to make it sound more like a Marshall, or a Fender, as well as mods to add tone controls, a gain knob, bright switches, etc. It is also incredibly popular because it allows people who want a tube amplifier, but can't afford the higher end models, to have one anyway. Most people will leave it stock, or modify the internals for a more Marshall-y sound, while everyone agrees that the amp is very good when used with pedals.
Video Example:Manufacturer: Epiphone
Type: Class A, Low-Medium Gain, Single Channel Non-Master Volume Tube Amplifier
Effects Loop: No
Output: 5 Watts
Speakers: The extension cabinet has a 1x12" Eminence Lady Luck speaker rated for 70 watts; the combo version has a 1x8" Eminence speaker of unknown model
Tubes: One 12AX7 preamp tube, one EL84 power amp tube
Retail Price: ~$120 USD
Famous Users of This Amp: No famous users known, but the amp is highly regarded by all who come into contact with it.
(Back To Top)Famous Solid State Amplifiers
Roland JC-120
The Roland JC120 (short for "120 Watt Jazz Chorus") is a 2-channel Solid State amplifier that has a reputation for the absolute best clean tone of any guitar amplifier, ever. The Roland JC120 is one of the few amps that stands in distinction along with Fender's classic Tube Twin/Bassman amps as having a wonderful, uncolored clean tone. The Roland JC120 is sometimes used by Jazz players, as the name implies, but guitar players of every variety appreciate - and sometimes include in their rig - the JC120 for its clean tone.
Video Example: http://www.youtube.com/watch?v=5ZBv67KbFFQManufacturer: Roland
Type: Low Gain, 2-Channel, Master Volume Solid State Amplifier
Effects Loop: Yes
Output: 120 Watts
Speakers: JBL D120F in a 2x12" configuration
Retail Price: ~$1000 USD
Famous Users of This Amp: James Hetfield (Metallica) for clean tones, Robert Fripp and Adrian Belew (King Crimson), Robert Smith (The Cure), Paul Waggoner (Between the Buried and Me), Joe Strummer (The Clash)
(Back To Top)Lab Series L5
The Lab Series L5 was built by Norlin using both Gibson and Moog resources. Like the JC120, it is renowned for its clean tone, though the JC120 is a clear winner in clean tone. The Lab Series L5 is more famous amongst blues and light rock guitarists because, while it has wonderful cleans, it has a much better distortion than the JC120, being a good mild blues/blues-rock breakup. The amplifier is 2-channel, though it functions in a Master Volume blending mode, rather than channel-switching. The amp is no longer in production, but it is a favorite of none other than BB King, who prefers to use one at every gig. He has said that, when forced to play through a Fender Twin (the nearest approximation available to him), he is "very unsatisfied".
Video Example: http://www.youtube.com/watch?v=MqrLX0z8EUAManufacturer: Norlin
Type: Low Gain, Two Channel, Master Volume Solid State Amplifier
Effects Loop: Yes
Output: 100 Watts
Speakers: Unknown make and model - 2x12" speakers
Retail Price: ~$500 USD when you can find it, no longer manufactured
Famous Users of This Amp: BB King, Elliot Easton (The Cars), Ronnie Montrose, Ty Tabor (King's X)
(Back To Top)Tech-21 Trademark 60
The Tech-21 Trademark 60 is another 2-channel, Solid State amp renowned for its clarity and bluesy/overdriven punch. Tech-21, the company who makes the amplifier, is also famous for the SansAmp - which introduced the concept of amp modeling. The SansAmp tech is built into the Trademark 60, and can do a very good job of emulating Fender, Vox, Lab Series, and even some high gain sounds (possibly meant to model the JCM 800 or Mesa Rectifier); though, this amp really seems to shine in a light overdrive blues/blues-rock.
Video Example: http://www.youtube.com/watch?v=Rx4nJcUx_pgManufacturer: Tech-21
Type: Low-Medium Gain, Footswitchable 2-Channel, Master Volume Solid State Amplifier
Effects Loop: Yes
Output: 60 watts
Speakers: 1x12" and 2x12" models feature Celestion Seventy80 speakers, while the 4x12" features Eminence Model ET-2110-8 speakers
Retail Price: ~$600 USD to ~$900 USD
Famous Users of This Amp: Les Paul, Alex Scolnick, Sheryl Bailey
FIXME: Find more people who use this amp!
(Back To Top)Roland Cube Series
The Roland Cube series is a group of extremely popular low-cost, solid state modeling amplifiers. The name "Cube" is shorthand for a rather large list of offerings including:
- Micro Cube
- Street Cube
- Cube 15x
- Cube 20x
- Cube 30x
- Cube 60x
- Cube 80x
The Cube series comes in (quite literally) all shapes and sizes - from the Micro Cube, which can be stowed easily in a backpack while busking - to the Cube 80x which is much larger, has many more features, and easily keeps up with a drummer. The series has an almost infinite number of options depending on which model you choose, but all include multiple amplifier models - so one amplifier can do passable "copycat" modeling of classic Fender, Marshall, and Vox amplifiers. Since Roland is also the parent company of BOSS, many of the famous BOSS stompbox circuits (or passable copies of such) are built into the amplifier. This series of amplifier is widely recognised as the best low-cost option for a guitarist who wants an amplifier which can do many sounds, while not destroying their bank account, and still letting them get decent tone. It is also highly regarded since the Cube series' clean channel is based off of the famous JC120's clean channel.
