Classic JCM800 pushed hard with a Tube Screamer in front. The key is the Tube Screamer tightening the low end before the amp.
Signal Chain
Tube Screamer→Marshall JCM800→4x12 V30→Output
PedalTube Screamer
gain
3
tone
5
level
7
AmpMarshall JCM800
bass
6
gain
7
mids
5
treble
7
presence
5
Cab / IR4x12 V30
micSM57
mic positioncenter cap
Notes
Keep the Tube Screamer drive low — it is there for tightness, not for distortion
Don't have Helix?
See the same signal chain mapped to another platform. Knob values carry over as starting points — gain ranges differ between platforms. NAM/TONEX users: the real gear names are what to search for as captures.