GuitarFlex vs Orange Tree Evolution

Orange Tree Samples' Evolution guitars and GuitarFlex both play acoustic and electric guitars from MIDI on Windows. Evolution is a large line: 38 titles, basses, banjos and a mandolin among them, at $179 for each guitar, sampled, with a pick position that Orange Tree builds with physical modeling, and run in Kontakt Player. GuitarFlex is modeled, not sampled: presets for steel-string and nylon-string acoustic and electric clean, crunch and heavy guitars, an 18.2 MB download, and $79.

What they have in common

• Windows 10 and 11, as a standalone program and as a plugin.
• Acoustic and electric guitars, with an amp and cabinet on the electrics.
• Played from MIDI, from a keyboard or from a file.

Where Evolution stands out

• Mac as well as Windows, on macOS 12 or newer, with AU and AAX as well as VST.
• Many more instruments. 38 titles, with bundles of them sold at a discount.
• Strum keys and complete strumming patterns. GuitarFlex has neither: its strums come from ComposerFlex; from a keyboard or a MIDI file it plays the notes as written.
• A mapping system for articulations, by velocity ranges, MIDI controllers and key switches, with legato samples for slides, hammer-ons and pull-offs.
• Instant double, triple and quadruple tracking, alternate tunings and a capo.

Where GuitarFlex stands out

• No other program needed. Evolution runs in the free Kontakt Player, version 5.6.8 or later, which Native Instruments says needs internet to download, install and activate. GuitarFlex runs by itself.
• Small. An 18.2 MB download that installs at 43.9 MB. Evolution Songwriter is a 5.7 GB download that installs at 5.7 GB, with 11.4 GB free needed during installation.
• $79, against $179 for a single Evolution guitar.
• No account and no online activation. A license key and your email address, entered once for each Windows user on each computer, and one license for one person, to use on all of their own computers.
• It never connects to the internet.
• Four slots (A to D) to switch between sounds or layer them, with Compare, Vary and Randomize, and over 70 sliders from pluck to cabinet.
• Your song to a file. It renders a MIDI file to FLAC, or to WAV with the included command-line renderer.
• Built to play ComposerFlex's band, our songwriting program, on the same PC with no setup. GuitarFlex has no keyswitches. With ComposerFlex it plays down and up strums, open, palm-muted or dead, with Strum spread and Strum fall.

Which to pick

• On a Mac, or in a Kontakt setup you already have: Evolution.
• To strum from a keyboard with ready-made patterns: Evolution.
• On Windows, with nothing else to install, at $79: GuitarFlex.
• If you'd rather have no account and a small download: GuitarFlex.

Owning both

Evolution turns key presses into strums inside Kontakt, and GuitarFlex plays the parts ComposerFlex writes or any MIDI you give it, so the two can share one PC. GuitarFlex's demo is here; for Evolution, go by Orange Tree's own pages. This page doesn't compare how they sound. That's for your ears.

The facts side by side

Every fact about Orange Tree Evolution is from Orange Tree Samples' own pages, checked on 7 November 2026. Prices are list prices in US dollars; sales come and go.

More: virtual guitars compared: modeled and sampled, a table of 25 products, and all about GuitarFlex.

If something here is out of date, write to [email protected] and we'll correct it.

Sources

• https://www.orangetreesamples.com/products
• https://www.orangetreesamples.com/products/evolution-songwriter
• https://www.orangetreesamples.com/products/evolution-electric-guitar-strawberry
• https://www.orangetreesamples.com/license-agreement