KBS from Sofia in DRM/AM Simulcast

The korean national service KBS is currently testing DRM-AM simulcast. This means the same service is transmitted side by side on co channels. One channel contains the service broadcasted in DRM mode, the next channel contains the same service via AM. This gives the opportunity for some nice comparisons between DRM and AM stability and audio quality. Find two audio snippeds below.
The transmissions will be every evening from 19UTC to 20UTC on 5875kHz (DRM) and 5885kHz (AM) – source www.drm.org

The screenshot shows a part of the radio band yesterday evening. Unfortunately the conditions to Sofia had been really poor. You can see the both signals of KBS and some much stronger signals from other broadcasters.
Obviously the DRM signal was suffering from sideband lobes falling into the DRM spectrum limiting the SNR because at the end when the modulation was already switched off the DRM SNR increased rapidly.


Voice audio snipped – first DRM, then switching to AM

Music audio snipped – first DRM, then switching to AM

The DRM audio was transmitted in AAC+ Mono with 18kBit/s. It gives a rather nice sound compared to other DRM broadcasts that can be received at the moment.