Pedals that stack with the Blackstar HT-20RH MkIII

pushes an amp at the edge of breakupPushes an amp already sitting at the edge of breakup over the line. (edge of breakup → clean boost)

Into Blackstar HT-20RH MkIII, Analog Man King of Tone is right at home: it's built around Marshall-style amps

Goes in front of the amp

fills a frequency gapFills in a frequency range the other side doesn't cover, instead of piling more onto what's already there. (transparent → mid-forward)

The transparent tone has headroom to spare — Catalinbread RAH leans it toward mid-forward to fill it in

Goes in front of the amp

clean platform takes the driveA clean, high-headroom stage takes on dirt it can't generate by itself. (transparent → high gain)

JHS Angry Charlie's own voicing points at Marshall-style amps, and Blackstar HT-20RH MkIII delivers it

Goes in front of the amp

sits in the right chain slotPlaced for where it does its job cleanly in the chain, not for a tonal interaction with the anchor.

Keep EarthQuaker Devices Grand Orbiter after Blackstar HT-20RH MkIII in the signal chain, clear of Blackstar HT-20RH MkIII's own gain stage

Goes in front of the amp

shapes the dynamic responseShapes how the tone responds to picking dynamics rather than its frequency or gain. (dynamic → compressed)

JHS Pedals JHS Whitey Tighty leans toward compressed, and that's a real, usable character to pair with

Goes in front of the amp

sits in the right chain slotPlaced for where it does its job cleanly in the chain, not for a tonal interaction with the anchor.

Keep FoxGear EchoSex in Blackstar HT-20RH MkIII's effects loop, clear of Blackstar HT-20RH MkIII's own gain stage — goes in the amp's FX loop (or last, into a clean amp)

Sits in the amp's effects loop

sits in the right chain slotPlaced for where it does its job cleanly in the chain, not for a tonal interaction with the anchor.

Put Strymon Brigadier dBucket Delay in Blackstar HT-20RH MkIII's effects loop, clear of Blackstar HT-20RH MkIII's own gain stage — goes in the amp's FX loop (or last, into a clean amp)

Sits in the amp's effects loop