Built for the four instruments that sit at the back of the section.

Five curricula cover violin, viola, cello, double bass, and music theory, totalling 634 lessons. A composition studio with a proper notation editor. 89 annotated orchestral excerpts with the trouble spots and failure modes that decide how they land in an audition. 106 glossary entries and 10 long-form guides, all free and open to anyone.

The organising idea is simple. A string player needs to see the note on the staff, hear its place in the harmony, and know where the finger goes. Every lesson keeps the staff, keyboard, and the student’s own fingerboard synchronised because the gap between those three views is where most students stall.

Playback uses recordings of real instruments rather than a general MIDI synthesiser, because a violin and a cello playing the same written pitch are two different sounds and a student learning to hear their own instrument should hear their own instrument.

The violin, viola, cello short-bow and pizzicato, and double bass sets are selected roots from VSCO 2 Community Edition by Versilian Studios, released under a CC0 public domain dedication, recorded by Sam Gossner and Simon Dalzell with original sample cutting by Elan Hickler. Arco stores an evenly spaced subset locally, encodes it as AAC for fast web playback, and normalises every filename to scientific pitch notation with middle C as C4.

The guides, the glossary, the printable charts, and the repertoire pages are free and need no account. They are written to be complete for a reader who never subscribes. That is the whole point, and it is also the only version of this that earns a link or a citation.

• ·The answer comes first. A guide that opens with three paragraphs of preamble has failed its reader.
• ·Anything checkable is stated explicitly, including pitches, tunings, clefs, positions, and standard fingerings, so a teacher can verify it rather than take it on trust.
• ·Every guide shows the date it was last reviewed, and that date reflects an actual review.
• ·Nothing is a product pitch in disguise. Where Arco is relevant it is named at the end, not woven through the advice.
• ·Testimonials appear only with recorded consent from a real student. There are no invented reviews and no invented ratings anywhere on this site.

It is not a replacement for a teacher. A teacher watches your bow arm, hears your tone in a room, and adjusts a hand position with one touch; no software does that. Arco is built to bring structure between lessons through theory, note reading, practice routines, and repertoire research, so lesson time can be spent on the things that genuinely need a person.

It is also not an ensemble. Playing with other people is the reason to learn an orchestral instrument at all, and nothing here substitutes for a rehearsal.

Pitch detection for the tuner and the practice tools runs on your own device through the Web Audio API. Microphone audio is not uploaded for those tools, and they need no account. The full detail is in the privacy policy.