MARRS - Intelligent Microphone Array Designer App

[voltronic]

This is going to be right up the alley of certain people here.  Here's the developer's post on Gearslutz copied below:

Hello everyone,
As you know, when recording an acoustic ensemble on location (also in studios), it can be sometimes difficult to decide exactly where to place a microphone array and how to setup the distance and angle between microphones correctly for a desired stereo width and localisation characteristics. To support sound engineers and audio students, we at the Applied Psychoacoustics Lab (APL) of Huddersfield University, UK developed a free app called MARRS for an interactive stereo mic technique simulation. It has an object-based GUI which visualises perceived positions of sound sources for a given microphone array configuration. It is an interactive tool where you can select the number of sources and position them anywhere on a virtual stage (both azimuth and elevation) and set up a preset or customised mic array at certain distance and height. The perceived position for each source in reproduction is visualised interactively as you change the mic configuration. MARRS is also an intelligent tool that can automatically configure suitable mic spacing and angle for the user's desired stereo width. This is done in a way that you can choose a configuration anywhere between 100% coincident and 100% spaced. So MARRS is a useful app for preparing your recording session and also for a sound recording education.

You can download it free from either Apple or Google app store by searching MARRS. Below are the links to the app and a quick start guide and an AES paper that describes the psychoacoustic principle for the algorithm used in MARRS.

- Apple iOS: https://itunes.apple.com/app/id1295926126

- Google Android: https://play.google.com/store/apps/d...marrs&hl=en_GB

- Quick start guide: http://eprints.hud.ac.uk/id/eprint/33675/

- AES paper: AES E-Library » An Interactive and Intelligent Tool for Microphone Array Design

The current version is only for 2-channel stereo, but future updates will include a 3-channel version and a web-audio version with binaural and room simulation.

Hope you find these useful. Any feedbacks are appreciated.

Hyunkook Lee
Leader of the Applied Psychoacoustics Lab
www.hud.ac.uk/apl
University of Huddersfield

[rippleish20]

Interesting.

[morst]

OK I'm messing with it. Not very obvious how it works right off the bat but it does make sense, I think.

The first useful thing I found to play with is the "microphone array" tab. Check out the Preset button top left and pick a configuration you know, like DIN or ORTF or XY90 and see how it sets the app.

Folks with Large Arrays will want to click the Large Setup slider to green. That enables the mics to be up to 8m apart. With it not enabled, centimeter spacing is active, expressed as hundredths of a meter (0.00-1.00 in 0.01 increments)

Oh hey - there's a quick start guide linked from the link that Voltronic linked!
http://eprints.hud.ac.uk/id/eprint/33675/8/MARRS%20Quick%20Start%20Guide.pdf

[Gutbucket]

Thanks Volt, looks like another applied Stereo Zoom app.  I just downloaded it and its a bit clunky at this point for me, but we'll see how it evolves.

Reminder to folks that this only deals with the directional imaging aspects of the direct sound elements in a recording- just one aspect of many in the pantheon of things which affect what we hear via stereo recording an reproduction, and not the most important among them.  However that's not to dismiss the importance of gaining better control over it.  Good tools to help manage imaging can be useful.  If confused by this thing rather than simply frustrated trying to get it to do what you want, a re-read of the iStereo Zoom paper will do much to explain what's going on behind this thing.

[voltronic]

Thanks Volt, looks like another applied Stereo Zoom app.  I just downloaded it and its a bit clunky at this point for me, but we'll see how it evolves.

Reminder to folks that this only deals with the directional imaging aspects of the direct sound elements in a recording- just one aspect of many in the pantheon of things which affect what we hear via stereo recording an reproduction, and not the most important among them.  However that's not to dismiss the importance of gaining better control over it.  Good tools to help manage imaging can be useful.  If confused by this thing rather than simply frustrated trying to get it to do what you want, a re-read of the iStereo Zoom paper will do much to explain what's going on behind this thing.

I think the innovative things is has going for it versus the other apps out there are:
1. The implementation of the height element
2. Being able to view data for multiple sound sources, and move those around and see what it does to the imaging

That said, it's not the easiest to use right now, especially on a smallish phone screen.  On the other hand,

If you check in on the GS thread, you'll see the developer is interested in user feedback.