Automated Measurement Turntable Controlled by REW

[Public Fidelity]

Hey everyone!

Just wanted to share a quick project I recently worked on: an automated loudspeaker measurement turntable controlled directly from REW (Room EQ Wizard).

I built this turntable to streamline my loudspeaker measurements and make the process more efficient. With REW's API-control (Beta release), I can precisely rotate the turntable to capture data at different angles, allowing for spinorama measurements without the need for manual adjustments. The setup has been a game-changer for me, saving time and ensuring accuracy in my measurements.

Here are some pictures with a small explainer:

The table (made from the Audiomatica Medusa project files)


Table in action


I wrote a custom controller that uses the REW-API (in beta release)
This is log from controller:


It uses the measurement 'Increment' number as rotational distance input for the turntable.
The 'Repeated measurement' feature in REW allows for automated repeat.


Example of 0 - 80 degrees measurement sequence (gated)


Happy to answer any questions or share more details if anyone's interested.

 

[kevmoso]

Very interested in this! More info please? Post your "custom controller" perhaps?
I didn't see printable files for the Audiomatica Medusa parts. Is this an Audiomatica members only thing? Not difficult to reproduce/improve in 3d but who doesn't like the easy button?

 

[kevmoso]

Also WTH kind of speaker did you measure with that nice of a polar response from 200 to 8-9khz?

 

[Public Fidelity]

Very interested in this! More info please? Post your "custom controller" perhaps?
I didn't see printable files for the Audiomatica Medusa parts. Is this an Audiomatica members only thing? Not difficult to reproduce/improve in 3d but who doesn't like the easy button?

You have to subscribe (for free) on the medusa project page to download the files.

It is a great little project and thought it would be nice to have it integrated with REW.

I used a single motor driver and with an Arduino Nano, instead of a full CNC-shield. I thought the Gbrl-firmware to be too cumbersome for a simple rotation operation, so I wrote my own Arduino program that listens to serial commands.

The 'contoller' is a small executable (written in Go) that connects to the arduino and acts as a listener for REW-API subscription events. It takes care of converting a measurement event into a serial command for the turntable.

 

[Public Fidelity]

Also WTH kind of speaker did you measure with that nice of a polar response from 200 to 8-9khz?

That is the Peerless TC7FD00-04 in a prototype. The project is a miniature three-way with listening window optimised performance.

Poster preview:

I was actually surprised by it's raw response.