More on Opus codec and my dreaming

This guy seems to "get it" after having spent some time investigating Opus for use in imbedded systems. I continue to see the practicality of implementing these new codecs (such as Opus and codec2)
in DRM and Digital Voice applications for ham radio and other services.

What excites me most, is the ability to multicast via HF DRM. These codecs make it more than possible to offer multiple voice channels with decent audio quality and bandwidth.

Somewhat off topic but...How about we propose a North American DRM service from the new and improved WRMI? What would be ideal is a DRM - AM simulcast transmission with 2 to 4 audio channels available in DRM.

WRMI is looking to lease more airtime. This would be a great way to do it! Their website says they can offer time for as little as "$1 a minute"! Do we know if WRMI is DRM capable now? Kickstarter anyone?

(Thanks for the Opus article link Benn!)

Japanese DRM fan captures Australian Test Broadcast

Read a rough translation about Hiroshi's catch. I heard nothing about this one guys, sorry. Thanks go to Terje for the tip about Hiroshi's blog.

It is unknown by me how long this broadcast was and to where it was beamed. Shown here is 1105z Monday, 21 January 2013 on 12080kHz. Looks like a crazy high bitrate, which likely hampered good decode for all but directwave listeners.  

Beer-fueled rant to follow: Why in the hell won't some DRM broadcasters "get the memo" about using a lower bitrate as audio quality trade-off for a more robust broadcast? A great compromise is to go with a lower (yet effective) bitrate such as RNZI has proven effective for transcontinental DRM... between 15 and 17 kbps!

Of course, readers of this blog know that I question why DRM is not considering or at least experimenting with the new innovations found in the very bit-rate efficient Codec2!

Relay of National news broadcast using Codec2

"Relay of National news broadcast using FreeDV in SE Australia next Sunday"  
Read the article here.

A ham software application has been developed that implements the new super-efficient Codec2 audio codec. The software is called FreeDV and is freely available with the open source codec. Speech is compressed down to 1400 bit/s then modulated onto a 1100 Hz wide QPSK signal which occupies half the space of a conventional analogue SSB transmission.

We've covered alternative codecs in previous DRMNA posts. What this means is that not only can digital voice be sent and received using off the shelf equipment, but if this were implemented into DRM, a multiplexed signal with with even more voice channels would be possible. The improved intelligibility, higher compression and narrower bandwidth betters all previous voice codecs by a significant amount.

Here is an opportunity to push-the-envelope and make an even more robust and higher-utility implementation of DRM. Will it happen? We shall see. It does follow the "open source" rubric we always hear from the DRM Consortium.