This is the short version. Made in 1996 it talks about 2C3D rooms. These are certified rooms regarding their structure, room dimensions, interior acoustic treatments, electrical, HVAC, equipment, set-up, burn-in, calibration and testing of acoustic room specifications. This certification criteria was headed up by Norman Varney and was in cooperation with; MIT, Spectral, ASC Tube Traps and Avalon Acoustics. There was also a 5C3D certification program.
The 2C3D room recorded for this CD has a room volume of 3,042 cu. Ft., the small room is 1,152 cu. Ft. and the large room is 6,132 cu. Ft.
Note: Human perception is easily fooled, when doing A/B comparisons, into believing that a louder signal is better. The small room is louder than the 2C3D room because the boundaries are closer to the speakers and listening position. It also sounds brighter for the same reason, and the fact that there are no added acoustical treatments. The larger room sounds louder and brighter because of the reverberation reinforcement.
The samples of music were recorded at 90dBA reference acoustic levels, with the exact same playback system. The rooms are the only difference. The first of each sample was recorded in a 2C3D treated environment. The second was recorded in a smaller, untreated environment, revealing bass region problems in particular. The last was recorded in a larger, untreated environment, revealing excessive reverberation in particular. With headphones you will not perceive the typical 3 dimensional soundstage, however, it is easy to notice the colorations in timber and articulation, ambiance, noise floor, etc. Listen closely for changes in emotional impact as well. These are real. Because of the distortions there are changes in attack and decay, pitch, tempo and loudness.
Chain for playback system
• Sony CDP-XA7ES
Chain for recording system
• B&K 4006 microphones with nose cone adapters and B&K stereo bar
Chain for editing system
• Panasonic 3800 DAT
Produced by Music Interface Technologies
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