# Glossary Short explanations of MatchPatch terms. These are written for musicians, not software developers. ## Adjusted File The Helix file MatchPatch saves after calculating level changes. This is the file you import back into the Helix after checking the results. See also: [Measurement And Adjusted Files](concepts/measurement-and-adjusted-files.md). ## Analysis Interval How often MatchPatch checks loudness while listening through the recorded audio. A shorter interval checks more often. ## Analysis Window The length of audio MatchPatch listens to for each loudness measurement. A longer window can be steadier, but it needs enough recorded audio. ## ASIO A low-latency Windows audio driver type often used by audio interfaces and processors. If you use hardware mode, the Helix audio device may appear through ASIO. ## Backend The way MatchPatch gets sound to measure: - hardware measures a real Helix; - loopback tests the app without a Helix; - simulated uses a fake processor for testing. See also: [Backends](concepts/backends.md). ## Block Size The audio buffer size used while recording and playing audio. Most users can leave this at `0`, which lets the audio system choose. ## Crest Factor The gap between the loudest peaks and the average energy of a sound. A sharp, spiky rhythm part has a higher crest factor than a compressed lead tone. See also: [Crest Factor](concepts/crest-factor.md). ## Custom Adjustment A manual loudness exception for one preset snapshot. For example, you can tell MatchPatch to make snapshot 2 of `01A` 1.5 dB louder than the normal target. ## dB Decibels. Guitar processors use dB to describe level changes. A `+3 dB` change is louder; a `-3 dB` change is quieter. ## Deadband A small level-change range where MatchPatch may leave things alone. This avoids tiny edits that do not matter musically. ## DI Direct input. A clean guitar recording before amp, cab, and effects. MatchPatch plays this clean recording through every preset so each preset is measured from the same performance. See also: [Reference DI](concepts/reference-di.md). ## Gain Delta The level change MatchPatch calculated for a snapshot. In the table, this is the Delta dB value. ## Hardware Mode The backend that measures a real Helix. Use this for real results. See also: [Hardware Measurement](workflows/hardware-measurement.md). ## Helix The Line 6 Helix guitar processor family. MatchPatch currently focuses on Helix `.hls` setlists and `.hlx` presets. ## LUFS A loudness measurement that is closer to perceived loudness than a simple peak meter. MatchPatch uses LUFS to decide how much each snapshot should move up or down. See also: [LUFS And Loudness](concepts/lufs-and-loudness.md). ## Loopback Mode A no-hardware mode where MatchPatch measures the reference DI directly. It is good for learning the app, but it does not measure your Helix tone. See also: [Test Without Hardware](workflows/test-without-hardware.md). ## Measurement CSV A file containing measured loudness and crest-factor results for each preset and snapshot. Most musicians do not need to open it. ## Measurement File A temporary Helix file created for measuring. It changes routing so MatchPatch can send the DI into the Helix and record the result. > Warning: > A measurement file is not meant for live playing. See also: [Measurement And Adjusted Files](concepts/measurement-and-adjusted-files.md). ## MIDI The control connection MatchPatch uses to switch Helix presets and snapshots during hardware measurement. ## Output Block Level The final output level inside a Helix preset. MatchPatch adjusts this level per snapshot to balance loudness. See also: [Routing And Levels](concepts/routing-and-levels.md). ## Patch Another word for a preset. On Helix, a patch or preset lives in a slot such as `01A` or `12D`. ## Pre-Roll Silence recorded before the reference DI starts. It gives the audio recording a little room before the performance. ## Post-Roll Silence recorded after the reference DI ends. It gives the audio recording room for latency and short tails. ## Preset A stored Helix sound, usually one song, tone, or rig. ## Reference DI The clean guitar WAV MatchPatch plays through every selected preset. A good reference DI should match your real playing style. See also: [Reference DI](concepts/reference-di.md). ## Round-Trip Latency The small time delay caused by sending audio out to the Helix and recording it back into the computer. ## Routing The path audio takes. In hardware mode, the reference DI leaves the computer, goes into the Helix, and the processed sound comes back to the computer. See also: [Routing And Levels](concepts/routing-and-levels.md). ## Simulated Mode A no-hardware mode that pretends to be a processor. It is useful for testing the workflow, but it is not a real Helix measurement. ## Snapshot A variation inside one Helix preset. For example, one preset might have Clean, Crunch, Lead, and Solo snapshots. ## Solo Boost Extra level added to snapshots that MatchPatch recognizes as solos. The default solo boost is 3 dB. See also: [Snapshots, Solos, And Ignored Snapshots](concepts/snapshots-solos-and-ignored.md). ## Steering The automatic preset and snapshot switching MatchPatch performs during hardware measurement. ## Target LUFS The loudness MatchPatch tries to match. If a snapshot is below the target, MatchPatch raises it; if it is above the target, MatchPatch lowers it. ## USB Channels The audio paths between the computer and Helix over USB. MatchPatch needs the playback and recording channels to match the Helix routing. ## WSL And WSLg Windows Subsystem for Linux and its graphical app support. Some users run the MatchPatch GUI from WSL while hardware measurement uses a Windows audio setup.