All valve amps have a sweet spot where they’re at their most touch-sensitive, notes begin to sustain effortlessly and dynamics start to compress. In an ideal world, our amps would always be dialled into that sweet spot, but that risks incurring the wrath of bandmates, sound engineers and the local constabulary. So, how can we crank our amps but never exceed acceptable volume levels? One solution is to use an attenuator.
Amplifiers generate a lot of electrical energy, but the speakers actually produce the sound by generating sound waves. At the risk of grossly oversimplifying, the more power it’s fed, the louder a speaker will sound. Since the object is to reduce volume without compromising our amp settings, attenuation is usually achieved by placing a device between the amplifier output and the speaker in order to reduce the amount of energy reaching the speaker itself.
Variacs and voltage controllers such as the AmpRx BrownBox can be used to achieve overdrive at reduced volume, but valve
