Welcome! You have reached the little online universe of Andreas Melcher.

This page should give you a short overview about what I'm doing in my spare time to

If you have questions or just want to chat about anything else here are some possibilities to connect:

Twitter LinkedIn XING Twitter GitHub

Some of my current projects...

screenshot of the video transcription editor

Online Youtube Transcription Editor


Last year I wrote notes when I watched youtube videos so my coworkers can understand faster watching the same videos. The idea was: whoever watches a video first can help the others by marking chapters and important parts.

I realized that it also helps me remembering the content and of course I find again everything very fast if I want to re-watch a specific part of a video.

Now that I try to write notes every time I watch an inspiring or informative video I need a simpler way of transcribing. So I started to build this editor. If you like to learn and want to help others learn faster - please try this out and give me feedback how to make it even easier to write and watch simultanously.

ServerJava/Tomcat (Nginx for caching and static resources), Mongo-DB, JAX-RS/Jersey, logback, OWASP Java Html Sanitizer, Json, JavaMail API
ClientTypeScript, HTML, CSS, Bootstrap, JQuery


Open source @ GitHub

With the help of this project I can define "Allowed Graphs" a data object has to follow while running through the code by passing "milestones".

I added time measurement to those milestones as well and a GUI to visualize the recorded path of such an object. Now I can see in realtime how parts of the code get faster or slower while I change the environment at runtime.

I used it for example to understand performance issues we had with a database. We ran our load tests and watched the visualization while we changed database procedures. We saw how some requests became faster and others became slower in the same second when we changed transaction isolation levels, indexes or stored procedures. That's one of those moments where you love to be able to do stuff like that :D

Server For serving the browser GUI for live monitoring: Jetty, WebSockets to push real time data to the client, focus on concurrency and performance
Client Chart.js, SVG, HTML, CSS, Bootstrap, JQuery

screenshot of the amroc room mode calculator

amroc - the Room Mode Calculator


Around 15 years ago I started to learn Java. The first version of my room mode calculator "amroc" was my first real project back then. This second version replaced the old one when HTML5 started to lift off and Java Applets made more and more problems. Again this baby became my first larger project for a new language.

Room Modes are a very specific topic but thanks to the many users and the long time this calculator is online now google is listing me on top of all alternatives. This baby shows that in the long term quality is more important than SEO (Search Engine Optimization).

ClientHTML, JS, Web Audio API, CSS, JQuery
Also have a look at the mobile version of this website!

screenshot of the amray raytracing sketchpad

amray - do raytracing experiments


Amray is a sketchpad for 2D raytracing experiments. Primarily it's made for acoustic raytracing (Geometrical acoustics), but you can also use it for example to see how rays of light are reflected by mirrors.

Every now and then I need to think about bending or splaying some walls or room acoustic elements to guide sound in specific directions. Besides that I often saw people drawing sketches to explain how sound behaves when reflected.

This tool is meant for both, teachers and acousticians to do fast ray tracing experiments.

ServerJava/Tomcat, GWT (Google Web Toolkit), Java Mail API

screenshot of my interactive online resume

My Interactive Curriculum Vitae


This site is more of a placeholder for future experiments with JS visualization frameworks. For now I added some data about my life and want to try different frameworks to visualize the s*** out of this and additional data.

At the moment its

ServerJava/Tomcat, MySQL, Logback, Json
ClientHTML, JS, CSS, JQuery, vis.js

screenshot of my interactive online resume

My Thesis in Music Science as Website


I always planed to not write that amount of text to let it rot in dusty bookshelfs. It's a great pleasure to see the number of users reading and discussing it in the realms of social media. Spreading knowledge and giving back to the www is the best you can do with your time and money ;)