Gramophone
Gramophone Soundbox Recording |
My antique-redesign pet project.
Ever since I became fascinated with record players & antique phonographs in middle school, I've been developing my own, contemporary design for a mechanical-acoustic record player- a "modern gramophone".
Over the years, I've constructed various iterations of different gramophone components; mainly the horn, soundbox, tonearm, and body.
The horn is a faceted, mathematically-driven construction, and follows an exponential curve to optimize acoustic properties. The profiles of the horn facets needed to achieve this exponential curve were determined with a MATLAB script I found through this instructable. Initial prototypes of the horn were made with cardboard- the current iteration is a PETG construction, with facets cut with a scroll saw & solvent-welded together.
The soundbox, the component that translates record needle vibrations into acoustic energy, has undergone the most iterations. Initial designs, largely uninformed by research, consisted of a sewing needle projected through open-cell foam held in a narrow PVC pipe. The idea was to use the "crinkle" of the foam to amplify the needles vibrations, but was largely unsuccessful. I decided that more research was needed before I could design another iteration, and so I looked to antique gramophone patents from the early 1900's for inspiration. All of my subsequent designs have been directly inspired by the mechanisms outlined in these patents. Early prototypes used PVC housing, a 3D printed faceplate, and thin tinfoil for a diaphragm. These had limited success due to the fragility of the tinfoil, high friction in the pivots of the vibrating needle-arm, and non-optimal geometry. Attempts to use thicker tin sheets as a diaphragm in the same prototype found similar problems.
My latest soundbox iteration is entirely 3D printed- possibly the worlds first "3D Printed Soundbox". The design was based off of additional patent research and findings from earlier iterations, and every component was printed on a Form 2 SLA 3D printer. It is the most successful iteration thus far, and when used in conjunction with the horn, can amplify records to a listening volume.