AES64
Libraries and archives around the world have collections of many thousands of coarse-groove mechanical audio recordings many of which are 78s or 78 rpm discs. This is a substantial recorded heritage of mankind's music and spoken word. These mechanical recordings won't be available indefinitely since the plastics used in their manufacture are deteriorating slowly but steadily. Conservation programs have been underway by a number of organizations. Decreasing costs of digital storage media now make it possible to consider all mechanical audio recordings for transfer to the digital domain. Thus a widespread need was recognized by the Audio Engineering Society(AES) to provide a calibration tool for standard transfer of mechanical coarse-groove audio recordings from the analog to the digital domain. [1]
The AES Coarse-groove calibration disc (AES-S001-064)is a boxed set of two indentical discs, one for routine use, one for master reference. The intent is to characterize the reproduction chain for the mass transfer of coarse-groove records to digital media, much like using a photographic calibration reference in image work. [2]
Side A:
- Gliding tone, 20 Hz to 20 kHz
- Speed: 77.92 rpm
- Lateral (mono) coarse groove
- Time constants: 3180/450/0 ms
- Separate outer & inner bands:
- 1 kHz trigger tone
- Gliding tone, 20 Hz to 20 kHz
- 1 kHz reference level*
- *20 mm Light Band Width (LBW);
- approx 8 cm/s peak-to-peak, 5.7 cm/s rms
Side B:
- Single tomes, 18kHz to 30 Hz
- Speed: 77.92 rpm
- Lateral (mono) coarse groove
- Time constants: 3180/450/50 ms
(Pressed under license from EMI Records Ltd.)
Notes
- ^ Audio Engineering Society Standards Committee, AES 78 rpm Calibration Disc Set (last updated 2007-07-20).
- ^ http://www.aes.org/standards/b_data/x064-rationale.cfm