Video Example: Manufacturer: Roland
Type: Low-Medium-High Gain, Single or 2-Channel (some come w/ a footswitch or accept MIDI footswitching), Master Volume, Modeling Solid State Amplifier
Effects Loop: No (
FIXME: There are a LOT of cube models... if I'm wrong here, someone please correct me)
Output: 5, 15, 20, 30, 60, 80, multiple other output wattages depending on model
Speakers: Unknown make and model, all come with a single 8", 10", or 12" speaker depending on model (15x, 20x, 30x, 60x)
FIXME: Does anybody know what the specific speakers are in these?!
Retail Price: ~$100 USD to ~$400 USD
Famous Users of This Amp: None that I'm aware of, mostly only used by amateurs, cover bands, or traveling musicians. However, still highly regarded.
(Back To Top)Parting Shots
Okay, so now you know pretty much everything you could know about how guitar amplifiers work, why they sound the way they do, and what some of the more famous models are good for. You know the difference between solid state and tube, and are capable of making an informed decision beyond just "solid state sucks, TUBES ARE TEH BROOTALZ!!!11!!!!"... So here's some parting shots on how you should do your amp shopping:
- KNOW WHAT YOU WANT. If you want to be a high gain player, and you want to sound just like Hammett or King, then be aware of that and don't waste your time looking at low-medium gain Fender Twins. If you want to be a low-medium gain player and you lust after the one of Clapton and BB King, then don't waste your time looking at high-gain monsters from Mesa or Marshall's JCM/JVM lines. If you want to do both, then be prepared to either buy 2 amps, break down and buy a solid state modeling amp, or to spend alot of money on a 3-channel amp with alot of versatility (and you WILL pay for such a beast).
- A Fool and His Money Are Soon Parted - SHOP SLOWLY. Don't buy the first thing that makes you go "Oooo"! Unless we're talking about a Lab Series L5, chances are they're still making it, and it'll be there when you come back after sleeping on it for a bit.
- Do your Homework Know as much as you possibly can about the amp before buying it. Are there any others that sound similar? Better? For the same price or less?
- SPEAKERS ARE EVERYTHING DON'T just buy something because it is really loud. LISTEN to the amp - if it doesn't sound good, then it's only gonna sound worse at the gig! Amps don't "break in" - what you hear on the shop floor is what you're buying. Make sure it has good speakers!
- It's YOUR tone - DON'T settle for second best! IT'S OKAY TO WAIT Until something better comes along! If you really want a new amp, but can't find something that is 100% what you want, DON'T SPEND THE MONEY. Don't go "man I really want XXX, but all I can afford right now is XYZ... guess I'll just get that." If you find that you can't contain the spending demon until your dream amp comes along, then drop just a little bit of money on a new stompbox, EQ, or something similar to tide you over.
- It's okay to be that guy with a hundred amps in his house - but it's not okay to be that guy with a hundred amps in his house, who hates all of them, because none of them sound good.
(Back To Top)Sources
This section lists webpages that I didn't specifically quote any of the text or images from, but which I used as a source of data in the construction of this article:
Music123 : Got most of the information on the tubes and speakers used in the amplifiers, as well as retail pricing on the amps, from this store's information
EBay : For amps that are discontinued, used ebay to try to get an idea of current price info
Tube Store Got some of my information on 12AX7 Tube compatibility and gain factor here
DIY Guitarist - Doublechecked my 12AX7 tube gain/compatability here
Wikipedia - Got much of my information here; I forget the exact names of the pages. Nothing was quoted verbatim, but if the description sounds overly scientific, it most likely was inspired by Wikipedia. Mostly I used Wikipedia for additional specifications or historical properties of various amplifiers, and the processes of various parts of an amplifier (such as descriptions of hard vs soft clipping in preamps)
Harmony Central Forums - I used a thread in this forum as a source of famous users of solid state amplifiers. I did as much independent fact-checking as I could, but most solid state amp users don't talk a whole lot about their gear, so there's some trust involved here.
Wikipedia - List of Fender Amplifier users Used this as an initial source for some of the users listed for Fender amps, and tried to confirm them by Googling.
Google - For everything else.
Marshall Amplifiers - Maker of Marshall amps, for a few Marshall specs
Fender Amplifiers - Maker of Fender amps, used for a few amp specs
Mesa Boogie - Maker of Mesa Boogie amps, used for amp specs
Vox Amplifiers - Maker of the AC30, used for speaker info
Epiphone - Maker of the Valve Jr, used for speaker specs
Roland USA - Guitar Amplifiers, didn't need to use their site, but here it is
Tech-21 - Maker of the Trademark 60, used for speaker information
Anyone I've missed - I'm sorry, I think I've attributed everybody here, but if I missed you, please accept my apologies. Please attach your grievance to the end of the thread, and we'll do our best to fix it up.
(Back To Top)
