Classic rock tones are often very sought after by guitar players, thanks to their brilliantly rich, simplistic overdriven sound and edgy rocking tone. Both amplifier companies and effects pedal manufacturers’ alike offer a variety of ways in which you can get those classic crunchy tones. Distortion and overdrive pedals marketed to this kind of player include most famously the Boss DS-1 and the Ibanez TS808 (or the slightly more available and cheaper TS9). These pedals are simpler stomp boxes which boast limited control pots for volume, drive and tone.
The reason these two pedals in particular are recommended for classic rock tone is that when working through a clean amplifier channel, they create a standard general distortion suitable for a lot of situations, and when used with an overdrive channel they push the valves into a more natural distorted tone.
This is the secret to getting true classic rock crunch tone; it all lies in having a real tube amplifier. Players like Jimmy Page and Angus Young famously relied heavily on using the natural distortion of a tube amp breaking up the tone with higher gain. This is a very natural sounding crunchy overdrive that sounds wonderful for rock rhythm guitar. When an overdrive pedal is added into the mix before the pre amp, the combination is simply wonderful. A good overdrive pedal will push the pre amp of a vintage amp smoothly into a rocking crunch that will make you feel nostalgic for the days when long hair and tight leather trousers were normal things for a guy to have.
Add a compressor before the overdrive to get boosted, sustained tones which are great for classic rock lead, or put a good distortion pedal after the overdrive pedal to step up the gain and stack some heavy clipping on top of the tone for a really heavy, creamy vintage tube sound.