Like any other amplifier a guitar amplifier is usually designed specifically for guitar. It amplifies the sound from the guitar pickups and is considered just as important to the sound of the guitar as the guitar itself. They come in all types, sizes, and colors. Depending upon the sound you are looking for will determine what type of amp you should get. Guitar amps are meant to color the sound which is the exact opposite of what you want from a PA or stereo system. For instance a guitar amp won't sound very good at all when used for amplifying a vocal mic or keyboard. These amps are made with a limited frequency response not only from the amp but from the speakers used as well. They are made to color/change/modify the sound of the signal coming in. They of course amplify the sound to the level of volume for use with the musical situation. For the most part the guitar amps of today are actually amplified signal processors. It should be mentioned that speakers also have an effect on the sound of the amp. The size, manufacture, model, and type of speaker make a big difference in the sound. Speakers also distort and are meant to – in this case.

Types of Guitar Amps:

There are two basic types of amps those which use tubes or valves as they are called in Europe, and those which use transistors called solid state amps. Of the two most guitarists prefer the sound of tubes over that of transistor. At the same time the reliability of a transistor amp is much better.

Tube amps consist of just that, tubes. They have a round, fat, and more musical tone than solid state. They also produce more even harmonics which gives them their rich warm sound. Even when turned up until they distort the sound of a tube amp is still preferred by most guitarists even today. Some of the problem with them is they are usually heavier in weight and noisier than solid state. They are also more likely to fail especially if you just drop your amp on the floor, so you have to be more careful with them. You should let your amp warm up before trying to play anything through it. You’ll have to periodically change the tubes this will depend upon how often you play and the style of music.

Solid State amps are usually made of transistors or what is more commonly known as op amps (small scale integration). They can also be made of integrated chips which contain a number of op amps and other chips, capacitors, and resistors all on a single chip. The output section is transistor based as well. You can tell what the amp uses, tube or transistors, by looking at the back of the amp. If you see transistors then you probably only see a large heat sink which is usually a black or silver block of metal with cooling fins. The tube amps will obviously have tubes in the back but they might be a Hybrid Amp (Tube and Transistor). Some of the more popular tube amps are the Marshall JCM800, Fender Twin Reverb, and Vox AC30. Some solid state amps are the Roland JC120, Line 6 Spider, and the Fender FM212r.

Hybrids (Combo of Tube and Transistors):

Hybrid amps are a combination of tube and transistor. They usually have a tube preamp section and a solid state power amp section. This gives a similar effect to what an all tube amp would sound like. Other types of hybrid amps use a transistor preamp section with a tube power amp section. Some amps may only use a single 12AX7 preamp tube on one of the channels of the amp. Some Hybrid Amps include the Vox Valvetronix (tube pre, solid state power), and Marshall Valvestate amps.

DSP or Amp Modeling Amps:

These amps are digital emulations based upon the data of other amplifiers (tube, solid state, and hybrid). Each amp is recorded at various states of use: clean, bluesy, loud, and extremely loud where the recording is then analyzed to see how it behaves in the various states. A mathematical model is then created based upon this information and programmed into a Digital Signal Processor. A number of different parts of the guitar amplifier can be analyzed and linked together like you would link together a guitar to chorus pedal, to amp, to speakers, and finally to a microphone. This allows you to select a particular type of preamp, say a Marshall Plexi, and then run it through a 2 x 12 open back cabinet and finally through a shure 57 microphone. Some of these amps also include built in digital effects as well.

These amps usually use a transistor power amp stage with a DSP (Digital Signal Processing) preamp stage. It is actually a hybrid of Analog and Digital technologies. It consists of a guitar input (1/4 inch) which is feed into an Analog to Digital converter where the guitar signal is digitized. This resulting digital audio data is then sent to the DSP unit where the DSP is preprogrammed with a number of different emulations as well as various effect type of algorithms. Some of these algorithms include digital delay, digital reverb, digital distortion, and many other guitar related effects. These are the latest thing going mainly because this type of technology has lowered the price of guitar amps considerably. You can also find many guitar amp modeling preamps in the form of table top or rack mount boxes and even software you can run on your computer. Some Modeling amplifiers include: Many amps by Line 6, Native Instruments Guitar Rig, and Epiphone Triggerman.

