A large EMG XA gramophone was bought to The Grimwade Centre for conservation treatment of the horn. Constructed of papier appliqué - a form of cardboard made by gluing strips of paper together, in this case, decorative printed paper, the coating on the surface had degraded.
The coating on the surface of the horn had degraded, with uneven cloudy, yellowed discolouration. This detracted visually from the horn. There were also small tears and losses around the outer rim of the horn, and some abrasions through the conical section.
The surface of the paper was cleaned with specialist erasers to reduce the dirt marks and general grime. Areas of lifting paper and loss were consolidated with dilute wheat starch paste. While aim of the conservation treatment was to restore the visual appearance of the horn, there was the added issue of preservation of the sound quality. Testing was undertaken to ensure that the treatment did not alter the acoustic qualities. Testing indicated that the best approach was to apply a size layer to the outer and inner surfaces, prior to a varnish layer, to ensure minimal penetration of the varnish into the paper, but allowing enough saturation of the degraded coating with an application of varnish to reduce the visual appearance of the degraded surface coating. Small losses were inpainted with Golden acrylic paints once the varnish had been applied.
Detail of degraded surface coating, before treatment.
Detail of degraded surface coating, after treatment.
Surface overall, after treatment.
Interior of horn, after treatment.