AES Journal Forum

Shortest Impulse Response Measurement Signal That Realizes Constant Normalized Noise Power in All Frequency Bands

Document Thumbnail

It is desirable that the measured acoustic impulse response has constant normalized noise power (NNP) in all frequency bands. However the conventional measurement signals aimed at achieving this property were derived intuitively, and the theoretical background is insufficient. In this work we first theoretically derived the relational formula that the measurement signals must satisfy for the measured impulse response to have constant NNP over all frequency bands. This formula includes all the measurement signals that achieve constant NNP. We then found the shortest (equivalently, the minimum energy) measurement signal among them. We call this signal the bandwise minimum noise (BMN) signal. Experiments to measure the room impulse responses were carried out. The experimental results confirmed that the impulse responses measured by the BMN signal had almost constant NNP in all frequency bands. Also, it was confirmed that the BMN signal achieved the required NNP for reverberation time measurement with the shortest signal length as compared with the conventional measurement signals.

Open Access


JAES Volume 70 Issue 1/2 pp. 24-35; January 2022
Publication Date:

Download Now (1.1 MB)

This paper is Open Access which means you can download it for free.

No AES members have commented on this paper yet.

Subscribe to this discussion

RSS Feed To be notified of new comments on this paper you can subscribe to this RSS feed. Forum users should login to see additional options.

Start a discussion!

If you would like to start a discussion about this paper and are an AES member then you can login here:

If you are not yet an AES member and have something important to say about this paper then we urge you to join the AES today and make your voice heard. You can join online today by clicking here.

AES - Audio Engineering Society