ABSTRACT
During the 78-rpm era, phonograph needles were sold in tin boxes, often bearing colorful designs; they have become collectors’ items. Many of the needles were made by record manufacturers, and carry the same logo as the disc labels of those companies. For example, Nipper appears on HMV needle tins, and the two-note Columbia trademark on its tins. Not all needles were sold in tins; there were also various kinds of paper boxes and even aluminum boxes. [Lambert 1985 gives numerous illustrations.]
The inversion and return of a portion of an amplifier’s output to its input. It is used intentionally to reduce distortion and to provide more predictable amplification and response. Since negative feedback also reduces gain, the amplifier must have a greater open-loop gain to compensate for this factor. But the considerable improvement in many other characteristics often outweighs the reduction in gain.
