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ACOUSTICS IN MUSIC ARCHAEOLOGY their diameter is much smaller than would be appropri- ate for an externally affixed mouthpiece, a consideration not explored in the initial study. Due to the age and fragility of the Marsoulas conch, two resin replicas were commissioned, including the application of pigments to replicate those inside the archaeological shell. In September 2021, we compared the Marsoulas conch with its resin replicas in the Museum of Toulouse. The two resin replica horns produced tones with central frequencies comparable to those of the ancient seashell, verifying their suitability as experimental proxies. We then traveled to several caves in southern France for performance tests using one of the replica conch horns in associated archaeological settings, including a brief visit to the Marsoulas Cave where we made spatial acousti- cal impulse-response measurements and documented performance tests with the replica instrument. The long and narrow cave has been laser scanned and its extensive artworks investigated using customized image-processing techniques that allow production analyses and multime- dia reconstructions (Fritz and Tosello, 2010), as shown in Figure 2 (Fritz et al., 2016). The reunion of the Marsoulas conch, in the form of its functionally equal resin replica within its excavation context, the Marsoulas Cave, enabled observations about musical plausibilities in a site of the shell horn’s likely ancient sounding. Performance experiments can identify contextual sound effects, and they enable the description of site acoustical features that can be mea- sured and expressed according to standard procedures and metrics. Both outside and inside Marsoulas cave, the sounding tone of the replica conch horn was mea- sured from 258 to 260 Hz, within expected range of variation around the 256-Hz fundamental frequency documented in the shell horn’s acoustical study (Fritz et al., 2021). We first performed the replica horn on the edge of the ravine outside the opening of the cave into the adjacent valley below (Figure 4), from where we heard and recorded converging echoes that prolonged the instrument’s sounding tone for almost four seconds. In performance tests inside the cave, we documented frequencies produced using the downward pitch-bend- ing technique in which the player’s hand is partially inserted into the shell lip, or musical instrument bell, effectively lengthening its bore (Campbell et al., 2021). With the replica conch, the performer could “bend the tone down” to 234 Hz, extending the shell horn’s fre- quency range. Although to observers, sounds from the replica conch horn did seem to “fill the cave,” its perfor- mance did not notably excite spatial acoustical modes as we have observed in archaeoacoustics research with shell horns in architectural settings of similar dimen- sions, such as the stone galleries of Chavín de Huántar, Perú (see tinyurl.com/yckmef63) (Kolar, 2019). Figure 5. Experimental setup for acoustical impulse-response measurements in the central section of the Marsoulas Cave, adjacent to its iconic, red-dotted bison image (right). A portable omnidirectional loudspeaker and spatial audio recorder were used in this fieldwork conducted by Kolar, Nerness and Valentin in September 2021. Photo by Barbara Nerness. Figure 4. A music archaeology experimental study just outside the Marsoulas Cave using a 3D-printed and hand-painted replica of the Marsoulas conch. Performed here by auralization researcher Romain Michon. Photo by Barbara Nerness. 56 Acoustics Today • Summer 2022