Understanding overdrive

The overdrive effect, in its most fundamental understanding, is a device which increases the gain levels of your guitar input so that there will be a driven output at the amplifier. The understanding here is that the typical overdrive unit does not drive your signals upon receiving them but adds on more so that the drive would finally take place at the final destination; your amplifier. The overdrive produces a very mild effect, much typified by the grand daddy of all overdrive units, the Ibanez TS9.

It is, in this light, used as an enhancement for an already overdriven amplifier for a pile-on effect so we hear an increase in intensity. It can also be used as a primary source of overdrive to add minimum levels of drive for one's guitar tones, as superbly illustrated by the late Stevie Ray Vaughan.

Why is there much confusion between the overdrive & the distortion effect? This is simply because many overdrive offerings today are varied in their intensity grades, sometimes overlapping into the distortion capacity. We'd be thinking why an overdrive unit like BOSS' OD-2R for instance, has so much drive when the basic understanding of this effect unit simply states it to be a polite effect in terms of its intensity. There is much argument over the overdrive understanding but let it be known that it is one which enhances gain in order to produce a drive effect, not a driving effect per se.