History of the Guitar Amp:

As with the Electric Guitar the origins of the guitar amp aren’t really known. The first guitar amp was probably a hi-fi or pa amplifier. The transistor hadn’t yet been invented. Rickenbacker and Gibson started making guitar amps in the late 30’s. Gibson had a model that was meant to be sold with the ES-150 which was their first hollowbody electric. This was in 1937 where it appeared in the Gibson catalogue. Rickenbacker is known to have manufactured their first electric guitar in 1932 but there is no mention of an amplifier to go with it. When they and Gibson started manufacturing amps they were based on the current amps used in radio and hi-fi amps.

Fender got in to the act in the mid 40’s (1945) with the company was still called K&F Manufacturing. They were also very simple amps and didn’t have any controls (volume or tone). You used the guitar’s volume and tone controls. It wasn’t until after the aliens landed at Roswell J (1947) that Fender introduced their first amp. It still didn’t have any volume, and tone controls. It was the Model 26 which used a 6V6 and Jensen speakers. The transformer was actually mounted onto the speaker rather than inside the amp housing. The first guitar amp with a volume control was the Fender Champion 600. These amps where beginner’s amps (similar to the Champ Amp of today) and used a single 6V6 output tube. Also in 1947 Fender introduced the Dual Pro which had two channels and two volume controls (one for each channel) and a single tone control. These amps where used for the pedal and lap steel guitars as well as hollow and solid body electrics.

In the early 50’s Gibson introduced the Les Paul Amp which used the 6L6 output tubes. It was also of a similar designed to that of the Fender which was based upon the RCA tube application manual. The demand for louder amps came around this time as well. Fender responded with the Tweed Series of amps and most notably the Fender Bassman. These amps had more tone controls (treble, middle, and bass) as well as a Presence control and found the use of the now very popular 12AX7 and 12AY7 preamp tubes. These tubes allowed the amps to have more tone variation than any amp. With the Tweed amps you found one of the first uses of ‘Vibrato’ (modulating pitch changes) and ‘Tremolo’ (modulating volume changes). Each of these functions further advanced the sound of guitar amps.

Vox introduced the AC15 in 1956 which was the first amp to use a class ‘A’ design. The Fender and Gibson amps all where class ‘B’. The Vox amps even though only had 15 watts or so where loud and sounded great when turned up (distortion). They became the amp of choice for England guitarist mainly because Fender amps cost too much. The Beatles for instance used Vox Amps quite extensively. Some of the more important Vox amps are the AC30, AC50, as well as the AC100. The number was the amount of watts the amps put out. There was one great Vox amp called the Vox AC30TB. The TB meant Top Boost which it had because of the addition of an extra tube.

The 1960’s found the guitar amp in even more demand with the start of Rock-n-Roll. Fender introduced there famous BlackFaced amps. These amps were known for their great tone and reliability. These amps are the first Fenders where the controls of the amp are on the front panel instead of the top panel. The Fender Tweeds, Gibsons, and Vox amps all had their controls mounted on the top of the amps so the guitarist could clearly see the amp settings. This change to move the control knobs to the front of panel probably came from the amps being louder. With the amp being louder caused the guitarist to be located further away from the amp. This meant that they couldn’t see the controls if they were on top of the amp. So they got moved to the front. From what I can find out is the Fender VibroVerb was the first amp to have a spring reverb. Gibson had around the same time as this something called a Maestro EchoPlex. The EchoPlex was the first tape delay system that used a ¼ inch tape to record the guitar and then delay it and then play it back. This could be used to create a not so convincing reverb effect.

Here are three of the used amps I have in stock, I'm always buying and selling so if I dont have the amp you want now, I might later, just keep visiting. Click on the blue links for Musicians Friends pricing, then call me :^)

Fender 65 Deluxe Reverb Combo Amp:

The Fender ’65 Deluxe Reverb is a reissue and is one of the most popular amps for recording and studio work. It works well for all types of music from blues to rock and everything in-between. It is single channel all tube amp with 22 watts of power that drives a single 12 inch Jensen. This amp was originally designed many years ago and had evolved to such a point that the ’65 model was considered one of the best years for the amp. This is a Blackfaced Fender re-issue and comes with the famous spring reverb. Its main tube complement is 6V6’s for the power amp and 12AX7’s for the preamp.

