Valve Amplifiers versus Solid State Amps

Guitar amplifiers which utilise valves have been around for over 50 years and are still as popular today as ever. Many musicians feel that the valves bring warmth to the sound of the instrument, mainly due to the relaxed top end frequencies and soft bass, but with an excellent degree of mid-range tones.

Solid state amplification was introduced in the 1970s and became popular due to it’s clarity of sound reproduction. Here we will look at and compare both technologies to see the relative advantages of each.

Valve Amplifiers

Known as a valve audio amplifier here in the UK or a vacuum tube audio amplifier in the US, this type of amp is used for sound recording, reproduction and reinforcement. A typical example would be the Marshall C501 combo amp which uses valves at the power and output staging ...

While solid state devices prevail in most audio amplifiers today, valve audio amplifiers are still used extensively in the music business where their audible characteristics are considered preferential. A good example of a solid state amplifier would be the Vox AC15VR that is built using solid state technology

Valve amps have the following technical advantages over their solid state counterparts:

• In comparison to semiconductors, they have a low drift across a wide range of operating conditions.
• Failed valves are easily replacable, whereas solid state amplifers entail a much more complicated process.

The Solid State Amplifier

Valve amps have various disadvantages in comparison to the solid state amplifier:

• They are typically bulky and heavy units requiring power transformers, although they are generally direct-coupled and don’t require output transformers
• The valve performance will worsen over time, eventutally resulting in complete failure. If maintained appropriately, performance is excellent and will have a decent lifespan.
• They require a warm-up period (of a few minutes or so with modern amplifiers) to produce optimal tone.

Modeling amps simulate the classic sound emitted from the most well known amplifier and effects, by using digital processing, although analogue units are also available. This technology offers a wide range of guitar tones and effects, as well as cabinet simualtion so it can be recorded without the need for a microphone. There was a time when first generation modeling amps were deemed inferior by many in comparison to more traditional amplifiers, simply because the digital simualtion didn’t really capture the way that a real valve amp performs at different volume levels.However the most recent generation of modeling amplifiers has now addressed this and amps such as the Vox VT 20+ and Vox VT40+ will now also emulate the differential in tone that occurs naturally at low, medium and high volume levels ..

Whichever amplifier you choose, be sure to try it with your own guitar and any onstage effects that you may use on a regular basis.