Two classic amps, two different voices. The Marshall JCM800 is midrange-forward 80s rock crunch; the Marshall JCM900 is brighter, higher-gain 90s Marshall with diode-clipping preamp saturation. Here is how their settings and the records made on them compare.
| Knob | Marshall JCM800 | Marshall JCM900 |
|---|---|---|
| Gain | 6.5 | 6.5 |
| Bass | 6 | 6 |
| Mid | 6 | 6 |
| Treble | 7 | 6.5 |
| Presence | 6 | 5.5 |
Averaged from 84 (Marshall JCM800) and 16 (Marshall JCM900) famous recordings. Out of 10.
Go Marshall JCM800 if you want midrange-forward 80s rock crunch. Go Marshall JCM900 for brighter, higher-gain 90s Marshall with diode-clipping preamp saturation. But the real point: you do not need either one. GuitarToneAdapt takes any tone recorded on these amps and re-dials it for the amp and guitar you actually own — free.
🎛️ Get either amp’s tones on YOUR rig — free →Neither is "better" — they are voiced differently. Marshall JCM800 is midrange-forward 80s rock crunch; Marshall JCM900 is brighter, higher-gain 90s Marshall with diode-clipping preamp saturation. Pick by the tone you want, then adapt the settings to the amp you actually own.