It has two channels: Normal and Vibrato. The vibrato channel has and you guessed it vibrato as well as treble, bass and reverb. The normal channel has treble and bass controls. On earlier models the Deluxe amp the tremolo and preamp inputs where shared which allowed both input controls and tremolo to be used. Fender added two 7025 tubes around ’63 which gave each input channel ( Normal and Bright) their own preamp circuit. This reissue amp no longer shares the input preamp or tremolo and the tremolo circuit now operates exclusively on the Vibrato channel. The vibrato circuit is simply a ‘photo-resistor’ that oscillates the amplitude of the guitar input signal. It basically varies the amount of the signal is sent to ground.

The tubes in the amp consist of a 5AR4 Power Rectifier tube, two 6V6 power output tubes, four 12AX7 tubes and two 12AT7 tubes. The preamp sections use 12AX7 while the 12AT7’s are used for the reverb driver and the power tube inverters/drivers. There are two input jacks per channel: 1 and 2. Input 2 is less sensitive by 6dB and is used for pre-amplified guitars. The vibrato channel gives you more treble than the normal channel. As mentioned the two channels operate in independently of one and other.

The 12 inch speaker is a Jensen C-12k which has 8-ohms and 100 watts rating. As for the frequency response of the speaker you’ll notice a pronounce peak at around 2000 Hz which is great for a good sounding speaker. The cone is made of paper while the magnet is ferrite. This is the same type of speaker used in the original amp that was ‘designed for Fender’ by Jensen. The components used on this amp are the same or better than that found on the original. The only exception seems to be in the use of a printed circuit board over the original plastic panel. Some might say that this changes the sound but I really couldn’t notice. The transformers used have the same specifications as well.

For rock and dirty blues tones the amp sounds best when cranked up between 8 and 10. You can get more gain from a preamp pedal like an Ibanez tube screamer or some other preamp. Plugging the guitar into both channels will also give you more gain. You can use a ‘Y’ cable or preferably a one in and two out DI box. This way you can drive both input preamps. The amp doesn’t have a master volume! But it’s only 22 watts and a single 12 inch which can still get very loud.

Features:

• Vintage Tone of the original Deluxe Reverb
• All Tube Amp Design
• Same specs on electrical componets (resistors, caps, and transformers)
• Same cosmetics with Black Faced Front panel
• Single 12 inch CK-12 Jensen speaker
• 22 Watts of Power
• Two 6V6GT power tubes
• Great Tube Tone for all types of music

Fender Hot Rod Deluxe Blonde:

The Fender Hot Rod Deluxe is a three channel all tube 40 watt guitar amp for the professional guitarist. It was introduced in 1997 with a vintage amp look and design. These are revved up specs with touch sensitive dynamics and sound great for any style of music. The amp has a tweed vintage look but the amp covering is Tan Tolex (with oxblood grille cloth) which was introduced in the early 60's. Another Vintage quality is the vintage pointer (chicken head) control knobs are that located on the top of the amp instead of in the front. The knobs on top are how fender amps where made in the early years.

The amp itself uses two Groove Tube 6L6 output tubes which put out about 40 watts into a single 12 inch 8 ohm Fender Designed Eminence speaker. Most original tweed amps used Jensen speakers but this speaker is made to handle the 40 watt RMS output. There is an internal variable bias control for re-biasing the tubes if and when you need to replace them. The power supply is built using a solid state rectifier which seems to not have the coveted voltage sag when you really hit the strings and the amps turned up. The older fender amps, especially the tweeds used a tube rectifier which produced an effect that gives the guitar a compressed sound. This was really caused from the tube rectifier not being able to respond fast enough to the power required by the tubes themselves. The amp has a 1/4 inch external speaker jack on the back for connecting to another speaker cabinet. Try running it through a 4 x 12 cabinet for some serious volume.

The input section includes tow 1/4 inch input jacks which are connected to three channels labeled: Normal, Drive, and More Drive. The Drive and More Drive have Gain and master gain controls which you'd expect. The More Drive is actually a switch that adds more gain to the Drive channel so there isn't any other knobs or controls other than the switch. You can select between the channels using the included 2-button footswitch. As with all fender hot rod amps there are three 12AX7 input/preamp tubes used for the preamp, EQ, and reverb driver.

