Why your Guitar Pro tab sounds like a piano

By machado001 · 3 October 2026

Open your tab file with Tabline

Where a track’s instrument sound comes from

A tab file does not contain audio. It contains a score, and every track in that score carries a General MIDI program number — one integer that says what the track is supposed to sound like. The General MIDI 1 sound set is a fixed list of 128 such programs, grouped roughly into sixteen families of eight, and it is a standard rather than any one program’s invention, which is why the same number means the same instrument everywhere.

Three of those families are the ones a guitarist meets:

Whoever made the file chose a number for each track, or left whatever number was there. Program 1 is a grand piano. If the track you are reading carries program 1, every player that honours the file will give you a grand piano, and it will be right to do so.

On a phone, the sound those numbers come out of is a sound bank: Tabline bundles one General MIDI bank, MS_General v0.1, a fork of S. Christian Collins’ FluidR3Mono, and plays every program through it. The bank is the voice; the number in the file picks which voice.

How to see what instrument a track is set to

This is the part most players hide, and it is the whole answer. In Tabline the track key sits at the right end of the transport bar, labelled with the name of the track currently on the page.

1. Tap the track key. The menu lists every track in the file.
2. Read the small line under each track name. That is the General MIDI instrument the file declares for it — “Acoustic Grand Piano”, “Electric Guitar (clean)”, “Distortion Guitar”.
3. Compare it with what you are hearing. If the line says a piano, the file says a piano, and nothing in the app put it there.

Reading that menu is free, and so is switching tracks — along with opening a file, reading it and playing it back.

Why it sounds like a piano and not a guitar

There are four honest causes, in the order they are worth checking.

1. The track really is a piano track. A full arrangement has keys in it. If you landed on a keyboard part, you are hearing exactly what is written. Tabline opens on the first non-percussion track that has at least six strings and carries a General MIDI guitar program; if the file has no such track, it falls back to the first track with any strings at all, and failing that to whatever the file lists first. On a score with no guitar in it, that fallback can be a piano.
2. The guitar track was saved with a piano program. A transcription typed as pitches, or a part that went through another program on its way to you, can arrive with a program number nobody ever set deliberately. Threads about a Guitar Pro file playing the wrong instrument after a trip through another program are easy to find on notation-software forums, as of October 2026, so the file is the first place to look rather than the app.
3. It is a guitar program, but a sampled one. A General MIDI bank’s “Electric Guitar (clean)” is a set of recorded notes, with no amp, cabinet or pedal in front of it. It will never sound like your rig, and on a dense arrangement it can read as thin or keyboard-like even when the program number is right. Guitar Pro’s desktop program plays through its own sound engine rather than a General MIDI bank, which is why the same file can sound quite different there; user forums’ standard advice for a wrong-sounding track is to switch that engine off and set the MIDI instrument per track, as of October 2026.
4. You are on the wrong track of a multitrack file. The commonest version of “this sounds wrong” is a reader on a part they did not mean to open, which is also why the frets look impossible. Picking the part you want in a multitrack Guitar Pro file takes one tap, and it is worth doing before trusting anything on the page.

Why a drum track has no instrument name

General MIDI reserves channel 10 for percussion, and there each note number is a different drum rather than a pitch, with its own key map instead of an instrument program. So a drum kit has no program number to show, there is nothing for a tab staff to stand on, and Tabline draws those tracks as standard notation. A kit that sounds like a kit is not a coincidence; it is the one family the standard handles separately.

Can you change a track’s instrument on a phone?

Not in Tabline, and it is better to say so plainly than to imply otherwise. Tabline is a reader and a player: it writes nothing back to the file, so the program number it found is the program number it plays. There is no instrument picker, because there is nothing for one to save into.

What it does give you is control over the mix. Setting a track’s volume, muting it and soloing it are part of a one-time unlock — you pay once — and the list that carries those faders names every track in the score with its instrument underneath, so even locked it is the clearest view of what the file thinks it contains. Reading the score with the whole band behind it costs nothing.

If the instrument number itself has to change, that is editing work, and it belongs on a desktop program that writes the format. Fix it there, and the file plays correctly everywhere afterwards — including back on the phone.

When a MusicXML part plays as a low thud instead

One case is ours, not the file’s, and it is worth stating plainly. When a single MusicXML part declares several instruments and tags its notes with them, the engine Tabline uses mis-imports those notes as percussion: in our own test file, 242 of 245 note-ons in such a part came out as MIDI note 0. The page is engraved correctly and the playback pitches are wrong, so the symptom is not a piano but a low percussive thud where real notes should be. It is not fixed and it is not papered over. A file written one instrument to a part — which is what Guitar Pro and Songsterr export — does not run into it. More on the format in opening MusicXML and .mxl on Android.

What to do with a file that sounds wrong

Check the tuning while you are in the file, because a tab in an unexpected tuning sounds wrong in a way that has nothing to do with the instrument. And if every track names something sensible and it still does not sound like the record, you have reached the limit of a General MIDI bank rather than a defect — a good place to stop worrying and start practising.

If the file will not play at all rather than playing the wrong thing, that is a different problem with its own four causes: see when a Guitar Pro file will not open, and what the five Guitar Pro extensions are if you are not sure what you were handed.

The short version

The instrument lives in the file as a number. Read that number’s name in the track menu before blaming the player, and remember that a sound bank is a set of samples rather than an amplifier.