Diffusive front end in control room
Presented by Pierre THOMAS; FAR
Pierre-Yves WAUTHIER; Sound Engineer
The subjective test
Two basic rooms:
- A live room (RT60 around 500ms)
- A dead room with an almost flat frequency time curve (RT60 around 250ms)
Two free-standing active monitors, a desk with a console, a CD player, and selected audio samples were set equally in the rooms.
- Step 1: we listened to the audio samples in the live room
- Step 2: we surrounded the loudspeakers with Schroeder diffusers and listened again
- Step 3: we listened to the audio samples in the dead room
- Step 4: we surrounded the loudspeakers with Schroeder diffusers and listened again
- Step 5: we compared our impressions
Results
The perceived sound level in both the live and dead rooms was increased.
The acoustic shade of an item placed between the loudspeaker and the listener was drastically reduced inside the live room. In the dead room, the acoustic shade was reduced by an impressive amount, but not as much as in the live room.
The perception of the sound spectrum was improved in both rooms, yet was dependent on the room decay in the live room and really reliable in the dead room.
The perceived spectrum was equal to itself in a wide area. Actually, the sound field was really homogeneous in the whole room (except for boundaries) and reliable in a zone wider than the desk area.
The perception of reverberations in the playback signal was slightly improved in both rooms.
The left and/or right sounds remained localized to the left and/or right side even from a lateral listening position.
Extra-wideness and a rise of sibilance were heard in the live room.
The comb filtering effect of the desk’s first order reflection was much less perceptible than in the bare rooms.
The compact medium sized loudspeaker was turned toward a large sound source.
ETC response with free standing monitor in dead room with desk
Frequency response with free standing monitor in dead room with desk
ETC response with monitor surrounded with Schroeder diffusor in dead room with desk
Frequency response with monitor surrounded with Schroeder diffusor in dead room with desk
ETC response with monitor surrounded with Schroeder diffusor in dead room with desk
ETC response with free standing monitor in dead room with desk
Frequency response with monitor surrounded with Schroeder diffusor in dead room with desk
Frequency response with free standing monitor in dead room with desk
