devices · Helix Rack · reference · blocks, paths and DSP
blocks, paths and DSP
Presets are made of blocks, laid out on paths
A path is a chain of eight block positions. Path A is the main one. Path B is a parallel branch that leaves A at a Split and rejoins it at a Merge. Devices with two paths give you Path 1 and Path 2, each with its own A and B: four rows in total, with two separate DSP chips behind them.
Helix 3.80 Owner's ManualA block that will not add has usually hit a cap, not a full CPU
There are hard caps on particular kinds of block, and they bite long before the processing meter looks alarming. Free DSP does not unlock any of these.
Four in total, and no more than two on either path
A wet/dry/wet rig hits the two-per-path half of the rule first.
Helix 3.80 Owner's ManualFour Single Cabs, two per path, or two Dual Cabs, one per path
An Amp+Cab block spends one of your cab slots. If cabs run out before amps do, that is where they went.
Helix 3.80 Owner's ManualFour 1024-point, two per path; or two 2048-point, one per path; or two Dual IRs, one per path
The longer IR costs twice as many slots. The block itself does not say so.
Helix 3.80 Owner's ManualOne per path
Feedbacker, Poly Sustain, Poly Detune, Poly Pitch, Poly Wham, Poly Capo and 12 String. Any one of these can eat up to half the DSP for its whole path.
Helix 3.80 Owner's ManualOne per preset
One per preset, not one per path. A two-looper preset will not build.
Helix 3.80 Owner's ManualOne instance of each per preset
It counts whether it appears as a Return block, an FX Loop block, or as an input on a path. All three share one budget.
Helix 3.80 Owner's ManualBypassing a block does not give you its processing back. If you are trying to make room, delete it.
Six changes that free up real room
Stereo costs twice as much as mono
The stereo version of an effect uses roughly double the DSP of the mono version, and a Dual Cab roughly double a Single. If a preset is one block short, the cheapest fix is usually to make something mono that did not need to be stereo.
Helix 3.80 Owner's ManualNewer cabs are far cheaper than Legacy cabs
The IR-based Cab and IR blocks introduced in firmware 3.50 use significantly less DSP than the original Legacy Cab blocks. Swapping a Legacy cab for its current equivalent can buy back a whole block.
Helix 3.80 Owner's ManualOne amp plus a Dual Cab beats two amps
For two cabinet flavors, use a single Amp block into a Cab > Dual instead of two parallel Amp+Cab blocks. You get most of the variation for a fraction of the cost.
Helix 3.80 Owner's ManualUse snapshots instead of duplicate blocks
Two copies of the same amp with different settings is the expensive way to do it. One block, with a snapshot changing its parameters, is free.
Helix 3.80 Owner's ManualLook for a “Simple” version
Several categories include Simple blocks that do the same job for less DSP. They sound the same and have fewer parameters.
Helix 3.80 Owner's ManualAmp models are not all priced the same
Some models use noticeably more DSP than others in the same category, and this is most true of amps. If one preset will not fit and a near-identical one will, the amp choice is the usual reason.
Helix 3.80 Owner's ManualSuper Serial
You can run more than eight blocks in a row. Move the Merge block down to path 1B and drag the Split all the way to the right, past the last block. Path B then continues A instead of running parallel to it. That is 11 blocks in series instead of 8. Route 1B's output into path 2 to chain all four rows, for up to 32 block locations, DSP permitting.
Helix 3.80 Owner's ManualPreset Spillover
Changing preset unloads every block and loads new ones, so delay and reverb tails get cut off. That is the cost of switching, not a fault.
Hold ACTION and press HOME, or turn on Preset Spillover in Global Settings > Preferences, and confirm. Trails now carry across preset changes.
It removes Path 2 entirely: spillover spends one of the two DSP chips. Presets still load, but only their Path 1 blocks. Anything on Path 2 stays saved and comes back when you turn spillover off. Loopers do not spill over either way.