Originally Posted by: dsp103If you own a nice tube amp (I don't!) then I imagine you can get a great overdrive /distortion sound from it.[/quote]Not necessarily. Many classic tube amps only have so much overdrive on tap. In order to get a completely overdriven tone you might need a good overdrive pedal. You definitely need a boost or gain pedal to tighten (or compress) the tone.
More modern tube amps have more than one channel & are often designed to have an overdrive channel that is competely separate from the clean channel.
So it really depends on the amp.
The entire history of the overdrive pedal is essentially a solution to tightening the low end (bass frequencies) while clarifying & boosting the mids & treble of powerful single channel tube amps like Fenders, Marshalls & Voxes. None of those amps originally had anything like a truly overdriven tone that you need a gain pedal to achieve.
Hence, the early term "treble booster". From there the fuzz & distortion pedals made it possible to have more sustain as well as a variety of "singing, vocal-like" sounds.
Originally Posted by: dsp103Why do people that own these amps pair them with £100 overdrive or distortion pedals?
For the same reason anyone plugs in anything: to get the sound they desire. More precisely in the case of those older amps: sounds you can't get any other way. Or just more timbral options.
And we haven't even talked about other kinds of pedals: reverb, delay, modulation (flanger, chorus, phaser), etc. None of which were included in the design of the original tube amps.
[quote=dsp103]Surely you'd get a much better sound just using the amp on its own than by driving it with a digital pedal?
Most of the older pedals are actual analog. But, the point remains: you can't those certains with the amp alone. You need a pedal.
Your question is actually a very good one! But you are looking at it from the current day perspective of an amazing variety of digital gear. Most of the solutions of amp & pedals you are asking about were deveolped as practical solutions to problems that occured before there were any amps with pre-gain stages, mutli-channel switching & decades before any digital options were available.
Hope that helps!
Christopher Schlegel
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