Note: All this week, we’ll be publishing short posts from the 2017 NAMM Show in Anaheim, California. It’s a huge exhibition, so we’ll focus on what we try to do best: cover the field of music notation software and related technology.
This post is about Soundslice, the web-based music-learning software with an innovative music player.
There are only so many hours in a day, and until a day-stretcher is invented, when it comes to covering software for this blog I’ve been focused mostly on the products I use regularly. Those tend to be desktop notation apps like Finale, Sibelius, and Dorico, and, increasingly, tablet notation apps like StaffPad, which all install directly on your device of choice and focus on creating music notation.
There’s a whole other world of music software out there, of course, and I wish I have had a chance to cover some of the fascinating products that don’t fit neatly into that description above. One of the most interesting products is Soundslice, music software that is totally browser-based and focused on the music education market.
Chicago-based Soundslice was created by Adrian Holovaty and PJ Macklin to, as they say, “solve a major pain point in their lives as musicians: the process of learning a piece of music is way too inefficient.” They created the Soundslice player — a hybrid audio player / notation viewer that syncs notation with real audio or video, allowing someone to learn a piece of music while reading and hearing it.
Along with their colleague Corey Richardson, they develop a product that has three main parts: a store that sells lessons and transcriptions; a tool for teachers to create interactive lessons; and a way to license the technology to other companies.

The result is a beautiful way to experience notated music that handles both traditional notation and guitar tablature, and automatically re-sizes as you adjust your browser, for any device, whether it’s a phone or a large-screen desktop or anything in-between.
I headed over to Booth 1670 to visit with Adrian to learn more and to see how things were going.
Adrian’s background is in journalism and software development. “I worked at newspapers for a few years, most recently the Washington Post, building web applications in the service of journalism,” he said. “Then I started a company called EveryBlock that did a “news feed for your city block” — so-called hyperlocal news. Along the way, I helped create Django, which is a free, open-source web development toolkit used by many programmers around the world.”
Musically, Adrian’s a guitarist who plays fingerstyle and gypsy-jazz music. “I gig relatively frequently in Amsterdam, and I’ve toured in the U.S. with a few gypsy-jazz bands, so you could say I’m a semi-professional musician in that I get paid to perform music,” he said.
His interesting in transcribing music led to his idea for Soundslice. “I transcribe a lot of music in my spare time, always with the goal of learning new licks and tricks,” Adrian said. “The music I generally learn — like most people playing jazz/pop/rock — is music that originated with a performance recording, not with notation. For example, Django Reinhardt wasn’t performing his masterful guitar solos from sheet music — they were improvised.”
For people like Adrian who learn from recordings, “there are some great tools for ‘reverse-engineering’ music — tools that give you the ability to slow down the audio without changing pitch, loop sections, isolate parts of the stereo spectrum, and even guess the notes/chords in some cases,” he said.
“But, for me,” Adrian continued, “these tools have always fallen short because they don’t help you document what you’ve learned. You have to use a separate tool (notation software, or just paper) to write down your hard-earned reverse-engineering results. Switching between audio-reverse-engineering tools and notation tools is time-consuming and error-prone. I wanted there to be a transcription tool that combined everything — the transcription tools plus the notating — for a much more efficient process.”
Soundslice has existed in its current form since spring 2014 and has been continuously updated since then. Before that, starting in late 2012, it was a tablature-only tool for transcribing YouTube videos.
“Its main purpose,” Adrian said, “is to be the Internet’s finest music learning and practice experience. When you learn a piece of music with Soundslice, you’ll do it faster and more effectively than by other means. We achieve that by combining music notation with real audio and video recordings — giving you a beautiful interface for deeply studying a piece of music. And, if you teach music, you can use Soundslice to create these synced music scores.”
I asked Adrian how Soundslice compares to other apps, including the web-based music notation platform Noteflight. “Soundslice and Noteflight are similar, at face value, in that they’re web-based and have custom notation rendering engines. But the use cases are completely different,” he said. Noteflight is for notating music; Soundslice is for learning and practicing music, with a focus on learning from recordings. Noteflight is for composers; Soundslice is for performers who want to learn pieces others have composed.
“Noteflight has prioritized having nice synthetic (MIDI-like) sounds — because their customers want to compose arbitrary music, for which performance recordings do not yet exist. Soundslice has prioritized having flawless audio/video-to-notation syncing features — because our customers want to learn by hearing real humans perform,” Adrian said.
Soundslice’s focus, Adrian said, is “on syncing music notation with real recordings, and building rich practice tools around that, is unlike any other product. On the notation side, ‘responsive’ notation — i.e., the fact that notation reflows to fit your device’s screen width — is the best in the business. Soundslice is as smooth as butter. Try resizing your browser window on this page, for example.”
Adrian demonstrated how and why Soundslice resizes music in this video today from the NAMM exhibition floor:
Adrian described their syncpoint editor, “which is how you sync notation with a recording. It’s beautiful, fun and easy to use — and it handles any musical situation, from metronomic precision to super-expressive, out-of-time playing.”

Soundslice has several customer bases, Adrian told me:
On the student side — intermediate-to-advanced musicians who are hungry to learn new material, who are self-learners, and who are very comfortable using digital learning materials.
On the teacher side — music teachers who want to improve the efficacy of their teaching, by giving their students rich instructional material.
On the website side — owners of music-education websites who want to dramatically increase the quality and effectiveness of their instructional material.
Soundslice is really slick when it comes to layout and formatting, especially when you take into account that it’s web-based and has to account for multiple platforms and devices. “Any competent web designer will tell you that the hardest — and most important — thing about web design is that you aren’t just designing a website for one screen, you’re designing anabstract concept of a website that could be viewed in any number of different screen sizes, browser versions and device types,” Adrian said.
“Soundslice applies this classic web design philosophy to music notation. It’s an entire music-engraving system running in your web browser — with the core tenet that we cannot know, ahead of time, what screen the student will be on,” Adrian said. “As anybody who has built a music-engraving system can tell you, there are many interesting edge cases in automatic engraving — so making a general-purpose engraving engine that doesn’t know, ahead of time, some fundamental parameters such as screen size…that’s a rather hard problem!”
“We are somewhat unique,” he continued, “in that we deliberately throw away some layout and formatting. For example, we do not import line breaks. That’s because we want to tailor the notation to whatever screen size the student is using. And given that people use Soundslice for learning, not performance, the location of line breaks isn’t nearly as important as in, say, a published piece of music.
“There have definitely been many problems along the way, and there continue to be many corner cases of notation that we don’t handle as elegantly as we should,” Adrian conceded. “This is a long-term project, and I can’t think of any notation software that’s perfect. But for the majority of music — especially for the type of music that people use Soundslice for — the rendering is quite good.”