Happy new year! Time to reveal what has been secretly developing in the lab throughout the past year: A stereophonic cutter head of an entirely unique design, invented by J. I. Agnew during his work with experimental transducers for measurement and testing purposes.
Continue reading “Lab Report: The Agnew Analog Stereophonic Cutter Head”
There is a long history of use of precious stones as industrial materials, from precision bearings to cutting tools, lapping compounds to grinding tools and several other specialised applications.
The recording of phonograph records is essentially a machining operation, performed by means of a machine tool called a disk recording lathe. A special cutting tool is used to cut a continuous spiral groove on the surface of a blank disk. This tool is called a disk recording stylus, or simply cutting stylus.
The big difference to other forms of machining is that there is sonic information stored as modulation of the cut groove, which can be reproduced on another special machine, often called turntable or record player, or disk reproduction system.
Many different stylus materials and geometries have been used through the years, along with different blank recording disk materials. The superiority of precious stones as cutting stylii was already evident from the early days of disk recording, so they are now the only type of stylus used for cutting masters for vinyl record manufacturing.
Continue reading “Precious Stones for Cutting Precious Records”
In the previous episode, we had a look at taper shank stylus adapters and saw a vintage magnetic monophonic cutter head fitted to the AM44 lathe. The two are not normally compatible. Neumann lathe suspensions do not have the same mount as the suspensions of Presto, Fairchild, RCA and other lathes of the monophonic era, which were originally designed to accept such cutter heads.
Continue reading “Lab Report: Cutter Head Mounting Adapters”