Magnetic Reference Laboratory
Magnetic Reference Laboratory (MRL) is an American company founded in 1972. They make and sell Calibration Tapes[1] for analog audio magnetic tape reproducers in the Open Reel format.
Origins
In 1972 John G. McKnight was laid off from Ampex, as was Tony Bardakos, who was making the calibration tapes for Ampex at the time. Along with Ed Seaman (also an ex-Ampex employee), McKnight and Bardakos decided to start their own calibration tape business, and thus Magnetic Reference Lab (MRL) was born in 1972.[2]
Products
MRL makes a wide variety of calibration tapes (a tape that "contains test signals used to calibrate a tape reproducer so that it will conform to the accepted standards"[1]) that are sold world-wide. Examples of available test signals include:
- Multifrequency (general purpose, for setting reproducer gain, azimuth, and frequency response from 32 Hz to 20 kHz)
- Polarity Calibration
- Special signals for Sound Technology or for Audio Precision measurement systems
- Fast Swept-frequency for use with an oscilloscope
- Slow Swept-frequency for use with a plotter
- Single frequencies
- Broadband Pink Noise
- Broadband White noise
- Chromatic Sweep for use on a reproducer's VU meter
Customers
MRL's calibration tapes are used by anyone who wants to have their analog audio magnetic tape reproducer properly calibrated, including:
- Professional music studios
- Radio stations
- Audio departments at major universities
- Theme parks
References
- 1 2 What is a Calibration Tape
- ↑ Behind The Gear: Jay McKnight of Magnetic Reference Laboratory", by Alex Kostelnik, from Tape Op, Nr 52 (2006 Mar/Apr)