The knobs and controls on the top of the amp from left to right are: Normal/Bright switch, Volume Knob, More Drive Switch, Treble, Bass, Middle, Channel Select button, Master Gain Knob, Reverb Knob, and Presence Knob. The difference between the normal and drive channels is the drive channel adds the extra drive control for more gain and distortion. The Reverb and Presence controls work on all channels and are not switchable. The Reverb is a fender long spring reverb unit that is loosely mounted inside the bottom of the cabinet.

On the top control panel there's also a power amp input and a preamp output. The preamp output sounds best when plugged into another amp but is meant to be used as an effects loop. The preamp output goes to your effects and the effects output (return) is plugged into the 'Power Amp In' jack on the top panel.

Features:

• 40 watts of Tube Sound
• All Tube Design (Except for Solid State Rectifier)
• Three Channels (Normal, Drive, and More Drive)
• Bright switch in Normal channel
• Presence Control
• Master Volume Control
• Reverb Control
• Two Input Jacks (Wired in parallel)
• Two Groove Tube 6L6 power tubes
• Three 12AX7 Preamp tubes (EQ, Reverb Driver)
• Fender Spring Reverb
• Internal Variable Bias Control
• External Speaker Jack
• Two Button Footswitch for Channel Switching
• Nylon cover included
• 45 lbs.

Marshall JCM2000 DSL 100 Amp Head:

The Marshall JCM2000 DSL 100 is a 100 watt all tube head designed for the professional guitarist. It’s a cross between the JCM 800 and the 1959 SLP (Super Lead Plexi) or its like have two 1959SLP’s in one amp where each one has its own master volume. If you only need 50 watts then see DSL 50. The sound of the amp is from 1959SLP clean to ultra gain like that found on the JCM800 2203. DSL (Dual Super Lead) means it has two channels: Classic (normal) and Ultra which can get sound ranging from clean to high gain JCM800 style sound. Each of two footswitchable channels can operate in two different modes by pressing a switch located between its Volume and Gain controls. This mode switch is used to change the channel’s voicing and gain characteristics. For the Ultra Gain channel the first mode gives you a high gain JCM800 style tone while the second mode is even louder with a midrange boost for higher gain possibilities. The Classic Gain channel modes are Clean and Crunch. Clean allows you to go from Clean to a Plexi type of crunch while in Crunch mode you can go up to JCM800 2203 Grind sound.

The JCM2000 is an all tube amp with the exception of the solid-state rectifier. The power section uses (4) EL-34 power tubes which outputs up to 100 watts in to 16, 8, or 4 ohm cabinets. There are three speaker jacks on the back panel. On is for connecting to a 16 ohm cabinet only while the other two are wired in parallel. The two parallel jacks can be used to connect to a single 4 ohm cabinet, single 8 ohm cabinet, or two 8 ohm cabinets. 4 ohms is the lowest rating the amp can use so it won’t work with two 4 ohm cabinets for instance.

The four 12AX7 (ECC83) preamp tubes are for the two preamp channels, reverb driver, Tone Shift and Deep circuits, and effects loop. The ECC83’s and the power tubes are the sound of the amp. The Deep Switch is located on the front panel of the amp and gives your tone a tune bass resonance that increases the low-end of your sound without making it sound muddy or boomy (good low end). The Tone Shift is used to get a scooped out tone usually found in Metal. With the switch pushed in you can then turn the Middle tone control to remove a lot of the mids for a classic metal tone.

The controls on the front panel of the amp from left to right are: Deep switch, Presence, Treble, Middle, Bass, Tone Shift switch, Reverb Channel B, Reverb Channel A, Volume for Ultra channel, Mode switch for Ultra channel, Gain Ultra channel, Channel switch (A/B), Classic channel volume, Classic channel Mode switch, Classic channel gain, and the input jack.

You may have noticed there are two reverb controls, one for each channel. The reverb unit is an Accutronics Spring Reverb which has a more classic sound. If you want to use a cleaner sounding reverb then you can insert one in the Effects Loop located on the back panel of the amp. It allows you to connect to delay, reverbs, and other effects post preamp section. There’s a switch that allows you to match the gain level for +4dBV (rack gear) or -10dBV (Stomp boxes).

Features

• Incredible Marshall Sound
• All Tube Design
• 100 Watts RMS
• (4) EL-34 Power Tubes
• (3) 12AX7 (ECC83) Preamp Tubes
• Three Band EQ (Treble/Middle/Bass)
• Presence Control
• Tone Shift and Deep Switch
• Effects Loop
• Spring Reverb