Transistor (solid state) vs Valve (tube) equipment

Some common misunderstandings and misconceptions clarified or debunked.
Analog vsdigital, record vs cd, valve (tube) vs solid state (transistor) and so on.
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Transistor (solid state) vs Valve (tube) equipment

Post by superphool » Tue Aug 27, 2019 8:36 pm

Thermionic valves (aka tubes or vacuum tubes) were the first active electronic devices, that could amplify a signal.

The technology was improved steadily from the very first crude devices around 1900 - 1910 through to high technology and high power devices by the 1940s and 50s.

The transistor was invented in the late 1940s and developed very rapidly, starting to replace valves in some applications in less than a decade.

There is a lot of debate about "which is best", especially relating to such as guitar amplifiers and audiophile HiFi equipment.
The simple fact is, with properly designed equipment using either technology, there is no difference in the resulting sound.

In blind tests with a number of both solid state and valve amps, all with the controls pre-set for the same volume and tone, people - including professional musicians - simply cannot tell which type is which.

There are two arguments relating to the claimed differences:

1: When the first transistor-based radios and guitar amps were manufactured, a lot were cut down to the minimum possible components and cost, just to sell larger quantities. The designs and resulting sound quality often poor, giving transistor based equipment a bad reputation when compared to the far more mature and usually better designed valve equipment of the time.

2: Valve equipment typically has a "softer" distortion when overdriven or overloaded, than simple transistor amplifiers.
However that again is very dependent on the specific design of each type of amplifier and transistor amplifiers can be designed to give just the same sound if that is appropriate.

There was a good example a "valve fanatic" lack of understanding on another forum a while ago, someone wanting advice on what type of guitar amp to buy. One of the posts that insisted they should buy a valve amp but also said something along the lines that if they went to the transistor amp instead, they should at least get a "Tube screamer" pedal so they could get the valve overdrive sound.

The Ibanez "Tube Screamer" guitar overdrive pedal is a purely solid state device, using either transistors or integrated circuit amplifiers, depending on the age and version.

In regard to the current revival or fad for valve / tube equipment, be aware that many "valve amplifiers" on the market are at least partly solid state and in some cases entirely solid state, with the valves being purely for show and having no electrical function other than lighting up for effect.

The technical sound quality from a lot of the amps that do genuinely use valves is lower than a good solid state amp can give - but this is then a matter of taste and perception, as in some cases a moderate level of just the right type of distortion can give a more pleasing sound.

That's most obvious with guitar amps, where distortion is often added deliberately to give a richer and more complex tone.

The final conclusion is: Buy whatever type you prefer- but listen to examples first and do not be phooled by exaggerated claims, buzzwords, novelty value or meaningless jargon.

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