• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

URSA Mini 4.6K (First Generation) ADC Measurements

Weeb Labs

Addicted to Fun and Learning
Joined
Jun 24, 2020
Messages
604
Likes
1,417
Location
Ireland
Greetings!

If you own an URSA Mini 4.6K, you might occasionally have wondered just how well the onboard ADC stage performs and whether it is suitable for use as a field recorder. Today, we shall find out.

First, the SINAD measurement.

ursa mini 4.6k.png


Not bad at all for an on-camera ADC. We're sitting at 90dB, with noise down at -110dB. Few microphones are going to be this quiet!

Now on to the frequency response.

ursa mini 4.6k_FR.png


More or less flat, rising toward 20Hz.

Finally, let's have a look at the 31-tone test and see how things look in the IMD department.

ursa mini 4.6k_IMD.png


Rising with frequency, which is typically what we would expect.

I have almost certainly just unlocked the kitchen sink achievement for devices measured on ASR! ;)

Thank you for reading and hopefully this has been of help to somebody.

Troy (Weeb Labs)
 

pozz

Слава Україні
Forum Donor
Editor
Joined
May 21, 2019
Messages
4,036
Likes
6,827
OP
Weeb Labs

Weeb Labs

Addicted to Fun and Learning
Joined
Jun 24, 2020
Messages
604
Likes
1,417
Location
Ireland
Nice!

What is the FFT size?

And do you mind describing the measurement chain?
The FFT size was 64k.

The measurement chain was quite simple. An SU-8 channel was connected to one of the URSA’s XLR inputs, with the camera set for line level. The inputs were adjusted for unity gain and generator level adjusted to peak just below 0dB to be safe.

A few seconds of RAW video were then captured and the corresponding WAVs contained the results.
 

pozz

Слава Україні
Forum Donor
Editor
Joined
May 21, 2019
Messages
4,036
Likes
6,827
The FFT size was 64k.
Was the -110dB figure a noise calculation produced by REW? Noise might be significantly higher due to FFT gain (10*log(bin size/2), or 45dB for 64k).
 
OP
Weeb Labs

Weeb Labs

Addicted to Fun and Learning
Joined
Jun 24, 2020
Messages
604
Likes
1,417
Location
Ireland
Was the -110dB figure a noise calculation produced by REW? Noise might be significantly higher due to FFT gain (10*log(bin size/2), or 45dB for 64k).
Yes. The noise floor is raised at 32k but does not change above 64k.
 
Top Bottom